def __init__(self, surface):
super(SurfaceGraph, self).__init__()
self.m_graph = surface
self.m_graph.setAxisX(QValue3DAxis())
self.m_graph.setAxisY(QValue3DAxis())
self.m_graph.setAxisZ(QValue3DAxis())
self.m_sqrtSinProxy = QSurfaceDataProxy()
self.m_sqrtSinSeries = QSurface3DSeries(self.m_sqrtSinProxy)
self.fillSqrtSinProxy()
heightMapImage = QImage(
QFileInfo(__file__).absolutePath() + '/mountain.png')
self.m_heightMapProxy = QHeightMapSurfaceDataProxy(heightMapImage)
self.m_heightMapSeries = QSurface3DSeries(self.m_heightMapProxy)
self.m_heightMapSeries.setItemLabelFormat(
"(@xLabel, @zLabel): @yLabel")
self.m_heightMapProxy.setValueRanges(34.0, 40.0, 18.0, 24.0)
self.m_heightMapWidth = heightMapImage.width()
self.m_heightMapHeight = heightMapImage.height()
self.m_axisMinSliderX = None
self.m_axisMaxSliderX = None
self.m_axisMinSliderZ = None
self.m_axisMaxSliderZ = None
self.m_rangeMinX = 0.0
self.m_rangeMinZ = 0.0
self.m_stepX = 0.0
self.m_stepZ = 0.0
def __init__(self, scatter):
super(ScatterDataModifier, self).__init__()
self.m_graph = scatter
self.m_inputHandler = CustomInputHandler()
self.m_graph.activeTheme().setType(Q3DTheme.ThemeDigia)
self.m_graph.setShadowQuality(QAbstract3DGraph.ShadowQualityMedium)
self.m_graph.scene().activeCamera().setCameraPreset(
Q3DCamera.CameraPresetFront)
self.m_graph.setAxisX(QValue3DAxis())
self.m_graph.setAxisY(QValue3DAxis())
self.m_graph.setAxisZ(QValue3DAxis())
self.m_graph.axisX().setRange(-10.0, 10.0)
self.m_graph.axisY().setRange(-5.0, 5.0)
self.m_graph.axisZ().setRange(-5.0, 5.0)
series = QScatter3DSeries()
series.setItemLabelFormat("@xLabel, @yLabel, @zLabel")
series.setMesh(QAbstract3DSeries.MeshCube)
series.setItemSize(0.15)
self.m_graph.addSeries(series)
self.m_animationCameraX = QPropertyAnimation(
self.m_graph.scene().activeCamera(), 'xRotation')
self.m_animationCameraX.setDuration(20000)
self.m_animationCameraX.setStartValue(0.0)
self.m_animationCameraX.setEndValue(360.0)
self.m_animationCameraX.setLoopCount(-1)
upAnimation = QPropertyAnimation(self.m_graph.scene().activeCamera(),
'yRotation')
upAnimation.setDuration(9000)
upAnimation.setStartValue(5.0)
upAnimation.setEndValue(45.0)
downAnimation = QPropertyAnimation(self.m_graph.scene().activeCamera(),
'yRotation')
downAnimation.setDuration(9000)
downAnimation.setStartValue(45.0)
downAnimation.setEndValue(5.0)
self.m_animationCameraY = QSequentialAnimationGroup()
self.m_animationCameraY.setLoopCount(-1)
self.m_animationCameraY.addAnimation(upAnimation)
self.m_animationCameraY.addAnimation(downAnimation)
self.m_animationCameraX.start()
self.m_animationCameraY.start()
self.m_graph.setActiveInputHandler(self.m_inputHandler)
self.m_selectionTimer = QTimer()
self.m_selectionTimer.setInterval(10)
self.m_selectionTimer.timeout.connect(self.triggerSelection)
self.m_selectionTimer.start()
def __init__(self, surface):
super(SurfaceGraph, self).__init__()
self.m_graph = surface
self.m_graph.setAxisX(QValue3DAxis())
self.m_graph.setAxisY(QValue3DAxis())
self.m_graph.setAxisZ(QValue3DAxis())
self.m_sqrtSinProxy = QSurfaceDataProxy()
self.m_sqrtSinSeries = QSurface3DSeries(self.m_sqrtSinProxy)
self.fillSqrtSinProxy()
self.m_graph.addSeries(self.m_sqrtSinSeries)
def __init__(self,parent=None):
super(Qtw.QWidget, self).__init__(parent)
self.setWindowTitle("Equation interpreter")
self.mainLayout=Qtw.QGridLayout(self)
self.setLayout(self.mainLayout)
# Create label #
self.mainlabel = Qtw.QLabel("Type your equation here, must be a function of (x,y):")
self.mainLayout.addWidget(self.mainlabel,0,0)
# Create textbox #
self.textbox = QLineEdit(self)
self.mainLayout.addWidget(self.textbox,1,0)
# Create LaTeX viewer #
self.viewer = Qtw.QLabel()
self.viewer.setPixmap(mathTex_to_QPixmap('$ ... $', 15))
self.mainLayout.addWidget(self.viewer,2,0)
# Create graph visualizer #
self.cubesize = CubeSize(4,8,8)
self.graph = Q3DSurface()
self.screenSize = self.graph.screen().size()
self.graph.setAspectRatio(2.0)
self.graph.setAxisX(QValue3DAxis())
self.graph.setAxisY(QValue3DAxis())
self.graph.setAxisZ(QValue3DAxis())
self.graph.axisX().setTitle("Depth")
self.graph.axisY().setTitle("Height")
self.graph.axisZ().setTitle("Width")
self.functionProxy = QSurfaceDataProxy()
self.functionSeries = QSurface3DSeries(self.functionProxy)
self.graphvisualizer = Qtw.QWidget.createWindowContainer(self.graph)
self.graphvisualizer.setMinimumSize(QSize(self.screenSize.width()/3, self.screenSize.height()/2))
self.mainLayout.addWidget(self.graphvisualizer,3,0)
# Create a button in the window #
self.button = QPushButton('Display equation', self)
self.mainLayout.addWidget(self.button,1,1)
# Connect button to function on_click #
self.button.clicked.connect(self.on_click)
# Connect the enter key to button #
self.buttonShortcut = QShortcut(QKeySequence(QtCore.Qt.Key_Return), self.button)
self.buttonShortcut.activated.connect(self.on_click)
def setupGraph(self):
"""Load data and set up the window for the bar graph."""
header_label = QLabel(
"Average Monthly Temperatures in Reykjavík, Iceland 1990-2000 (˚C)"
)
header_label.setAlignment(Qt.AlignCenter)
# Load the data about average temperatures in Reykjavík from the CSV file
temperature_data = self.loadCSVFile()
# Select 11 sample years: 1990-2000. Don't select the first and last columns
rows, columns = temperature_data.shape
years = temperature_data[rows - 11:rows, 1]
monthly_temps = temperature_data[rows - 11:rows,
2:columns - 1].astype(float)
bar_graph = Q3DBars() # Create instance for bar graph
bar_graph.scene().activeCamera().setCameraPreset(
Q3DCamera.CameraPresetFront)
# Create a list of QBarDataItem objects
data_items = []
for row in monthly_temps:
data_items.append([QBarDataItem(value) for value in row])
months = [
"January", "February", "March", "April", "May", "June", "July",
"August", "September", "October", "November", "December"
]
# Create instance of QBar3DSeries, change the base color and color of
# selected items, and add data and labels to the series
series = QBar3DSeries()
series.setBaseColor(QColor("#17A4D9"))
series.setSingleHighlightColor(QColor("#F8A307"))
series.dataProxy().addRows(data_items)
series.dataProxy().setRowLabels(years) # rowLabel
series.dataProxy().setColumnLabels(months) # colLabel
# Create the valueLabel. Use QValue3dAxis so we can format the axis's label
temperature_axis = QValue3DAxis()
temperature_axis.setRange(-10, 20)
temperature_axis.setLabelFormat(u"%.1f \N{degree sign}C")
bar_graph.setValueAxis(temperature_axis)
# When items in the graph are selected, a label appears overhead with information
# about that item. Set the format of information in the label
series.setItemLabelFormat(
"Reykjavík - @colLabel @rowLabel: @valueLabel")
bar_graph.addSeries(series) # Add the series to the bar graph
# 3D graph classes inherit QWindow, so we must use createWindowContainer() to
# create a holder for the 3D graph in our window since they can't be used
# as a normal widget
container = self.createWindowContainer(bar_graph)
v_box = QVBoxLayout()
v_box.addWidget(header_label)
v_box.addWidget(container, 1)
self.setLayout(v_box)
def __init__(self, bargraph):
super(GraphModifier, self).__init__()
self.m_graph = bargraph
self.m_xRotation = 0.0
self.m_yRotation = 0.0
self.m_fontSize = 30
self.m_segments = 4
self.m_subSegments = 3
self.m_minval = -20.0
self.m_maxval = 20.0
self.m_temperatureAxis = QValue3DAxis()
self.m_yearAxis = QCategory3DAxis()
self.m_monthAxis = QCategory3DAxis()
self.m_primarySeries = QBar3DSeries()
self.m_secondarySeries = QBar3DSeries()
self.m_barMesh = QAbstract3DSeries.MeshBevelBar
self.m_smooth = False
self.m_graph.setShadowQuality(QAbstract3DGraph.ShadowQualitySoftMedium)
self.m_graph.activeTheme().setBackgroundEnabled(False)
self.m_graph.activeTheme().setFont(
QFont('Times New Roman', self.m_fontSize))
self.m_graph.activeTheme().setLabelBackgroundEnabled(True)
self.m_graph.setMultiSeriesUniform(True)
self.m_temperatureAxis.setTitle("Average temperature")
self.m_temperatureAxis.setSegmentCount(self.m_segments)
self.m_temperatureAxis.setSubSegmentCount(self.m_subSegments)
self.m_temperatureAxis.setRange(self.m_minval, self.m_maxval)
self.m_temperatureAxis.setLabelFormat(u"%.1f \N{degree sign}C")
self.m_yearAxis.setTitle("Year")
self.m_monthAxis.setTitle("Month")
self.m_graph.setValueAxis(self.m_temperatureAxis)
self.m_graph.setRowAxis(self.m_yearAxis)
self.m_graph.setColumnAxis(self.m_monthAxis)
self.m_primarySeries.setItemLabelFormat(
"Oulu - @colLabel @rowLabel: @valueLabel")
self.m_primarySeries.setMesh(QAbstract3DSeries.MeshBevelBar)
self.m_primarySeries.setMeshSmooth(False)
self.m_secondarySeries.setItemLabelFormat(
"Helsinki - @colLabel @rowLabel: @valueLabel")
self.m_secondarySeries.setMesh(QAbstract3DSeries.MeshBevelBar)
self.m_secondarySeries.setMeshSmooth(False)
self.m_secondarySeries.setVisible(False)
self.m_graph.addSeries(self.m_primarySeries)
self.m_graph.addSeries(self.m_secondarySeries)
self.m_preset = Q3DCamera.CameraPresetFront
self.changePresetCamera()
self.resetTemperatureData()
def __init__(self, bargraph):
super(GraphModifier, self).__init__()
self.m_graph = bargraph # Q3DBars 实例
self.m_xRotation = 0.0 # 水平旋转角度
self.m_yRotation = 0.0 # 垂直旋转角度
self.m_fontSize = 30
self.m_segments = 4
self.m_subSegments = 3
self.m_minval = -20.0
self.m_maxval = 20.0
self.m_temperatureAxis = QValue3DAxis() # 温度轴
self.m_yearAxis = QCategory3DAxis() # 年份轴
self.m_monthAxis = QCategory3DAxis() # 月份轴
self.m_primarySeries = QBar3DSeries() # 主序列
self.m_secondarySeries = QBar3DSeries() # 次序列
self.m_barMesh = QAbstract3DSeries.MeshBevelBar # 预定义的网格类型
self.m_smooth = False # 是否平滑
# 阴影以柔化的边缘高质量渲染
self.m_graph.setShadowQuality(QAbstract3DGraph.ShadowQualitySoftMedium)
# 当前主题Q3DTheme设置背景是否可见
self.m_graph.activeTheme().setBackgroundEnabled(False)
# 当前主题Q3DTheme设置字体
self.m_graph.activeTheme().setFont(
QFont('Times New Roman', self.m_fontSize))
# 当前主题Q3DTheme设置标签是使用彩色背景还是使用完全透明的背景绘制
self.m_graph.activeTheme().setLabelBackgroundEnabled(True)
# 是否按比例将比例尺设置为单个系列比例尺来缩放比例
self.m_graph.setMultiSeriesUniform(True)
self.m_temperatureAxis.setTitle(
Tr.get("Average temperature", "Average temperature"))
# 轴上的段数。这表明绘制了多少标签。要绘制的网格线的数量使用公式计算：segments * subsegments + 1。预设默认值为5。该值不能低于1
self.m_temperatureAxis.setSegmentCount(self.m_segments)
# 轴上每个段内的子段数。
# 除每个线段外，还在每个子线段之间绘制网格线。预设默认值为1。该值不能低于1。
self.m_temperatureAxis.setSubSegmentCount(self.m_subSegments)
self.m_temperatureAxis.setRange(self.m_minval, self.m_maxval)
self.m_temperatureAxis.setLabelFormat(u"%.1f \N{degree sign}C")
self.m_yearAxis.setTitle("Year")
self.m_monthAxis.setTitle("Month")
self.m_graph.setValueAxis(self.m_temperatureAxis)
# 设置活动行的轴为年份
self.m_graph.setRowAxis(self.m_yearAxis)
# 设置活动列的轴为月份
self.m_graph.setColumnAxis(self.m_monthAxis)
self.m_primarySeries.setItemLabelFormat(
"Oulu - @colLabel @rowLabel: @valueLabel")
# 设置网格类型
self.m_primarySeries.setMesh(QAbstract3DSeries.MeshBevelBar)
self.m_primarySeries.setMeshSmooth(False)
self.m_secondarySeries.setItemLabelFormat(
"Helsinki - @colLabel @rowLabel: @valueLabel")
self.m_secondarySeries.setMesh(QAbstract3DSeries.MeshBevelBar)
self.m_secondarySeries.setMeshSmooth(False)
self.m_secondarySeries.setVisible(False)
self.m_graph.addSeries(self.m_primarySeries)
self.m_graph.addSeries(self.m_secondarySeries)
self.m_preset = Q3DCamera.CameraPresetFront
self.changePresetCamera()
self.resetTemperatureData()
def setupWindow(self):
"""The window is comprised of two main parts: A Q3DBars graph on the left, and QToolBox
on the right containing different widgets for tweaking different settings in the Q3DBars graph."""
header_label = QLabel(
"Comparison of Average Monthly Temperatures of Select U.S. Cities 1990-2000 (˚C)"
)
header_label.setAlignment(Qt.AlignCenter)
# Load and prepare the data for the three datasets
data_files = [
"LasVegas_temp.csv", "Spokane_temp.csv", "Richmond_temp.csv"
]
temperature_data = {}
# Create a dictionary with key, value pairs pertaining to each city and dataset
for f in data_files:
data_name = f.split(
"_")[0] + "_data" # Create a dictionary key for each city
data = self.loadCSVFile("files/" + f)
# Select 11 years: 1990-2000; the first column in each file is the years
rows, columns = data.shape
self.years = data[:, 0]
monthly_temps = data[:, 1:columns].astype(float)
temperature_data[data_name] = monthly_temps
bar_graph = Q3DBars() # Create instance for bar graph
bar_graph.setMultiSeriesUniform(
True) # Bars are scaled proportionately
bar_graph.scene().activeCamera().setCameraPreset(
Q3DCamera.CameraPresetFront)
# Create lists of QBarDataItem objects for each city
vegas_data_items = []
for row in temperature_data["LasVegas_data"]:
vegas_data_items.append([QBarDataItem(value) for value in row])
spokane_data_items = []
for row in temperature_data["Spokane_data"]:
spokane_data_items.append([QBarDataItem(value) for value in row])
richmond_data_items = []
for row in temperature_data["Richmond_data"]:
richmond_data_items.append([QBarDataItem(value) for value in row])
self.months = [
"January", "February", "March", "April", "May", "June", "July",
"August", "September", "October", "November", "December"
]
# Create instances of QBar3DSeries for each set of data; dataProxy() handles
# modifying data in the series
vegas_series = QBar3DSeries()
vegas_series.dataProxy().addRows(vegas_data_items)
vegas_series.dataProxy().setRowLabels(self.years) # rowLabel
vegas_series.dataProxy().setColumnLabels(self.months) # colLabel
spokane_series = QBar3DSeries()
spokane_series.dataProxy().addRows(spokane_data_items)
richmond_series = QBar3DSeries()
richmond_series.dataProxy().addRows(richmond_data_items)
# Create the valueLabel
temperature_axis = QValue3DAxis()
temperature_axis.setRange(-10, 40)
temperature_axis.setLabelFormat(u"%.1f \N{degree sign}C")
bar_graph.setValueAxis(temperature_axis)
# Set the format for the labels that appear when items are clicked on
vegas_series.setItemLabelFormat(
"LasVegas - @colLabel @rowLabel: @valueLabel")
spokane_series.setItemLabelFormat(
"Spokane - @colLabel @rowLabel: @valueLabel")
richmond_series.setItemLabelFormat(
"Richmond - @colLabel @rowLabel: @valueLabel")
# Add the three series to the bar graph
bar_graph.setPrimarySeries(vegas_series)
bar_graph.addSeries(spokane_series)
bar_graph.addSeries(richmond_series)
# Create a QWidget to hold only the graph
graph_container = QWidget.createWindowContainer(bar_graph)
main_h_box = QHBoxLayout() # Main layout for the entire window
graph_v_box = QVBoxLayout() # Layout that holds the graph
graph_v_box.addWidget(header_label)
graph_v_box.addWidget(graph_container, 1)
##############################################################################
# The following section creates the QToolBox that appears on the
# right of the window and contains widgets for interacting with the graph
self.modifier = GraphModifier(self,
bar_graph) # Create modifier instance
settings_toolbox = QToolBox()
settings_toolbox.setFixedWidth(300)
settings_toolbox.setCurrentIndex(0) # Show the first tab
# The first tab - Widgets for rotating the bar graph and changing the camera
horizontal_rotation_slider = QSlider(Qt.Horizontal)
horizontal_rotation_slider.setTickInterval(20)
horizontal_rotation_slider.setRange(-180, 180)
horizontal_rotation_slider.setValue(0)
horizontal_rotation_slider.setTickPosition(QSlider.TicksBelow)
horizontal_rotation_slider.valueChanged.connect(
self.modifier.rotateHorizontal)
vertical_rotation_slider = QSlider(Qt.Horizontal)
vertical_rotation_slider.setTickInterval(20)
vertical_rotation_slider.setRange(-180, 180)
vertical_rotation_slider.setValue(0)
vertical_rotation_slider.setTickPosition(QSlider.TicksBelow)
vertical_rotation_slider.valueChanged.connect(
self.modifier.rotateVertical)
# QPushButton for changing the camera's view point
camera_view_button = QPushButton("Change Camera View")
camera_view_button.clicked.connect(self.modifier.changeCameraView)
# Layout for the View tab (first tab)
view_tab_container = QWidget()
view_tab_v_box = QVBoxLayout()
view_tab_v_box.setAlignment(Qt.AlignTop)
view_tab_v_box.addWidget(QLabel("Rotate Horizontally"))
view_tab_v_box.addWidget(horizontal_rotation_slider)
view_tab_v_box.addWidget(QLabel("Rotate Vertically"))
view_tab_v_box.addWidget(vertical_rotation_slider)
view_tab_v_box.addWidget(camera_view_button)
view_tab_container.setLayout(view_tab_v_box)
settings_toolbox.addItem(view_tab_container, "View")
# The second tab - Widgets for changing the appearance of the graph. Recheck the
# background and grid checkboxes if the theme has changed
show_background_cb = QCheckBox("Show Background")
show_background_cb.setChecked(True)
show_background_cb.stateChanged.connect(
self.modifier.showOrHideBackground)
self.modifier.background_selected.connect(
show_background_cb.setChecked)
show_grid_cb = QCheckBox("Show Grid")
show_grid_cb.setChecked(True)
show_grid_cb.stateChanged.connect(self.modifier.showOrHideGrid)
self.modifier.grid_selected.connect(show_grid_cb.setChecked)
smooth_bars_cb = QCheckBox("Smoothen Bars")
smooth_bars_cb.stateChanged.connect(self.modifier.smoothenBars)
# QComboBox for selecting the Qt theme
themes = [
"Qt", "Primary Colors", "Digia", "Stone Moss", "Army Blue",
"Retro", "Ebony", "Isabelle"
]
select_theme_combo = QComboBox()
select_theme_combo.addItems(themes)
select_theme_combo.setCurrentIndex(0)
select_theme_combo.currentIndexChanged.connect(
self.modifier.changeTheme)
# QComboBox for selecting the visual style of the bars
bar_style_combo = QComboBox()
bar_style_combo.addItem("Bar", QAbstract3DSeries.MeshBar)
bar_style_combo.addItem("Pyramid", QAbstract3DSeries.MeshPyramid)
bar_style_combo.addItem("Cylinder", QAbstract3DSeries.MeshCylinder)
bar_style_combo.addItem("Sphere", QAbstract3DSeries.MeshSphere)
bar_style_combo.setCurrentIndex(0)
bar_style_combo.currentIndexChanged.connect(
self.modifier.changeBarStyle)
# Layout for the Style tab (second tab)
style_tab_container = QWidget()
style_tab_v_box = QVBoxLayout()
style_tab_v_box.setAlignment(Qt.AlignTop)
style_tab_v_box.addWidget(show_background_cb)
style_tab_v_box.addWidget(show_grid_cb)
style_tab_v_box.addWidget(smooth_bars_cb)
style_tab_v_box.addWidget(QLabel("Select Qt Theme"))
style_tab_v_box.addWidget(select_theme_combo)
style_tab_v_box.addWidget(QLabel("Select Bar Style"))
style_tab_v_box.addWidget(bar_style_combo)
style_tab_container.setLayout(style_tab_v_box)
settings_toolbox.addItem(style_tab_container, "Style")
# The third tab - Widgets for hiding/showing different series and changing how
# items are viewed and selected
second_series_cb = QCheckBox("Show Second Series")
second_series_cb.setChecked(True)
second_series_cb.stateChanged.connect(self.modifier.showOrHideSeries)
third_series_cb = QCheckBox("Show Third Series")
third_series_cb.setChecked(True)
third_series_cb.stateChanged.connect(self.modifier.showOrHideSeries)
# QComboBox for changing how items in the bar graph are selected
selection_mode_combo = QComboBox()
selection_mode_combo.addItem("None", QAbstract3DGraph.SelectionNone)
selection_mode_combo.addItem("Bar", QAbstract3DGraph.SelectionItem)
selection_mode_combo.addItem("Row", QAbstract3DGraph.SelectionRow)
selection_mode_combo.addItem("Column",
QAbstract3DGraph.SelectionColumn)
selection_mode_combo.addItem(
"Item, Row, Column", QAbstract3DGraph.SelectionItemRowAndColumn)
selection_mode_combo.setCurrentIndex(1)
selection_mode_combo.currentIndexChanged.connect(
self.modifier.changeSelectionStyle)
# QComboBox for selecting which years to view
select_year_combo = QComboBox()
select_year_combo.addItems(self.years)
select_year_combo.addItem("All Years")
select_year_combo.setCurrentIndex(len(self.years))
select_year_combo.currentIndexChanged.connect(
self.modifier.selectYears)
# QComboBox for selecting which months to view
select_month_combo = QComboBox()
select_month_combo.addItems(self.months)
select_month_combo.addItem("All Months")
select_month_combo.setCurrentIndex(len(self.months))
select_month_combo.currentIndexChanged.connect(
self.modifier.selectMonths)
# Layout for the Selection tab (third tab)
selection_tab_container = QWidget()
selection_tab_v_box = QVBoxLayout()
selection_tab_v_box.addWidget(second_series_cb)
selection_tab_v_box.addWidget(third_series_cb)
selection_tab_v_box.addWidget(QLabel("Choose Selection Mode"))
selection_tab_v_box.addWidget(selection_mode_combo)
selection_tab_v_box.addWidget(QLabel("Select Year"))
selection_tab_v_box.addWidget(select_year_combo)
selection_tab_v_box.addWidget(QLabel("Select Month"))
selection_tab_v_box.addWidget(select_month_combo)
selection_tab_container.setLayout(selection_tab_v_box)
settings_toolbox.addItem(selection_tab_container, "Selection")
# Set up the layout for the settings toolbox
settings_v_box = QVBoxLayout()
settings_v_box.addWidget(settings_toolbox, 0, Qt.AlignTop)
main_h_box.addLayout(graph_v_box)
main_h_box.addLayout(settings_v_box)
main_widget = QWidget()
main_widget.setLayout(main_h_box)
self.setCentralWidget(main_widget)