Source code for enaml.qt.qt_mpl_canvas

#  Copyright (c) 2012, Enthought, Inc.
#  All rights reserved.
# Special thanks to Steven Silvester for contributing this module!
from .qt.QtCore import Qt
from .qt.QtGui import QFrame, QVBoxLayout
from .qt_constraints_widget import size_hint_guard
from .qt_control import QtControl

from matplotlib.backends.backend_qt4agg import FigureCanvasQTAgg
from matplotlib.backends.backend_qt4agg import NavigationToolbar2QTAgg

[docs]class QtMPLCanvas(QtControl): """ A Qt implementation of an Enaml MPLCanvas. """ #: Internal storage for the matplotlib figure. _figure = None #: Internal storage for whether or not to show the toolbar. _toolbar_visible = False #-------------------------------------------------------------------------- # Setup Methods #--------------------------------------------------------------------------
[docs] def create_widget(self, parent, tree): """ Create the underlying widget. """ widget = QFrame(parent) layout = QVBoxLayout() layout.setContentsMargins(0, 0, 0, 0) layout.setSpacing(0) widget.setLayout(layout) return widget
[docs] def create(self, tree): """ Create and initialize the underlying widget. """ super(QtMPLCanvas, self).create(tree) self._figure = tree['figure'] self._toolbar_visible = tree['toolbar_visible']
[docs] def init_layout(self): """ Initialize the layout of the underlying widget. """ super(QtMPLCanvas, self).init_layout() self.refresh_mpl_widget() #-------------------------------------------------------------------------- # Message Handlers #--------------------------------------------------------------------------
[docs] def on_action_set_figure(self, content): """ Handle the 'set_figure' action from the Enaml widget. """ self._figure = content['figure'] with size_hint_guard(self): self.refresh_mpl_widget()
[docs] def on_action_set_toolbar_visible(self, content): """ Handle the 'set_toolbar_visible' action from the Enaml widget. """ visible = content['toolbar_visible'] self._toolbar_visible = visible layout = self.widget().layout() if layout.count() == 2: with size_hint_guard(self): toolbar = layout.itemAt(0).widget() toolbar.setVisible(visible) #-------------------------------------------------------------------------- # Widget Update Methods #--------------------------------------------------------------------------
[docs] def refresh_mpl_widget(self): """ Create the mpl widget and update the underlying control. """ # Delete the old widgets in the layout, it's just shenanigans # to try to reuse the old widgets when the figure changes. widget = self.widget() layout = widget.layout() while layout.count(): layout_item = layout.takeAt(0) layout_item.widget().deleteLater() # Create the new figure and toolbar widgets. It seems that key # events will not be processed without an mpl figure manager. # However, a figure manager will create a new toplevel window, # which is certainly not desired in this case. This appears to # be a limitation of matplotlib. The canvas is manually set to # visible, or QVBoxLayout will ignore it for size hinting. figure = self._figure if figure is not None: canvas = FigureCanvasQTAgg(figure) canvas.setParent(widget) canvas.setFocusPolicy(Qt.ClickFocus) canvas.setVisible(True) toolbar = NavigationToolbar2QTAgg(canvas, widget) toolbar.setVisible(self._toolbar_visible) layout.addWidget(toolbar) layout.addWidget(canvas)