Exemple #1
0
class EntityBrowser(SupportsManageMixin, QDialog, Ui_EntityBrowser):
    """
    Dialog for browsing entity records in a table view.
    """

    # Custom signal that is raised when the dialog
    # is in SELECT state. It contains
    # the record id of the selected row.

    recordSelected = pyqtSignal(int)

    def __init__(self,
                 entity,
                 parent=None,
                 state=MANAGE,
                 load_records=True,
                 plugin=None):
        QDialog.__init__(self, parent)
        self.setupUi(self)

        # Add maximize buttons
        self.setWindowFlags(self.windowFlags() | Qt.WindowSystemMenuHint
                            | Qt.WindowMaximizeButtonHint)

        SupportsManageMixin.__init__(self, state)
        # Init document viewer setup
        self._view_docs_act = None
        viewer_title = QApplication.translate('EntityBrowser',
                                              'Document Viewer')
        self.doc_viewer_title = u'{0} {1}'.format(entity.ui_display(),
                                                  viewer_title)
        self._doc_viewer = _EntityDocumentViewerHandler(
            self.doc_viewer_title, self)
        self.load_records = load_records
        #Initialize toolbar
        self.plugin = plugin
        self.tbActions = QToolBar()
        self.tbActions.setObjectName('eb_actions_toolbar')
        self.tbActions.setIconSize(QSize(16, 16))
        self.tbActions.setToolButtonStyle(Qt.ToolButtonIconOnly)
        self.vlActions.addWidget(self.tbActions)

        self._entity = entity
        self._dbmodel = entity_model(entity)
        self._state = state
        self._tableModel = None
        self._parent = parent
        self._data_initialized = False
        self._notifBar = NotificationBar(self.vlNotification)
        self._headers = []
        self._entity_attrs = []
        self._cell_formatters = {}
        self.filtered_records = []
        self._searchable_columns = OrderedDict()
        self._show_docs_col = False
        self.child_model = OrderedDict()
        #ID of a record to select once records have been added to the table
        self._select_item = None
        self.current_records = 0

        self.record_limit = get_entity_browser_record_limit()

        #Enable viewing of supporting documents
        if self.can_view_supporting_documents:
            self._add_view_supporting_docs_btn()

        self._add_advanced_search_btn()
        #Connect signals
        self.buttonBox.accepted.connect(self.onAccept)
        self.tbEntity.doubleClicked[QModelIndex].connect(
            self.onDoubleClickView)

    def children_entities(self):
        """
        :return: Returns a list of children entities
        that refer to the main entity as the parent.
        :rtype: list
        """
        return [
            ch for ch in self._entity.children()
            if ch.TYPE_INFO == Entity.TYPE_INFO
        ]

    @property
    def entity(self):
        """
        :return: Returns the Entity object used in this browser.
        :rtype: Entity
        """
        return self._entity

    @property
    def can_view_supporting_documents(self):
        """
        :return: True if the browser supports the viewing of supporting
        documents.
        :rtype: bool
        """
        test_ent_obj = self._dbmodel()

        if self._entity.supports_documents \
                and hasattr(test_ent_obj, 'documents'):
            return True

        return False

    def _add_view_supporting_docs_btn(self):
        #Add button for viewing supporting documents if supported
        view_docs_str = QApplication.translate('EntityBrowser',
                                               'View Documents')
        self._view_docs_act = QAction(
            QIcon(':/plugins/stdm/images/icons/document.png'), view_docs_str,
            self)

        #Connect signal for showing document viewer
        self._view_docs_act.triggered.connect(self.on_load_document_viewer)

        self.tbActions.addAction(self._view_docs_act)

    def _add_advanced_search_btn(self):
        #Add button for viewing supporting documents if supported
        search_str = QApplication.translate('EntityBrowser', 'Advanced Search')
        self._search_act = QAction(
            QIcon(':/plugins/stdm/images/icons/advanced_search.png'),
            search_str, self)

        #Connect signal for showing document viewer
        self._search_act.triggered.connect(self.on_advanced_search)

        self.tbActions.addAction(self._search_act)

    def dateFormatter(self):
        """
        Function for formatting date values
        """
        return self._dateFormatter

    def setDateFormatter(self, formatter):
        """
        Sets the function for formatting date values. Overrides the default function.
        """
        self._dateFormatter = formatter

    def state(self):
        '''
        Returns the current state that the dialog has been configured in.
        '''
        return self._state

    def setState(self, state):
        '''
        Set the state of the dialog.
        '''
        self._state = state

    def set_selection_record_id(self, id):
        """
        Set the ID of a record to be selected only once all records have been
        added to the table view.
        :param id: Record id to be selected.
        :type id: int
        """
        self._select_item = id

    def title(self):
        '''
        Set the title of the entity browser dialog.
        Protected method to be overridden by subclasses.
        '''
        records = QApplication.translate('EntityBrowser', 'Records')
        if self._entity.label != '':
            title = self._entity.label
        else:
            title = self._entity.ui_display()

        return u'{} {}'.format(title, records)

    def setCellFormatters(self, formattermapping):
        '''
        Dictionary of attribute mappings and corresponding functions for
        formatting the attribute value to the display value.
        '''
        self._cell_formatters = formattermapping

    def addCellFormatter(self, attributeName, formatterFunc):
        '''
        Add a new cell formatter configuration to the collection
        '''
        self._cell_formatters[attributeName] = formatterFunc

    def showEvent(self, showEvent):
        '''
        Override event for loading the database records once the dialog is visible.
        This is for improved user experience i.e. to prevent the dialog from taking
        long to load.
        '''
        self.setWindowTitle(unicode(self.title()))

        if self._data_initialized:
            return
        try:
            if not self._dbmodel is None:
                # cProfile.runctx('self._initializeData()', globals(), locals())
                self._initializeData()

        except Exception as ex:
            pass

        self._data_initialized = True

    def hideEvent(self, hideEvent):
        '''
        Override event which just sets a flag to indicate that the data records have already been
        initialized.
        '''
        pass

    def clear_selection(self):
        """
        Deselects all selected items in the table view.
        """
        self.tbEntity.clearSelection()

    def clear_notifications(self):
        """
        Clears all notifications messages in the dialog.
        """
        self._notifBar.clear()

    def recomputeRecordCount(self, init_data=False):
        '''
        Get the number of records in the specified table and updates the window title.
        '''
        entity = self._dbmodel()

        # Get number of records
        numRecords = entity.queryObject().count()
        if init_data:
            if self.current_records < 1:
                if numRecords > self.record_limit:
                    self.current_records = self.record_limit
                else:
                    self.current_records = numRecords

        rowStr = QApplication.translate('EntityBrowser', 'row') \
            if numRecords == 1 \
            else QApplication.translate('EntityBrowser', 'rows')
        showing = QApplication.translate('EntityBrowser', 'Showing')
        windowTitle = u"{0} - {1} {2} of {3} {4}".format(
            self.title(), showing, self.current_records, numRecords, rowStr)

        self.setWindowTitle(windowTitle)

        return numRecords

    def _init_entity_columns(self):
        """
        Asserts if the entity columns actually do exist in the database. The
        method also initializes the table headers, entity column and cell
        formatters.
        """
        self._headers[:] = []
        table_name = self._entity.name
        columns = table_column_names(table_name)
        missing_columns = []

        header_idx = 0

        #Iterate entity column and assert if they exist

        for c in self._entity.columns.values():

            # Exclude geometry columns
            if isinstance(c, GeometryColumn):
                continue

            #Do not include virtual columns in list of missing columns
            if not c.name in columns and not isinstance(c, VirtualColumn):
                missing_columns.append(c.name)

            else:
                header = c.ui_display()
                self._headers.append(header)

                col_name = c.name
                '''
                If it is a virtual column then use column name as the header
                but fully qualified column name (created by SQLAlchemy
                relationship) as the entity attribute name.
                '''

                if isinstance(c, MultipleSelectColumn):
                    col_name = c.model_attribute_name

                self._entity_attrs.append(col_name)

                # Get widget factory so that we can use the value formatter
                w_factory = ColumnWidgetRegistry.factory(c.TYPE_INFO)
                if not w_factory is None:
                    formatter = w_factory(c)
                    self._cell_formatters[col_name] = formatter

                #Set searchable columns
                if c.searchable:
                    self._searchable_columns[c.ui_display()] = {
                        'name': c.name,
                        'header_index': header_idx
                    }

                header_idx += 1

        if len(missing_columns) > 0:
            msg = QApplication.translate(
                'EntityBrowser',
                u'The following columns have been defined in the '
                u'configuration but are missing in corresponding '
                u'database table, please re-run the configuration wizard '
                u'to create them.\n{0}'.format('\n'.join(missing_columns)))

            QMessageBox.warning(
                self, QApplication.translate('EntityBrowser',
                                             'Entity Browser'), msg)

    def _select_record(self, id):
        #Selects record with the given ID.
        if id is None:
            return

        m = self.tbEntity.model()
        s = self.tbEntity.selectionModel()

        start_idx = m.index(0, 0)
        idxs = m.match(start_idx, Qt.DisplayRole, id, 1, Qt.MatchExactly)

        if len(idxs) > 0:
            sel_idx = idxs[0]
            #Select item
            s.select(
                sel_idx,
                QItemSelectionModel.ClearAndSelect | QItemSelectionModel.Rows)

    def on_advanced_search(self):
        search = AdvancedSearch(self._entity, parent=self)
        search.show()

    def on_load_document_viewer(self):
        #Slot raised to show the document viewer for the selected entity
        sel_rec_ids = self._selected_record_ids()

        if len(sel_rec_ids) == 0:
            return

        #Get document objects
        ent_obj = self._dbmodel()

        for sel_id in sel_rec_ids:
            er = ent_obj.queryObject().filter(
                self._dbmodel.id == sel_id).first()
            if not er is None:
                docs = er.documents

                #Notify there are no documents for the selected doc
                if len(docs) == 0:
                    msg = QApplication.translate(
                        'EntityBrowser',
                        'There are no supporting documents for the selected record.'
                    )

                    QMessageBox.warning(self, self.doc_viewer_title, msg)

                    continue

                self._doc_viewer.load(docs)

    def _initializeData(self, filtered_records=None):
        '''
        Set table model and load data into it.
        '''
        if self._dbmodel is None:
            msg = QApplication.translate(
                'EntityBrowser',
                'The data model for the entity could not be loaded, \n'
                'please contact your database administrator.')
            QMessageBox.critical(
                self, QApplication.translate('EntityBrowser',
                                             'Entity Browser'), msg)

        else:
            self._init_entity_columns()
            # Load entity data. There might be a better way in future in order
            # to ensure that there is a balance between user data discovery
            # experience and performance.
            if filtered_records is not None:
                self.current_records = filtered_records.rowcount

            numRecords = self.recomputeRecordCount(init_data=True)

            # Load progress dialog
            progressLabel = QApplication.translate("EntityBrowser",
                                                   "Fetching Records...")
            progressDialog = QProgressDialog(progressLabel, None, 0,
                                             numRecords, self)

            QApplication.processEvents()
            progressDialog.show()
            progressDialog.setValue(0)

            #Add records to nested list for enumeration in table model
            load_data = True
            if self.plugin is not None:
                if self._entity.name in self.plugin.entity_table_model.keys():
                    if filtered_records is None:
                        self._tableModel = self.plugin.entity_table_model[
                            self._entity.name]
                        #load_data = False
                    #else:
                    #load_data = True

            if isinstance(self._parent, EntityEditorDialog):
                load_data = True

            if load_data:
                # Only one filter is possible.
                if filtered_records is not None:
                    entity_records = filtered_records
                else:
                    entity_records = fetch_from_table(self._entity.name,
                                                      limit=self.record_limit)

            # if self._tableModel is None:
                entity_records_collection = []
                for i, er in enumerate(entity_records):
                    if i == self.record_limit:
                        break
                    QApplication.processEvents()
                    entity_row_info = []
                    progressDialog.setValue(i)
                    try:
                        # for attr, attr_val in er.items():
                        # print e
                        for attr in self._entity_attrs:
                            # attr_val = getattr(er, attr)
                            attr_val = er[attr]

                            # Check if there are display formatters and apply if
                            # one exists for the given attribute.
                            if attr_val is not None:  # No need of formatter for None value
                                if attr in self._cell_formatters:
                                    formatter = self._cell_formatters[attr]
                                    attr_val = formatter.format_column_value(
                                        attr_val)
                            entity_row_info.append(attr_val)
                    except Exception as ex:
                        QMessageBox.critical(
                            self,
                            QApplication.translate('EntityBrowser',
                                                   'Loading Records'),
                            unicode(ex.message))
                        return

                    entity_records_collection.append(entity_row_info)

                self._tableModel = BaseSTDMTableModel(
                    entity_records_collection, self._headers, self)
                if self.plugin is not None:
                    self.plugin.entity_table_model[self._entity.name] = \
                            self._tableModel
            # Add filter columns
            for header, info in self._searchable_columns.iteritems():
                column_name, index = info['name'], info['header_index']
                if column_name != 'id':
                    self.cboFilterColumn.addItem(header, info)

            #Use sortfilter proxy model for the view
            self._proxyModel = VerticalHeaderSortFilterProxyModel()
            self._proxyModel.setDynamicSortFilter(True)
            self._proxyModel.setSourceModel(self._tableModel)
            self._proxyModel.setSortCaseSensitivity(Qt.CaseInsensitive)

            #USe first column in the combo for filtering
            if self.cboFilterColumn.count() > 0:
                self.set_proxy_model_filter_column(0)

            self.tbEntity.setModel(self._proxyModel)
            if numRecords < self.record_limit:
                self.tbEntity.setSortingEnabled(True)
                self.tbEntity.sortByColumn(1, Qt.AscendingOrder)

            #First (ID) column will always be hidden
            self.tbEntity.hideColumn(0)

            self.tbEntity.horizontalHeader().setResizeMode(
                QHeaderView.Interactive)

            self.tbEntity.resizeColumnsToContents()

            #Connect signals
            self.connect(self.cboFilterColumn,
                         SIGNAL('currentIndexChanged (int)'),
                         self.onFilterColumnChanged)
            self.connect(self.txtFilterPattern,
                         SIGNAL('textChanged(const QString&)'),
                         self.onFilterRegExpChanged)

            #Select record with the given ID if specified
            if not self._select_item is None:
                self._select_record(self._select_item)

            if numRecords > 0:
                # Set maximum value of the progress dialog
                progressDialog.setValue(numRecords)
            else:
                progressDialog.hide()

    def _header_index_from_filter_combo_index(self, idx):
        col_info = self.cboFilterColumn.itemData(idx)

        return col_info['name'], col_info['header_index']

    def set_proxy_model_filter_column(self, index):
        #Set the filter column for the proxy model using the combo index
        name, header_idx = self._header_index_from_filter_combo_index(index)
        self._proxyModel.setFilterKeyColumn(header_idx)

    def onFilterColumnChanged(self, index):
        '''
        Set the filter column for the proxy model.
        '''
        self.set_proxy_model_filter_column(index)

    def _onFilterRegExpChanged(self, text):
        cProfile.runctx('self._onFilterRegExpChanged(text)', globals(),
                        locals())

    def onFilterRegExpChanged(self, text):
        '''
        Slot raised whenever the filter text changes.
        '''
        regExp = QRegExp(text, Qt.CaseInsensitive, QRegExp.FixedString)
        self._proxyModel.setFilterRegExp(regExp)

    def onDoubleClickView(self, modelindex):
        '''
        Slot raised upon double clicking the table view.
        To be implemented by subclasses.
        '''
        pass

    def _selected_record_ids(self):
        '''
        Get the IDs of the selected row in the table view.
        '''
        self._notifBar.clear()

        selected_ids = []
        sel_row_indices = self.tbEntity.selectionModel().selectedRows(0)

        if len(sel_row_indices) == 0:
            msg = QApplication.translate(
                "EntityBrowser", "Please select a record from the table.")

            self._notifBar.insertWarningNotification(msg)

            return selected_ids

        for proxyRowIndex in sel_row_indices:
            #Get the index of the source or else the row items will have unpredictable behavior
            row_index = self._proxyModel.mapToSource(proxyRowIndex)
            entity_id = row_index.data(Qt.DisplayRole)
            selected_ids.append(entity_id)

        return selected_ids

    def onAccept(self):
        '''
        Slot raised when user clicks to accept the dialog. The resulting action will be dependent
        on the state that the browser is currently configured in.
        '''
        selIDs = self._selected_record_ids()
        if len(selIDs) == 0:
            return

        if self._mode == SELECT:
            #Get all selected records
            for sel_id in selIDs:
                self.recordSelected.emit(sel_id)

            rec_selected = QApplication.translate('EntityBrowser',
                                                  'record(s) selected')

            msg = u'{0:d} {1}.'.format(len(selIDs), rec_selected)
            self._notifBar.insertInformationNotification(msg)

    def addModelToView(self, model_obj):
        '''
        Convenience method for adding model info into the view.
        '''
        insertPosition = self._tableModel.rowCount()
        self._tableModel.insertRows(insertPosition, 1)

        for i, attr in enumerate(self._entity_attrs):

            prop_idx = self._tableModel.index(insertPosition, i)
            attr_val = getattr(model_obj, attr)
            '''
            Check if there are display formatters and apply if one exists
            for the given attribute.
            '''
            if attr in self._cell_formatters:
                formatter = self._cell_formatters[attr]
                attr_val = formatter.format_column_value(attr_val)

            self._tableModel.setData(prop_idx, attr_val)
        return insertPosition

    def _model_from_id(self, record_id, row_number):
        '''
        Convenience method that returns the model object based on its ID.
        '''
        dbHandler = self._dbmodel()
        modelObj = dbHandler.queryObject().filter(
            self._dbmodel.id == record_id).first()
        if modelObj is None:
            modelObj = self.child_model[row_number + 1, self.entity]

        return modelObj if not modelObj is None else None
Exemple #2
0
class ForeignKeyMapper(QWidget):
    """
    Widget for selecting database records through an entity browser or
    using an ExpressionBuilder for filtering records.
    """
    #Custom signals
    beforeEntityAdded = pyqtSignal("PyQt_PyObject")
    afterEntityAdded = pyqtSignal("PyQt_PyObject", int)
    entityRemoved = pyqtSignal("PyQt_PyObject")
    deletedRows = pyqtSignal(list)

    def __init__(self, entity, parent=None, notification_bar=None,
                 enable_list=True, can_filter=False, plugin=None):

        QWidget.__init__(self, parent)
        self.current_profile = current_profile()

        self._tbFKEntity = QTableView(self)
        self._tbFKEntity.setEditTriggers(QAbstractItemView.NoEditTriggers)
        self._tbFKEntity.setAlternatingRowColors(True)
        self._tbFKEntity.setSelectionBehavior(QAbstractItemView.SelectRows)
        self.plugin = plugin
        self._add_entity_btn = QToolButton(self)
        self._add_entity_btn.setToolTip(
            QApplication.translate("ForeignKeyMapper","Add"))
        self._add_entity_btn.setIcon(
            QIcon(":/plugins/stdm/images/icons/add.png"))
        self._add_entity_btn.clicked.connect(self.onAddEntity)

        self._edit_entity_btn = QToolButton(self)
        self._edit_entity_btn.setVisible(False)
        self._edit_entity_btn.setToolTip(
            QApplication.translate("ForeignKeyMapper","Edit"))
        self._edit_entity_btn.setIcon(
            QIcon(":/plugins/stdm/images/icons/edit.png"))

        self._filter_entity_btn = QToolButton(self)
        self._filter_entity_btn.setVisible(False)
        self._filter_entity_btn.setToolTip(
            QApplication.translate("ForeignKeyMapper","Select by expression"))
        self._filter_entity_btn.setIcon(
            QIcon(":/plugins/stdm/images/icons/filter.png"))
        self._filter_entity_btn.clicked.connect(self.onFilterEntity)

        self._delete_entity_btn = QToolButton(self)
        self._delete_entity_btn.setToolTip(
            QApplication.translate("ForeignKeyMapper","Remove"))
        self._delete_entity_btn.setIcon(
            QIcon(":/plugins/stdm/images/icons/remove.png"))
        self._delete_entity_btn.clicked.connect(self.onRemoveEntity)

        layout = QVBoxLayout(self)
        layout.setSpacing(4)
        layout.setMargin(5)

        self.grid_layout = QGridLayout(self)
        self.grid_layout.setHorizontalSpacing(5)
        self.grid_layout.addWidget(self._add_entity_btn, 0, 0, 1, 1)
        self.grid_layout.addWidget(self._filter_entity_btn, 0, 1, 1, 1)
        self.grid_layout.addWidget(self._edit_entity_btn, 0, 2, 1, 1)
        self.grid_layout.addWidget(self._delete_entity_btn, 0, 3, 1, 1)
        self.grid_layout.setColumnStretch(4, 5)

        layout.addLayout(self.grid_layout)
        layout.addWidget(self._tbFKEntity)
        self.social_tenure = self.current_profile.social_tenure

        self._tableModel = None
        self._notifBar = notification_bar
        self._headers = []
        self._entity_attrs = []
        self._cell_formatters = {}
        self._searchable_columns = OrderedDict()
        self._supportsLists = enable_list
        self._deleteOnRemove = False
        self._uniqueValueColIndices = OrderedDict()
        self.global_id = None
        self._deferred_objects = {}
        self._use_expression_builder = can_filter

        if self._use_expression_builder:
            self._filter_entity_btn.setVisible(True)
            self._edit_entity_btn.setVisible(False)
        self.set_entity(entity)

    def set_entity(self, entity):
        """
        Sets new entity and updates the ForeignKeyMapper with a new
        :param entity: The entity of the ForeignKeyMapper
        :type entity:Object
        """
        from stdm.ui.entity_browser import EntityBrowser

        self._entity = entity

        self._dbmodel = entity_model(entity)
        self._init_fk_columns()
        self._entitySelector = EntityBrowser(
            self._entity,
            parent=self,
            state=SELECT,
            plugin=self.plugin
        )

        # Connect signals
        self._entitySelector.recordSelected.connect(
            self._onRecordSelectedEntityBrowser
        )

    def _init_fk_columns(self):
        """
        Asserts if the entity columns actually do exist in the database. The
        method also initializes the table headers, entity column and cell
        formatters.
        """
        self._headers[:] = []
        self._entity_attrs[:] = []
        if self._dbmodel is None:
            msg = QApplication.translate(
                'ForeignKeyMapper', 'The data model for '
                                  'the entity could '
                                  'not be loaded, '
                                  'please contact '
                                  'your database '
                                  'administrator.'
            )
            QMessageBox.critical(
                self,
                QApplication.translate(
                    'EntityBrowser',
                    'Entity Browser'
                ),
                msg
            )

            return

        table_name = self._entity.name
        columns = table_column_names(table_name)
        missing_columns = []

        header_idx = 0

        #Iterate entity column and assert if they exist
        for c in self._entity.columns.values():
            #Do not include virtual columns in list of missing columns
            if not c.name in columns and not isinstance(c, VirtualColumn):
                missing_columns.append(c.name)

            else:
                header = c.header()
                self._headers.append(header)
                '''
                If it is a virtual column then use column name as the header
                but fully qualified column name (created by SQLAlchemy
                relationship) as the entity attribute name.
                '''
                col_name = c.name

                if isinstance(c, MultipleSelectColumn):
                    col_name = c.model_attribute_name

                self._entity_attrs.append(col_name)

                #Get widget factory so that we can use the value formatter
                w_factory = ColumnWidgetRegistry.factory(c.TYPE_INFO)
                if not w_factory is None:
                    try:
                        formatter = w_factory(c)
                        self._cell_formatters[col_name] = formatter
                    except WidgetException as we:
                        msg = QApplication.translate(
                            'ForeignKeyMapper',
                            'Error in creating column:'
                        )
                        msg = '{0} {1}:{2}\n{3}'.format(
                            msg, self._entity.name, c.name, unicode(we)
                        )
                        QMessageBox.critical(
                            self,
                            QApplication.translate(
                                'ForeignKeyMapper',
                                'Widget Creation Error'
                            ),
                            msg
                        )

                #Set searchable columns
                if c.searchable:
                    self._searchable_columns[header] = {
                        'name': c.name,
                        'header_index': header_idx
                    }

                header_idx += 1

        if len(missing_columns) > 0:
            msg = QApplication.translate(
                'ForeignKeyMapper',
                u'The following columns have been defined in the '
                u'configuration but are missing in corresponding '
                u'database table, please re-run the configuration wizard '
                u'to create them.\n{0}'.format(
                    '\n'.join(missing_columns)
                )
            )

            QMessageBox.warning(
                self,
                QApplication.translate('ForeignKeyMapper','Entity Browser'),
                msg
            )

        self._tableModel = BaseSTDMTableModel([], self._headers, self)
        self._tbFKEntity.setModel(self._tableModel)
        self._tbFKEntity.resizeColumnsToContents()
        #First (id) column will always be hidden
        self._tbFKEntity.hideColumn(0)

        self._tbFKEntity.horizontalHeader().setResizeMode(
            QHeaderView.Interactive
        )
        self._tbFKEntity.verticalHeader().setVisible(True)


    def databaseModel(self):
        '''
        Returns the database model that represents the foreign key entity.
        '''
        return self._dbmodel
    
    def setDatabaseModel(self,model):
        '''
        Set the database model that represents the foreign key entity.
        Model has to be a callable.
        '''
        self._dbmodel = model
        
    def cellFormatters(self):
        """
        Returns a dictionary of cell formatters used by the foreign key mapper.
        """
        return self._cell_formatters

    def cell_formatter(self, column):
        """
        :param column: Column name:
        :type column: str
        :return: Returns the corresponding formatter object based on the
        column name. None will be returned if there is no corresponding
        object.
        :rtype: object
        """
        return self._cell_formatters.get(column, None)
    
    def entitySelector(self):
        '''
        Returns the dialog for selecting the entity objects.
        '''
        return self._entitySelector
        
    def supportList(self):
        '''
        Returns whether the mapper supports only one item or multiple entities.
        Default is 'True'.
        '''
        return self._supportsLists
    
    def setSupportsList(self,supportsList):
        '''
        Sets whether the mapper supports only one item or multiple entities i.e.
        one-to-one (False) and one-to-many mapping (True).
        '''
        self._supportsLists = supportsList
        
    def setNotificationBar(self,notificationBar):
        '''
        Set the notification bar for displaying user messages.
        '''
        self._notifBar = notificationBar
        
    def viewModel(self):
        '''
        Return the view model used by the table view.
        '''
        return self._tableModel

    def set_expression_builder(self, state):
        """
        Set the mapper to use QGIS expression builder as the entity selector.
        """
        self._use_expression_builder = state

    def expression_builder_enabled(self):
        """
        Returns whether the mapper has been configured to use the expression builder
        """
        return self._use_expression_builder
    
    def deleteOnRemove(self):
        '''
        Returns the state whether a record should be deleted from the database when it 
        is removed from the list.
        '''
        return self._deleteOnRemove
    
    def setDeleteonRemove(self,delete):
        '''
        Set whether whether a record should be deleted from the database when it 
        is removed from the list.
        '''
        self._deleteOnRemove = delete
        
    def addUniqueColumnName(self,colName,replace = True):
        '''
        Set the name of the column whose values are to be unique.
        If 'replace' is True then the existing row will be replaced
        with one with the new value; else, the new row will not be added to the list.
        '''
        headers = self._dbmodel.displayMapping().values()
        colIndex = getIndex(headers,colName)
        
        if colIndex != -1:
            self.addUniqueColumnIndex(colIndex, replace)
        
    def addUniqueColumnIndex(self,colIndex,replace = True):
        '''
        Set the index of the column whose values are to be unique. The column indices are
        zero-based.
        If 'replace' is True then the existing row will be replaced with the
        new value; else, the new row will not be added to the list.
        For multiple replace rules defined, then the first one added to the collection is the
        one that will be applied.
        '''
        self._uniqueValueColIndices[colIndex] = replace

    def onFilterEntity(self):
        """
        Slot raised to load the expression builder dialog.
        """
        vl, msg = self.vector_layer()

        if vl is None:
            msg = msg + "\n" + QApplication.translate("ForeignKeyMapper",
                            "The expression builder cannot be used at this moment.")
            QMessageBox.critical(self, QApplication.translate("ForeignKeyMapper",
                                            "Expression Builder"), msg)

            return

        context = self._entity.short_name

        filter_dlg = ForeignKeyMapperExpressionDialog(vl, self, context=context)
        filter_dlg.setWindowTitle(QApplication.translate("ForeignKeyMapper",
                                                    "Filter By Expression"))
        filter_dlg.recordSelected[int].connect(self._onRecordSelectedEntityBrowser)

        res = filter_dlg.exec_()
    
    def _removeRow(self,rowNumber):
        '''
        Remove the row at the given index.
        '''
        self._tableModel.removeRows(rowNumber, 1)
        
    def onRemoveEntity(self):
        '''
        Slot raised on clicking to remove the selected entity.
        '''
        selectedRowIndices = self._tbFKEntity.selectionModel().selectedRows(0)

        deleted_rows = []
        if len(selectedRowIndices) == 0:
            msg = QApplication.translate(
                "ForeignKeyMapper",
                "Please select the record to be removed."
            )
            self._notifBar.clear()
            self._notifBar.insertWarningNotification(msg)
            return
            
        for selectedRowIndex in selectedRowIndices:
            #Delete record from database if flag has been set to True
            recId= selectedRowIndex.data()
            
            dbHandler = self._dbmodel()
            delRec = dbHandler.queryObject().filter(self._dbmodel.id == recId).first()
            
            if not delRec is None:
                self.entityRemoved.emit(delRec)
                
                if self._deleteOnRemove:
                    delRec.delete()
            
            self._removeRow(selectedRowIndex.row())

            deleted_rows.append(selectedRowIndex.row())

        self.deletedRows.emit(deleted_rows)
            
    def _recordIds(self):
        '''
        Returns the primary keys of the records in the table.
        '''
        recordIds = []

        if self._tableModel:
            rowCount = self._tableModel.rowCount()
            
            for r in range(rowCount):
                #Get ID value
                modelIndex = self._tableModel.index(r, 0)
                modelId = modelIndex.data()
                recordIds.append(modelId)
                    
        return recordIds
            
    def entities(self):
        '''
        Returns the model instance(s) depending on the configuration specified by the user.
        '''
        recIds = self._recordIds()
                
        modelInstances = self._modelInstanceFromIds(recIds)
        
        if len(modelInstances) == 0:
            if self._supportsLists:
                return []

            else:
                return None

        else:
            if self._supportsLists:
                return modelInstances

            else:
                return modelInstances[0]
            
    def setEntities(self, entities):
        '''
        Insert entities into the table.
        '''
        if isinstance(entities, list):
            for entity in entities:
                self._insertModelToView(entity)
                
        else:
            self._insertModelToView(entities)
            
    def searchModel(self, columnIndex, columnValue):
        '''
        Searches for 'columnValue' in the column whose index is specified by 'columnIndex' in all 
        rows contained in the model.
        '''
        if isinstance (columnValue, QVariant):
            columnValue = unicode(columnValue.toString())

        if not isinstance(columnValue, str) or \
                not isinstance(columnValue, unicode):
            columnValue = unicode(columnValue)

        columnValue = columnValue.strip()

        proxy = QSortFilterProxyModel(self)
        proxy.setSourceModel(self._tableModel)
        proxy.setFilterKeyColumn(columnIndex)
        proxy.setFilterFixedString(columnValue)
        #Will return model index containing the primary key.
        matchingIndex = proxy.mapToSource(proxy.index(0,0))

        return matchingIndex
    
    def _modelInstanceFromIds(self,ids):
        '''
        Returns the model instance based the value of its primary key.
        '''
        dbHandler = self._dbmodel()
        
        modelInstances = []
        
        for modelId in ids:
            modelObj = dbHandler.queryObject().filter(self._dbmodel.id == modelId).first()
            if not modelObj is None:
                modelInstances.append(modelObj)

        return modelInstances
        
    def _onRecordSelectedEntityBrowser(self, rec, row_number=-1):
        '''
        Slot raised when the user has clicked the select button
        in the 'EntityBrowser' dialog
        to add the selected record to the table's list.
        Add the record to the foreign key table using the mappings.
        '''
        #Check if the record exists using the primary key so as to ensure
        #only one instance is added to the table
        if isinstance(rec, int):
            recIndex = getIndex(self._recordIds(), rec)

            if recIndex != -1:
                return

            dbHandler = self._dbmodel()
            modelObj = dbHandler.queryObject().filter(self._dbmodel.id == rec).first()

        elif isinstance(rec, object):
            modelObj = rec

        else:
            return

        if not modelObj is None:
            #Raise before entity added signal
            self.beforeEntityAdded.emit(modelObj)
            
            #Validate for unique value configurations
            '''
            if not self._validate_unique_columns(modelObj, row_number):
                return
            '''

            if not self._supportsLists and self._tableModel.rowCount() > 0:
                self._removeRow(0)

            insert_position = self._insertModelToView(modelObj, row_number)

            if isinstance(rec, object):
                self._deferred_objects[insert_position] = modelObj

    def _validate_unique_columns(self,model,exclude_row = -1):
        """
        Loop through the attributes of the model to assert
        for existing row values that should be unique based on
        the configuration of unique columns.
        """
        for colIndex,replace in self._uniqueValueColIndices.items():
            attrName = self._dbmodel.displayMapping().keys()[colIndex]
            attrValue = getattr(model,attrName)

            # Check to see if there are cell formatters so
            # that the correct value is searched for in the model
            if attrName in self._cell_formatters:
                attrValue = self._cell_formatters[attrName](attrValue)

            matchingIndex = self.searchModel(colIndex, attrValue)

            if matchingIndex.isValid() and matchingIndex.row() != exclude_row:
                if replace:
                    existingId = matchingIndex.data()

                    #Delete old record from db
                    entityModels = self._modelInstanceFromIds([existingId])

                    if len(entityModels) > 0:
                        entityModels[0].delete()

                    self._removeRow(matchingIndex.row())

                    return True

                else:
                    #Break. Do not add item to the list.
                    return False

        return True

    def _insertModelToView(self, model_obj, row_number = -1):
        """
        Insert the given database model instance into the view
        at the given row number position.
        """
        if row_number == -1:
            row_number = self._tableModel.rowCount()
            self._tableModel.insertRows(row_number, 1)

        #In some instances, we will need to get the model object with
        # backrefs included else exceptions will be raised on missing
        # attributes
        q_objs = self._modelInstanceFromIds([model_obj.id])
        if len(q_objs) == 0:
            return

        model_obj = q_objs[0]

        for i, attr in enumerate(self._entity_attrs):
            prop_idx = self._tableModel.index(row_number, i)
            attr_val = getattr(model_obj, attr)

            '''
            Check if there are display formatters and apply if one exists
            for the given attribute.
            '''
            if attr in self._cell_formatters:
                formatter = self._cell_formatters[attr]
                attr_val = formatter.format_column_value(attr_val)

            self._tableModel.setData(prop_idx, attr_val)

        #Raise signal once entity has been inserted
        self.afterEntityAdded.emit(model_obj, row_number)

        self._tbFKEntity.resizeColumnsToContents()

        return row_number

    def insert_model_to_table(self, model_obj, row_number=-1):
        """
         Insert the given database model instance into the view
         at the given row number position.
         """
        if row_number == -1:
            row_number = self._tableModel.rowCount()
            self._tableModel.insertRows(row_number, 1)
        # In some instances, we will need to get the model object with
        # backrefs included else exceptions will be raised on missing
        # attributes
        q_objs = self._modelInstanceFromIds([model_obj.id])

        if len(q_objs) == 0:
            return

        model_obj = q_objs[0]

        for i, attr in enumerate(self._entity_attrs):
            prop_idx = self._tableModel.index(row_number, i)
            attr_val = getattr(model_obj, attr)

            # Check if there are display formatters and apply if one exists
            # for the given attribute.

            if attr in self._cell_formatters:
                formatter = self._cell_formatters[attr]
                attr_val = formatter.format_column_value(attr_val)

            self._tableModel.setData(prop_idx, attr_val)

        self._tbFKEntity.resizeColumnsToContents()

        return row_number

    def remove_rows(self):
        """
        Removes rows from the fk browser.
        """
        row_count = self._tbFKEntity.model().rowCount()

        self._tbFKEntity.model().removeRows(0, row_count)


    def vector_layer(self):
        """
        Returns a QgsVectorLayer based on the configuration information
        specified in the mapper including the system-wide data connection
        properties.
        """
        from stdm.data.pg_utils import vector_layer

        if self._dbmodel is None:
            msg = QApplication.translate("ForeignKeyMapper",
                                         "Primary database model object not defined.")
            return None, msg

        filter_layer = vector_layer(self._entity.name)
        if filter_layer is None:
            msg = QApplication.translate("ForeignKeyMapper",
                "Vector layer could not be constructed from the database table.")

            return None, msg

        if not filter_layer.isValid():
            trans_msg = QApplication.translate("ForeignKeyMapper",
                u"The vector layer for '{0}' table is invalid.")
            msg = trans_msg.format(self._entity.name)

            return None, msg

        return filter_layer, ""
    
    def onAddEntity(self):
        """
        Slot raised on selecting to add related entities that will be mapped to the primary
        database model instance.
        """
        self._entitySelector.buttonBox.button(QDialogButtonBox.Cancel).setVisible(False)

        #Clear any previous selections in the entity browser
        self._entitySelector.clear_selection()

        #Clear any previous notifications
        self._entitySelector.clear_notifications()

        self._entitySelector.exec_()
Exemple #3
0
class ForeignKeyMapper(QWidget):
    """
    Widget for selecting database records through an entity browser or
    using an ExpressionBuilder for filtering records.
    """
    # Custom signals
    beforeEntityAdded = pyqtSignal("PyQt_PyObject")
    afterEntityAdded = pyqtSignal("PyQt_PyObject", int)
    entityRemoved = pyqtSignal("PyQt_PyObject")
    deletedRows = pyqtSignal(list)

    def __init__(self,
                 entity,
                 parent=None,
                 notification_bar=None,
                 enable_list=True,
                 can_filter=False,
                 plugin=None):

        QWidget.__init__(self, parent)
        self.current_profile = current_profile()

        self._tbFKEntity = QTableView(self)
        self._tbFKEntity.setEditTriggers(QAbstractItemView.NoEditTriggers)
        self._tbFKEntity.setAlternatingRowColors(True)
        self._tbFKEntity.setSelectionBehavior(QAbstractItemView.SelectRows)
        self.plugin = plugin
        self._add_entity_btn = QToolButton(self)
        self._add_entity_btn.setToolTip(
            QApplication.translate("ForeignKeyMapper", "Add"))
        self._add_entity_btn.setIcon(GuiUtils.get_icon("add.png"))
        self._add_entity_btn.clicked.connect(self.onAddEntity)

        self._edit_entity_btn = QToolButton(self)
        self._edit_entity_btn.setVisible(False)
        self._edit_entity_btn.setToolTip(
            QApplication.translate("ForeignKeyMapper", "Edit"))
        self._edit_entity_btn.setIcon(GuiUtils.get_icon("edit.png"))

        self._filter_entity_btn = QToolButton(self)
        self._filter_entity_btn.setVisible(False)
        self._filter_entity_btn.setToolTip(
            QApplication.translate("ForeignKeyMapper", "Select by expression"))
        self._filter_entity_btn.setIcon(GuiUtils.get_icon("filter.png"))
        self._filter_entity_btn.clicked.connect(self.onFilterEntity)

        self._delete_entity_btn = QToolButton(self)
        self._delete_entity_btn.setToolTip(
            QApplication.translate("ForeignKeyMapper", "Remove"))
        self._delete_entity_btn.setIcon(GuiUtils.get_icon("remove.png"))
        self._delete_entity_btn.clicked.connect(self.onRemoveEntity)

        layout = QVBoxLayout(self)
        layout.setSpacing(4)
        layout.setMargin(5)

        self.grid_layout = QGridLayout()
        self.grid_layout.setHorizontalSpacing(5)
        self.grid_layout.addWidget(self._add_entity_btn, 0, 0, 1, 1)
        self.grid_layout.addWidget(self._filter_entity_btn, 0, 1, 1, 1)
        self.grid_layout.addWidget(self._edit_entity_btn, 0, 2, 1, 1)
        self.grid_layout.addWidget(self._delete_entity_btn, 0, 3, 1, 1)
        self.grid_layout.setColumnStretch(4, 5)

        layout.addLayout(self.grid_layout)
        layout.addWidget(self._tbFKEntity)
        self.social_tenure = self.current_profile.social_tenure

        self._tableModel = None
        self._notifBar = notification_bar
        self._headers = []
        self._entity_attrs = []
        self._cell_formatters = {}
        self._searchable_columns = OrderedDict()
        self._supportsLists = enable_list
        self._deleteOnRemove = False
        self._uniqueValueColIndices = OrderedDict()
        self.global_id = None
        self._deferred_objects = {}
        self._use_expression_builder = can_filter

        if self._use_expression_builder:
            self._filter_entity_btn.setVisible(True)
            self._edit_entity_btn.setVisible(False)
        self.set_entity(entity)

    def set_entity(self, entity):
        """
        Sets new entity and updates the ForeignKeyMapper with a new
        :param entity: The entity of the ForeignKeyMapper
        :type entity:Object
        """
        from stdm.ui.entity_browser import EntityBrowser

        self._entity = entity

        self._dbmodel = entity_model(entity)
        self._init_fk_columns()
        self._entitySelector = EntityBrowser(self._entity,
                                             parent=self,
                                             state=SELECT,
                                             plugin=self.plugin)

        # Connect signals
        self._entitySelector.recordSelected.connect(
            self._onRecordSelectedEntityBrowser)

    def _init_fk_columns(self):
        """
        Asserts if the entity columns actually do exist in the database. The
        method also initializes the table headers, entity column and cell
        formatters.
        """
        self._headers[:] = []
        self._entity_attrs[:] = []
        if self._dbmodel is None:
            msg = QApplication.translate(
                'ForeignKeyMapper', 'The data model for '
                'the entity could '
                'not be loaded, '
                'please contact '
                'your database '
                'administrator.')
            QMessageBox.critical(
                self, QApplication.translate('EntityBrowser',
                                             'Entity Browser'), msg)

            return

        table_name = self._entity.name
        columns = table_column_names(table_name)
        missing_columns = []

        header_idx = 0

        # Iterate entity column and assert if they exist
        for c in self._entity.columns.values():
            # Do not include virtual columns in list of missing columns
            if not c.name in columns and not isinstance(c, VirtualColumn):
                missing_columns.append(c.name)

            else:
                header = c.header()
                self._headers.append(header)
                '''
                If it is a virtual column then use column name as the header
                but fully qualified column name (created by SQLAlchemy
                relationship) as the entity attribute name.
                '''
                col_name = c.name

                if isinstance(c, MultipleSelectColumn):
                    col_name = c.model_attribute_name

                self._entity_attrs.append(col_name)

                # Get widget factory so that we can use the value formatter
                w_factory = ColumnWidgetRegistry.factory(c.TYPE_INFO)
                if not w_factory is None:
                    try:
                        formatter = w_factory(c)
                        self._cell_formatters[col_name] = formatter
                    except WidgetException as we:
                        msg = QApplication.translate(
                            'ForeignKeyMapper', 'Error in creating column:')
                        msg = '{0} {1}:{2}\n{3}'.format(
                            msg, self._entity.name, c.name, str(we))
                        QMessageBox.critical(
                            self,
                            QApplication.translate('ForeignKeyMapper',
                                                   'Widget Creation Error'),
                            msg)

                # Set searchable columns
                if c.searchable:
                    self._searchable_columns[header] = {
                        'name': c.name,
                        'header_index': header_idx
                    }

                header_idx += 1

        if len(missing_columns) > 0:
            msg = QApplication.translate(
                'ForeignKeyMapper',
                'The following columns have been defined in the '
                'configuration but are missing in corresponding '
                'database table, please re-run the configuration wizard '
                'to create them.\n{0}'.format('\n'.join(missing_columns)))

            QMessageBox.warning(
                self,
                QApplication.translate('ForeignKeyMapper', 'Entity Browser'),
                msg)

        self._tableModel = BaseSTDMTableModel([], self._headers, self)
        self._tbFKEntity.setModel(self._tableModel)
        # First (id) column will always be hidden
        self._tbFKEntity.hideColumn(0)

        self._tbFKEntity.horizontalHeader().setSectionResizeMode(
            QHeaderView.Interactive)
        self._tbFKEntity.horizontalHeader().setStretchLastSection(True)

        self._tbFKEntity.verticalHeader().setVisible(True)

    def databaseModel(self):
        '''
        Returns the database model that represents the foreign key entity.
        '''
        return self._dbmodel

    def setDatabaseModel(self, model):
        '''
        Set the database model that represents the foreign key entity.
        Model has to be a callable.
        '''
        self._dbmodel = model

    def cellFormatters(self):
        """
        Returns a dictionary of cell formatters used by the foreign key mapper.
        """
        return self._cell_formatters

    def cell_formatter(self, column):
        """
        :param column: Column name:
        :type column: str
        :return: Returns the corresponding formatter object based on the
        column name. None will be returned if there is no corresponding
        object.
        :rtype: object
        """
        return self._cell_formatters.get(column, None)

    def entitySelector(self):
        '''
        Returns the dialog for selecting the entity objects.
        '''
        return self._entitySelector

    def supportList(self):
        '''
        Returns whether the mapper supports only one item or multiple entities.
        Default is 'True'.
        '''
        return self._supportsLists

    def setSupportsList(self, supportsList):
        '''
        Sets whether the mapper supports only one item or multiple entities i.e.
        one-to-one (False) and one-to-many mapping (True).
        '''
        self._supportsLists = supportsList

    def setNotificationBar(self, notificationBar):
        '''
        Set the notification bar for displaying user messages.
        '''
        self._notifBar = notificationBar

    def viewModel(self):
        '''
        Return the view model used by the table view.
        '''
        return self._tableModel

    def set_expression_builder(self, state):
        """
        Set the mapper to use QGIS expression builder as the entity selector.
        """
        self._use_expression_builder = state

    def expression_builder_enabled(self):
        """
        Returns whether the mapper has been configured to use the expression builder
        """
        return self._use_expression_builder

    def deleteOnRemove(self):
        '''
        Returns the state whether a record should be deleted from the database when it
        is removed from the list.
        '''
        return self._deleteOnRemove

    def setDeleteonRemove(self, delete):
        '''
        Set whether whether a record should be deleted from the database when it
        is removed from the list.
        '''
        self._deleteOnRemove = delete

    def addUniqueColumnName(self, colName, replace=True):
        '''
        Set the name of the column whose values are to be unique.
        If 'replace' is True then the existing row will be replaced
        with one with the new value; else, the new row will not be added to the list.
        '''
        headers = list(self._dbmodel.displayMapping().values())
        colIndex = getIndex(headers, colName)

        if colIndex != -1:
            self.addUniqueColumnIndex(colIndex, replace)

    def addUniqueColumnIndex(self, colIndex, replace=True):
        '''
        Set the index of the column whose values are to be unique. The column indices are
        zero-based.
        If 'replace' is True then the existing row will be replaced with the
        new value; else, the new row will not be added to the list.
        For multiple replace rules defined, then the first one added to the collection is the
        one that will be applied.
        '''
        self._uniqueValueColIndices[colIndex] = replace

    def onFilterEntity(self):
        """
        Slot raised to load the expression builder dialog.
        """
        vl, msg = self.vector_layer()

        if vl is None:
            msg = msg + "\n" + QApplication.translate(
                "ForeignKeyMapper",
                "The expression builder cannot be used at this moment.")
            QMessageBox.critical(
                self,
                QApplication.translate("ForeignKeyMapper",
                                       "Expression Builder"), msg)

            return

        context = self._entity.short_name

        filter_dlg = ForeignKeyMapperExpressionDialog(vl,
                                                      self,
                                                      context=context)
        filter_dlg.setWindowTitle(
            QApplication.translate("ForeignKeyMapper", "Filter By Expression"))
        filter_dlg.recordSelected[int].connect(
            self._onRecordSelectedEntityBrowser)

        res = filter_dlg.exec_()

    def _removeRow(self, rowNumber):
        '''
        Remove the row at the given index.
        '''
        self._tableModel.removeRows(rowNumber, 1)

    def onRemoveEntity(self):
        '''
        Slot raised on clicking to remove the selected entity.
        '''
        selectedRowIndices = self._tbFKEntity.selectionModel().selectedRows(0)

        deleted_rows = []
        if len(selectedRowIndices) == 0:
            msg = QApplication.translate(
                "ForeignKeyMapper", "Please select the record to be removed.")
            self._notifBar.clear()
            self._notifBar.insertWarningNotification(msg)
            return

        for selectedRowIndex in selectedRowIndices:
            # Delete record from database if flag has been set to True
            recId = selectedRowIndex.data()

            dbHandler = self._dbmodel()
            delRec = dbHandler.queryObject().filter(
                self._dbmodel.id == recId).first()

            if not delRec is None:
                self.entityRemoved.emit(delRec)

                if self._deleteOnRemove:
                    delRec.delete()

            self._removeRow(selectedRowIndex.row())

            deleted_rows.append(selectedRowIndex.row())

        self.deletedRows.emit(deleted_rows)

    def _recordIds(self):
        '''
        Returns the primary keys of the records in the table.
        '''
        recordIds = []

        if self._tableModel:
            rowCount = self._tableModel.rowCount()

            for r in range(rowCount):
                # Get ID value
                modelIndex = self._tableModel.index(r, 0)
                modelId = modelIndex.data()
                recordIds.append(modelId)

        return recordIds

    def entities(self):
        '''
        Returns the model instance(s) depending on the configuration specified by the user.
        '''
        recIds = self._recordIds()

        modelInstances = self._modelInstanceFromIds(recIds)

        if len(modelInstances) == 0:
            if self._supportsLists:
                return []

            else:
                return None

        else:
            if self._supportsLists:
                return modelInstances

            else:
                return modelInstances[0]

    def setEntities(self, entities):
        '''
        Insert entities into the table.
        '''
        if isinstance(entities, list):
            for entity in entities:
                self._insertModelToView(entity)

        else:
            self._insertModelToView(entities)

    def searchModel(self, columnIndex, columnValue):
        '''
        Searches for 'columnValue' in the column whose index is specified by 'columnIndex' in all
        rows contained in the model.
        '''
        if isinstance(columnValue, QVariant):
            columnValue = str(columnValue.toString())

        if not isinstance(columnValue, str):
            columnValue = str(columnValue)

        columnValue = columnValue.strip()

        proxy = QSortFilterProxyModel(self)
        proxy.setSourceModel(self._tableModel)
        proxy.setFilterKeyColumn(columnIndex)
        proxy.setFilterFixedString(columnValue)
        # Will return model index containing the primary key.
        matchingIndex = proxy.mapToSource(proxy.index(0, 0))

        return matchingIndex

    def _modelInstanceFromIds(self, ids):
        '''
        Returns the model instance based the value of its primary key.
        '''
        dbHandler = self._dbmodel()

        modelInstances = []

        for modelId in ids:
            modelObj = dbHandler.queryObject().filter(
                self._dbmodel.id == modelId).first()
            if not modelObj is None:
                modelInstances.append(modelObj)

        return modelInstances

    def _onRecordSelectedEntityBrowser(self, rec, row_number=-1):
        '''
        Slot raised when the user has clicked the select button
        in the 'EntityBrowser' dialog
        to add the selected record to the table's list.
        Add the record to the foreign key table using the mappings.
        '''
        # Check if the record exists using the primary key so as to ensure
        # only one instance is added to the table
        if isinstance(rec, int):
            recIndex = getIndex(self._recordIds(), rec)

            if recIndex != -1:
                return

            dbHandler = self._dbmodel()
            modelObj = dbHandler.queryObject().filter(
                self._dbmodel.id == rec).first()

        elif isinstance(rec, object):
            modelObj = rec

        else:
            return

        if modelObj is not None:
            # Raise before entity added signal
            self.beforeEntityAdded.emit(modelObj)

            # Validate for unique value configurations
            '''
            if not self._validate_unique_columns(modelObj, row_number):
                return
            '''

            if not self._supportsLists and self._tableModel.rowCount() > 0:
                self._removeRow(0)

            insert_position = self._insertModelToView(modelObj, row_number)

            if isinstance(rec, object):
                self._deferred_objects[insert_position] = modelObj

    def _validate_unique_columns(self, model, exclude_row=-1):
        """
        Loop through the attributes of the model to assert
        for existing row values that should be unique based on
        the configuration of unique columns.
        """
        for colIndex, replace in list(self._uniqueValueColIndices.items()):
            attrName = list(self._dbmodel.displayMapping().keys())[colIndex]
            attrValue = getattr(model, attrName)

            # Check to see if there are cell formatters so
            # that the correct value is searched for in the model
            if attrName in self._cell_formatters:
                attrValue = self._cell_formatters[attrName](attrValue)

            matchingIndex = self.searchModel(colIndex, attrValue)

            if matchingIndex.isValid() and matchingIndex.row() != exclude_row:
                if replace:
                    existingId = matchingIndex.data()

                    # Delete old record from db
                    entityModels = self._modelInstanceFromIds([existingId])

                    if len(entityModels) > 0:
                        entityModels[0].delete()

                    self._removeRow(matchingIndex.row())

                    return True

                else:
                    # Break. Do not add item to the list.
                    return False

        return True

    def _insertModelToView(self, model_obj, row_number=-1):
        """
        Insert the given database model instance into the view
        at the given row number position.
        """
        if row_number == -1:
            row_number = self._tableModel.rowCount()
            self._tableModel.insertRows(row_number, 1)

        # In some instances, we will need to get the model object with
        # backrefs included else exceptions will be raised on missing
        # attributes
        q_objs = self._modelInstanceFromIds([model_obj.id])
        if len(q_objs) == 0:
            return

        model_obj = q_objs[0]

        for i, attr in enumerate(self._entity_attrs):
            prop_idx = self._tableModel.index(row_number, i)
            attr_val = getattr(model_obj, attr)
            '''
            Check if there are display formatters and apply if one exists
            for the given attribute.
            '''
            if attr in self._cell_formatters:
                formatter = self._cell_formatters[attr]
                attr_val = formatter.format_column_value(attr_val)

            self._tableModel.setData(prop_idx, attr_val)

        # Raise signal once entity has been inserted
        self.afterEntityAdded.emit(model_obj, row_number)

        self._tbFKEntity.resizeColumnsToContents()

        return row_number

    def insert_model_to_table(self, model_obj, row_number=-1):
        """
         Insert the given database model instance into the view
         at the given row number position.
         """
        if row_number == -1:
            row_number = self._tableModel.rowCount()
            self._tableModel.insertRows(row_number, 1)
        # In some instances, we will need to get the model object with
        # backrefs included else exceptions will be raised on missing
        # attributes
        q_objs = self._modelInstanceFromIds([model_obj.id])

        if len(q_objs) == 0:
            return

        model_obj = q_objs[0]

        for i, attr in enumerate(self._entity_attrs):
            prop_idx = self._tableModel.index(row_number, i)
            attr_val = getattr(model_obj, attr)

            # Check if there are display formatters and apply if one exists
            # for the given attribute.

            if attr in self._cell_formatters:
                formatter = self._cell_formatters[attr]
                attr_val = formatter.format_column_value(attr_val)

            self._tableModel.setData(prop_idx, attr_val)

        #self._tbFKEntity.resizeColumnsToContents()
        self._tbFKEntity.horizontalHeader().setSectionResizeMode(
            QHeaderView.Stretch)

        return row_number

    def remove_rows(self):
        """
        Removes rows from the fk browser.
        """
        row_count = self._tbFKEntity.model().rowCount()

        self._tbFKEntity.model().removeRows(0, row_count)

    def vector_layer(self):
        """
        Returns a QgsVectorLayer based on the configuration information
        specified in the mapper including the system-wide data connection
        properties.
        """
        from stdm.data.pg_utils import vector_layer

        if self._dbmodel is None:
            msg = QApplication.translate(
                "ForeignKeyMapper",
                "Primary database model object not defined.")
            return None, msg

        filter_layer = vector_layer(self._entity.name)
        if filter_layer is None:
            msg = QApplication.translate(
                "ForeignKeyMapper",
                "Vector layer could not be constructed from the database table."
            )

            return None, msg

        if not filter_layer.isValid():
            trans_msg = QApplication.translate(
                "ForeignKeyMapper",
                "The vector layer for '{0}' table is invalid.")
            msg = trans_msg.format(self._entity.name)

            return None, msg

        return filter_layer, ""

    def onAddEntity(self):
        """
        Slot raised on selecting to add related entities that will be mapped to the primary
        database model instance.
        """
        self._entitySelector.buttonBox.button(
            QDialogButtonBox.Cancel).setVisible(False)

        # Clear any previous selections in the entity browser
        self._entitySelector.clear_selection()

        # Clear any previous notifications
        self._entitySelector.clear_notifications()

        self._entitySelector.exec_()
Exemple #4
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class EntityBrowser(SupportsManageMixin, QDialog, Ui_EntityBrowser):
    """
    Dialog for browsing entity records in a table view.
    """

    # Custom signal that is raised when the dialog
    # is in SELECT state. It contains
    # the record id of the selected row.

    recordSelected = pyqtSignal(int)
    
    def __init__(self, entity, parent=None, state=MANAGE, load_records=True, plugin=None):
        QDialog.__init__(self,parent)
        self.setupUi(self)

        # Add maximize buttons
        self.setWindowFlags(
            self.windowFlags() |
            Qt.WindowSystemMenuHint |
            Qt.WindowMaximizeButtonHint
        )

        SupportsManageMixin.__init__(self, state)
        # Init document viewer setup
        self._view_docs_act = None
        viewer_title = QApplication.translate(
            'EntityBrowser',
            'Document Viewer'
        )
        self.doc_viewer_title = u'{0} {1}'.format(
            entity.ui_display(),
            viewer_title
        )
        self._doc_viewer = _EntityDocumentViewerHandler(
            self.doc_viewer_title,
            self
        )
        
        self.load_records = load_records
        #Initialize toolbar
        self.plugin = plugin
        self.tbActions = QToolBar()
        self.tbActions.setObjectName('eb_actions_toolbar')
        self.tbActions.setIconSize(QSize(16, 16))
        self.tbActions.setToolButtonStyle(Qt.ToolButtonIconOnly)
        self.vlActions.addWidget(self.tbActions)

        self._entity = entity
        self._dbmodel = entity_model(entity)
        self._state = state
        self._tableModel = None
        self._parent = parent
        self._data_initialized = False
        self._notifBar = NotificationBar(self.vlNotification)
        self._headers = []
        self._entity_attrs = []
        self._cell_formatters = {}
        self.filtered_records = []
        self._searchable_columns = OrderedDict()
        self._show_docs_col = False
        self.child_model = OrderedDict()
        #ID of a record to select once records have been added to the table
        self._select_item = None
        self.current_records = 0

        self.record_limit = self.get_records_limit() #get_entity_browser_record_limit()

        #Enable viewing of supporting documents
        if self.can_view_supporting_documents:
            self._add_view_supporting_docs_btn()

        # self._add_advanced_search_btn()
        #Connect signals
        self.buttonBox.accepted.connect(self.onAccept)
        self.tbEntity.doubleClicked[QModelIndex].connect(self.onDoubleClickView)

    def get_records_limit(self):
        records = get_entity_browser_record_limit()
        if records == 0:
            records = pg_table_count(self.entity.name)
        return records

    def children_entities(self):
        """
        :return: Returns a list of children entities
        that refer to the main entity as the parent.
        :rtype: list
        """
        return [ch for ch in self._entity.children()
                if ch.TYPE_INFO == Entity.TYPE_INFO]

    @property
    def entity(self):
        """
        :return: Returns the Entity object used in this browser.
        :rtype: Entity
        """
        return self._entity

    @property
    def can_view_supporting_documents(self):
        """
        :return: True if the browser supports the viewing of supporting
        documents.
        :rtype: bool
        """
        test_ent_obj = self._dbmodel()

        if self._entity.supports_documents \
                and hasattr(test_ent_obj, 'documents'):
            return True

        return False

    def _add_view_supporting_docs_btn(self):
        #Add button for viewing supporting documents if supported
        view_docs_str = QApplication.translate(
            'EntityBrowser',
            'View Documents'
        )
        self._view_docs_act = QAction(
            QIcon(':/plugins/stdm/images/icons/document.png'),
            view_docs_str,
            self
        )

        #Connect signal for showing document viewer
        self._view_docs_act.triggered.connect(self.on_load_document_viewer)

        self.tbActions.addAction(self._view_docs_act)


    # def _add_advanced_search_btn(self):
    #     #Add button for viewing supporting documents if supported
    #     search_str = QApplication.translate(
    #         'EntityBrowser',
    #         'Advanced Search'
    #     )
    #     self._search_act = QAction(
    #         QIcon(':/plugins/stdm/images/icons/advanced_search.png'),
    #         search_str,
    #         self
    #     )

    #     #Connect signal for showing document viewer
    #     self._search_act.triggered.connect(self.on_advanced_search)

    #     self.tbActions.addAction(self._search_act)

    def dateFormatter(self):
        """
        Function for formatting date values
        """
        return self._dateFormatter

    def setDateFormatter(self,formatter):
        """
        Sets the function for formatting date values. Overrides the default function.
        """
        self._dateFormatter = formatter

    def state(self):
        '''
        Returns the current state that the dialog has been configured in.
        '''
        return self._state

    def setState(self,state):
        '''
        Set the state of the dialog.
        '''
        self._state = state

    def set_selection_record_id(self, id):
        """
        Set the ID of a record to be selected only once all records have been
        added to the table view.
        :param id: Record id to be selected.
        :type id: int
        """
        self._select_item = id

    def title(self):
        '''
        Set the title of the entity browser dialog.
        Protected method to be overridden by subclasses.
        '''
        records = QApplication.translate('EntityBrowser', 'Records')
        if self._entity.label != '':
            title = self._entity.label
        else:
            title = self._entity.ui_display()

        return u'{} {}'.format(title, records)

    def setCellFormatters(self,formattermapping):
        '''
        Dictionary of attribute mappings and corresponding functions for
        formatting the attribute value to the display value.
        '''
        self._cell_formatters = formattermapping

    def addCellFormatter(self,attributeName,formatterFunc):
        '''
        Add a new cell formatter configuration to the collection
        '''
        self._cell_formatters[attributeName] = formatterFunc

    def showEvent(self,showEvent):
        '''
        Override event for loading the database records once the dialog is visible.
        This is for improved user experience i.e. to prevent the dialog from taking
        long to load.
        '''
        self.setWindowTitle(unicode(self.title()))

        if self._data_initialized:
            return
        try:
            if not self._dbmodel is None:
                # cProfile.runctx('self._initializeData()', globals(), locals())
                self._initializeData()

        except Exception as ex:
            pass

        self._data_initialized = True

    def hideEvent(self,hideEvent):
        '''
        Override event which just sets a flag to indicate that the data records have already been
        initialized.
        '''
        pass

    def clear_selection(self):
        """
        Deselects all selected items in the table view.
        """
        self.tbEntity.clearSelection()

    def clear_notifications(self):
        """
        Clears all notifications messages in the dialog.
        """
        self._notifBar.clear()

    def recomputeRecordCount(self, init_data=False):
        '''
        Get the number of records in the specified table and updates the window title.
        '''
        entity = self._dbmodel()

        # Get number of records
        numRecords = entity.queryObject().count()
        if init_data:
            if self.current_records < 1:
                if numRecords > self.record_limit:
                    self.current_records = self.record_limit
                else:
                    self.current_records = numRecords

        rowStr = QApplication.translate('EntityBrowser', 'row') \
            if numRecords == 1 \
            else QApplication.translate('EntityBrowser', 'rows')
        showing = QApplication.translate('EntityBrowser', 'Showing')
        windowTitle = u"{0} - {1} {2} of {3} {4}".format(
            self.title(), showing, self.current_records, numRecords, rowStr
        )

        self.setWindowTitle(windowTitle)

        return numRecords

    def _init_entity_columns(self):
        """
        Asserts if the entity columns actually do exist in the database. The
        method also initializes the table headers, entity column and cell
        formatters.
        """
        self._headers[:] = []
        table_name = self._entity.name
        columns = table_column_names(table_name)
        missing_columns = []

        header_idx = 0

        #Iterate entity column and assert if they exist

        for c in self._entity.columns.values():


            # Exclude geometry columns
            if isinstance(c, GeometryColumn):
                continue

            # Do not include virtual columns in list of missing columns
            if not c.name in columns and not isinstance(c, VirtualColumn):
                missing_columns.append(c.name)

            else:
                header = c.ui_display()
                self._headers.append(header)
                col_name = c.name

                '''
                If it is a virtual column then use column name as the header
                but fully qualified column name (created by SQLAlchemy
                relationship) as the entity attribute name.
                '''

                if isinstance(c, MultipleSelectColumn):
                    col_name = c.model_attribute_name

                self._entity_attrs.append(col_name)

                # Get widget factory so that we can use the value formatter
                w_factory = ColumnWidgetRegistry.factory(c.TYPE_INFO)
                if not w_factory is None:
                    formatter = w_factory(c)
                    self._cell_formatters[col_name] = formatter

                # Set searchable columns
                if c.searchable:
                    self._searchable_columns[c.ui_display()] = {
                        'name': c.name,
                        'header_index': header_idx
                    }

                header_idx += 1

        if len(missing_columns) > 0:
            msg = QApplication.translate(
                'EntityBrowser',
                u'The following columns have been defined in the '
                u'configuration but are missing in corresponding '
                u'database table, please re-run the configuration wizard '
                u'to create them.\n{0}'.format(
                    '\n'.join(missing_columns)
                )
            )

            QMessageBox.warning(
                self,
                QApplication.translate('EntityBrowser','Entity Browser'),
                msg
            )

    def _select_record(self, id):
        #Selects record with the given ID.
        if id is None:
            return

        m = self.tbEntity.model()
        s = self.tbEntity.selectionModel()

        start_idx = m.index(0, 0)
        idxs = m.match(
            start_idx,
            Qt.DisplayRole,
            id,
            1,
            Qt.MatchExactly
        )

        if len(idxs) > 0:
            sel_idx = idxs[0]
             #Select item
            s.select(
                sel_idx,
                QItemSelectionModel.ClearAndSelect|QItemSelectionModel.Rows
            )

    # def on_advanced_search(self):
    #     search = AdvancedSearch(self._entity, parent=self)
    #     search.show()

    def on_load_document_viewer(self):
        #Slot raised to show the document viewer for the selected entity
        sel_rec_ids = self._selected_record_ids()

        if len(sel_rec_ids) == 0:
            return

        #Get document objects
        ent_obj = self._dbmodel()

        for sel_id in sel_rec_ids:
            er = ent_obj.queryObject().filter(self._dbmodel.id == sel_id).first()
            if not er is None:
                docs = er.documents

                #Notify there are no documents for the selected doc
                if len(docs) == 0:
                    msg = QApplication.translate(
                        'EntityBrowser',
                        'There are no supporting documents for the selected record.'
                    )

                    QMessageBox.warning(
                        self,
                        self.doc_viewer_title,
                        msg
                    )

                    continue

                self._doc_viewer.load(docs)

    def _initializeData(self, filtered_records=None):
        '''
        Set table model and load data into it.
        '''
        if self._dbmodel is None:
            msg = QApplication.translate(
                'EntityBrowser',
                'The data model for the entity could not be loaded, \n'
                'please contact your database administrator.'
            )
            QMessageBox.critical(
                self,
                QApplication.translate('EntityBrowser', 'Entity Browser'),
                msg
            )

        else:

            self._init_entity_columns()

            # Load entity data. There might be a better way in future in order
            # to ensure that there is a balance between user data discovery
            # experience and performance.

            if filtered_records is not None:
                self.current_records = filtered_records.rowcount

            numRecords = self.recomputeRecordCount(init_data=True)

            # Load progress dialog
            progressLabel = QApplication.translate(
                "EntityBrowser", "Fetching Records..."
            )
            progressDialog = QProgressDialog(
                progressLabel, None, 0, numRecords, self
            )

            QApplication.processEvents()
            progressDialog.show()
            progressDialog.setValue(0)

            # Add records to nested list for enumeration in table model
            load_data = True
            if self.plugin is not None:
                if self._entity.name in self.plugin.entity_table_model.keys():
                    if filtered_records is None:
                        self._tableModel = self.plugin.entity_table_model[
                            self._entity.name
                        ]
            if isinstance(self._parent, EntityEditorDialog):
                load_data = True

            if load_data:
                # Only one filter is possible.
                if len(self.filtered_records) > 0:
                    entity_records = self.filtered_records
                else:
                    entity_cls = self._dbmodel()
                    entity_records = entity_cls.queryObject().filter().limit(
                        self.record_limit
                    ).all()

            # if self._tableModel is None:
                entity_records_collection = []
                for i, er in enumerate(entity_records):
                    if i == self.record_limit:
                        break
                    QApplication.processEvents()
                    entity_row_info = []
                    progressDialog.setValue(i)
                    try:
                        for attr in self._entity_attrs:
                            attr_val = getattr(er, attr)

                            # Check if there are display formatters and apply if
                            # one exists for the given attribute.
                            if attr_val is not None: # No need of formatter for None value
                                if attr in self._cell_formatters:
                                    formatter = self._cell_formatters[attr]
                                    attr_val = formatter.format_column_value(attr_val)
                            entity_row_info.append(attr_val)
                    except Exception as ex:
                        QMessageBox.critical(
                            self,
                            QApplication.translate(
                                'EntityBrowser', 'Loading Records'
                            ),
                            unicode(ex.message))
                        return

                    entity_records_collection.append(entity_row_info)


                self._tableModel = BaseSTDMTableModel(
                    entity_records_collection, self._headers, self
                )

                if self.plugin is not None:
                    self.plugin.entity_table_model[self._entity.name] = \
                            self._tableModel

            # Add filter columns
            for header, info in self._searchable_columns.iteritems():
                column_name, index = info['name'], info['header_index']
                if column_name != 'id':
                    self.cboFilterColumn.addItem(header, info)

            #Use sortfilter proxy model for the view
            self._proxyModel = VerticalHeaderSortFilterProxyModel()
            self._proxyModel.setDynamicSortFilter(True)
            self._proxyModel.setSourceModel(self._tableModel)
            self._proxyModel.setSortCaseSensitivity(Qt.CaseInsensitive)

            #USe first column in the combo for filtering
            if self.cboFilterColumn.count() > 0:
                self.set_proxy_model_filter_column(0)

            self.tbEntity.setModel(self._proxyModel)
            if numRecords < self.record_limit:
                self.tbEntity.setSortingEnabled(True)
                self.tbEntity.sortByColumn(1, Qt.AscendingOrder)

            #First (ID) column will always be hidden
            self.tbEntity.hideColumn(0)

            self.tbEntity.horizontalHeader().setResizeMode(QHeaderView.Interactive)

            self.tbEntity.resizeColumnsToContents()

            #Connect signals
            self.connect(self.cboFilterColumn, SIGNAL('currentIndexChanged (int)'), self.onFilterColumnChanged)
            self.connect(self.txtFilterPattern, SIGNAL('textChanged(const QString&)'), self.onFilterRegExpChanged)

            #Select record with the given ID if specified
            if not self._select_item is None:
                self._select_record(self._select_item)

            if numRecords > 0:
                # Set maximum value of the progress dialog
                progressDialog.setValue(numRecords)
            else:
                progressDialog.hide()

    def _header_index_from_filter_combo_index(self, idx):
        col_info = self.cboFilterColumn.itemData(idx)

        return col_info['name'], col_info['header_index']

    def set_proxy_model_filter_column(self, index):
        #Set the filter column for the proxy model using the combo index
        name, header_idx = self._header_index_from_filter_combo_index(index)
        self._proxyModel.setFilterKeyColumn(header_idx)

    def onFilterColumnChanged(self, index):
        '''
        Set the filter column for the proxy model.
        '''
        self.set_proxy_model_filter_column(index)

    def _onFilterRegExpChanged(self,text):
        cProfile.runctx('self._onFilterRegExpChanged(text)', globals(), locals())

    def onFilterRegExpChanged(self,text):
        '''
        Slot raised whenever the filter text changes.
        '''
        regExp = QRegExp(text,Qt.CaseInsensitive,QRegExp.FixedString)
        self._proxyModel.setFilterRegExp(regExp)

    def onDoubleClickView(self,modelindex):
        '''
        Slot raised upon double clicking the table view.
        To be implemented by subclasses.
        '''
        pass

    def _selected_record_ids(self):
        '''
        Get the IDs of the selected row in the table view.
        '''
        self._notifBar.clear()

        selected_ids = []
        sel_row_indices = self.tbEntity.selectionModel().selectedRows(0)

        if len(sel_row_indices) == 0:
            msg = QApplication.translate("EntityBrowser",
                                         "Please select a record from the table.")

            self._notifBar.insertWarningNotification(msg)

            return selected_ids

        for proxyRowIndex in sel_row_indices:
            #Get the index of the source or else the row items will have unpredictable behavior
            row_index = self._proxyModel.mapToSource(proxyRowIndex)
            entity_id = row_index.data(Qt.DisplayRole)
            selected_ids.append(entity_id)

        return selected_ids

    def onAccept(self):
        '''
        Slot raised when user clicks to accept the dialog. The resulting action will be dependent
        on the state that the browser is currently configured in.
        '''
        selIDs = self._selected_record_ids()
        if len(selIDs) == 0:
            return

        if self._mode == SELECT:
            #Get all selected records
            for sel_id in selIDs:
                self.recordSelected.emit(sel_id)

            rec_selected = QApplication.translate(
                'EntityBrowser',
                'record(s) selected'
            )

            msg = u'{0:d} {1}.'.format(len(selIDs), rec_selected)
            self._notifBar.insertInformationNotification(msg)

    def addModelToView(self, model_obj):
        '''
        Convenience method for adding model info into the view.
        '''
        insertPosition = self._tableModel.rowCount()
        self._tableModel.insertRows(insertPosition, 1)

        for i, attr in enumerate(self._entity_attrs):

            prop_idx = self._tableModel.index(insertPosition, i)
            attr_val = getattr(model_obj, attr)

            '''
            Check if there are display formatters and apply if one exists
            for the given attribute.
            '''
            if attr in self._cell_formatters:
                formatter = self._cell_formatters[attr]
                attr_val = formatter.format_column_value(attr_val)

            self._tableModel.setData(prop_idx, attr_val)
        return insertPosition

    def _model_from_id(self, record_id, row_number):
        '''
        Convenience method that returns the model object based on its ID.
        '''
        dbHandler = self._dbmodel()
        modelObj = dbHandler.queryObject().filter(
            self._dbmodel.id == record_id
        ).first()

        if modelObj is None:
            modelObj = self.child_model[row_number+1]

        return modelObj