class SimpleEditor ( EditorWithList, IValueChangeListener ):
""" Simple style of editor for checklists, which displays a combo box.
"""
#---------------------------------------------------------------------------
# Trait definitions:
#---------------------------------------------------------------------------
# Checklist item names
names = List( Unicode )
# Checklist item values
values = List
#---------------------------------------------------------------------------
# Finishes initializing the editor by creating the underlying toolkit
# widget:
#---------------------------------------------------------------------------
def init ( self, parent ):
""" Finishes initializing the editor by creating the underlying toolkit
widget.
"""
self.create_control( parent )
super( SimpleEditor, self ).init( parent )
self.set_tooltip()
#---------------------------------------------------------------------------
# Creates the initial editor control:
#---------------------------------------------------------------------------
def create_control ( self, parent ):
""" Creates the initial editor control.
"""
self.control = ComboBox()
self.control.setMultiSelect(False)
self.control.setNullSelectionAllowed(True)
self.control.setImmediate(True)
self.control.addListener(self, IValueChangeListener)
#---------------------------------------------------------------------------
# Handles the list of legal check list values being updated:
#---------------------------------------------------------------------------
def list_updated ( self, values ):
""" Handles updates to the list of legal checklist values.
"""
sv = self.string_value
if (len( values ) > 0) and isinstance( values[0], basestring ):
values = [ ( x, sv( x, capitalize ) ) for x in values ]
self.values = valid_values = [ x[0] for x in values ]
self.names = [ x[1] for x in values ]
# Make sure the current value is still legal:
modified = False
cur_value = parse_value( self.value )
for i in range( len( cur_value ) - 1, -1, -1 ):
if cur_value[i] not in valid_values:
try:
del cur_value[i]
modified = True
except TypeError:
logger.warn('Unable to remove non-current value [%s] from '
'values %s', cur_value[i], values)
if modified:
if isinstance( self.value, basestring ):
cur_value = ','.join( cur_value )
self.value = cur_value
self.rebuild_editor()
#---------------------------------------------------------------------------
# Rebuilds the editor after its definition is modified:
#---------------------------------------------------------------------------
def rebuild_editor ( self ):
""" Rebuilds the editor after its definition is modified.
"""
control = self.control
c = IndexedContainer()
for name in self.names:
c.addItem(name)
control.setContainerDataSource(c)
self.update_editor()
#---------------------------------------------------------------------------
# Handles the user selecting a new value from the combo box:
#---------------------------------------------------------------------------
def valueChange(self, event):
v = str(event.getProperty())
self.update_object(v)
def update_object ( self, text ):
""" Handles the user selecting a new value from the combo box.
"""
if unicode(text) in self.names:
value = self.values[self.names.index(unicode(text))]
if not isinstance(self.value, basestring):
value = [value]
elif not isinstance(self.value, basestring):
value = []
else:
value = ''
self.value = value
#---------------------------------------------------------------------------
# Updates the editor when the object trait changes external to the editor:
#---------------------------------------------------------------------------
def update_editor ( self ):
""" Updates the editor when the object trait changes externally to the
editor.
"""
try:
self.control.select( parse_value(self.value)[0] )
except:
pass
class MuntjacComboBox(MuntjacControl, AbstractTkComboBox):
""" A Muntjac implementation of ComboBox.
Use a combo box to select a single item from a collection of items.
"""
#--------------------------------------------------------------------------
# Setup methods
#--------------------------------------------------------------------------
def create(self, parent):
""" Creates a QComboBox.
"""
self.widget = ComboBox()
self.widget.setImmediate(True)
parent.addComponent(self.widget)
def initialize(self):
""" Intializes the widget with the attributes of this instance.
"""
super(MuntjacComboBox, self).initialize()
shell = self.shell_obj
self.set_items(shell.labels)
self.set_selection(shell.index)
def bind(self):
""" Connects the event handlers for the combo box.
"""
super(MuntjacComboBox, self).bind()
self.widget.currentIndexChanged.connect(self.on_selected)
#--------------------------------------------------------------------------
# Implementation
#--------------------------------------------------------------------------
def shell_index_changed(self, index):
""" The change handler for the 'index' attribute on the shell
object.
"""
self.set_selection(index)
def shell_labels_changed(self, labels):
""" The change handler for the 'labels' attribute on the shell
object.
"""
self.set_items(labels)
def on_selected(self):
""" The event handler for a combo box selection event.
"""
if not guard.guarded(self, 'updating'):
shell = self.shell_obj
curr_index = self._selected_index()
shell.index = curr_index
# Only fire the selected event if we have a valid selection
if curr_index != -1:
shell.selected = shell.value
def set_items(self, str_items):
""" Sets the items in the combo box.
"""
# We need to avoid a feedback loop when updating the items in
# the combo box. Qt will emit index changed signals when the
# items are updated. But, the shell object has already computed
# the proper index for the new items, so we use that to update
# the index of the control after updating the items. The flag
# is read by the on_selected handler to ignore updates during
# this process.
with guard(self, 'updating'):
widget = self.widget
widget.removeAllItems()
for item in str_items:
widget.addItem(item)
ids = widget.getItemIds()
widget.select(ids[self.shell_obj.index])
def set_selection(self, index):
""" Sets the value in the combo box, or resets the combo box
if the value is not in the list of items.
"""
# We need to avoid a feedback loop when updating the selection
# in the combo box. Qt will emit index changed signals when the
# selectino is updated. But, the shell object has already computed
# the proper index for the new selection so we don't need to feed
# back while doing this.
with guard(self, 'updating'):
ids = self.widget.getItemIds()
self.widget.select(ids[index])
#--------------------------------------------------------------------------
# Helper Methods
#--------------------------------------------------------------------------
def _selected_index(self):
widget = self.widget
ids = widget.getItemIds()
val = widget.getValue()
if val in ids:
curr_index = ids.index(val)
else:
curr_index = -1
return curr_index
