.. _user_interfaces-embedding_in_qt4:

user_interfaces example code: embedding_in_qt4.py
=================================================

[`source code <embedding_in_qt4.py>`_]

::

    
    # embedding_in_qt4.py --- Simple Qt4 application embedding matplotlib canvases
    #
    # Copyright (C) 2005 Florent Rougon
    #               2006 Darren Dale
    #
    # This file is an example program for matplotlib. It may be used and
    # modified with no restriction; raw copies as well as modified versions
    # may be distributed without limitation.
    
    from __future__ import unicode_literals
    import sys
    import os
    import random
    from matplotlib.backends import qt_compat
    use_pyside = qt_compat.QT_API == qt_compat.QT_API_PYSIDE
    if use_pyside:
        from PySide import QtGui, QtCore
    else:
        from PyQt4 import QtGui, QtCore
    
    from numpy import arange, sin, pi
    from matplotlib.backends.backend_qt4agg import FigureCanvasQTAgg as FigureCanvas
    from matplotlib.figure import Figure
    
    progname = os.path.basename(sys.argv[0])
    progversion = "0.1"
    
    
    class MyMplCanvas(FigureCanvas):
        """Ultimately, this is a QWidget (as well as a FigureCanvasAgg, etc.)."""
    
        def __init__(self, parent=None, width=5, height=4, dpi=100):
            fig = Figure(figsize=(width, height), dpi=dpi)
            self.axes = fig.add_subplot(111)
    
            self.compute_initial_figure()
    
            FigureCanvas.__init__(self, fig)
            self.setParent(parent)
    
            FigureCanvas.setSizePolicy(self,
                                       QtGui.QSizePolicy.Expanding,
                                       QtGui.QSizePolicy.Expanding)
            FigureCanvas.updateGeometry(self)
    
        def compute_initial_figure(self):
            pass
    
    
    class MyStaticMplCanvas(MyMplCanvas):
        """Simple canvas with a sine plot."""
    
        def compute_initial_figure(self):
            t = arange(0.0, 3.0, 0.01)
            s = sin(2*pi*t)
            self.axes.plot(t, s)
    
    
    class MyDynamicMplCanvas(MyMplCanvas):
        """A canvas that updates itself every second with a new plot."""
    
        def __init__(self, *args, **kwargs):
            MyMplCanvas.__init__(self, *args, **kwargs)
            timer = QtCore.QTimer(self)
            timer.timeout.connect(self.update_figure)
            timer.start(1000)
    
        def compute_initial_figure(self):
            self.axes.plot([0, 1, 2, 3], [1, 2, 0, 4], 'r')
    
        def update_figure(self):
            # Build a list of 4 random integers between 0 and 10 (both inclusive)
            l = [random.randint(0, 10) for i in range(4)]
            self.axes.cla()
            self.axes.plot([0, 1, 2, 3], l, 'r')
            self.draw()
    
    
    class ApplicationWindow(QtGui.QMainWindow):
        def __init__(self):
            QtGui.QMainWindow.__init__(self)
            self.setAttribute(QtCore.Qt.WA_DeleteOnClose)
            self.setWindowTitle("application main window")
    
            self.file_menu = QtGui.QMenu('&File', self)
            self.file_menu.addAction('&Quit', self.fileQuit,
                                     QtCore.Qt.CTRL + QtCore.Qt.Key_Q)
            self.menuBar().addMenu(self.file_menu)
    
            self.help_menu = QtGui.QMenu('&Help', self)
            self.menuBar().addSeparator()
            self.menuBar().addMenu(self.help_menu)
    
            self.help_menu.addAction('&About', self.about)
    
            self.main_widget = QtGui.QWidget(self)
    
            l = QtGui.QVBoxLayout(self.main_widget)
            sc = MyStaticMplCanvas(self.main_widget, width=5, height=4, dpi=100)
            dc = MyDynamicMplCanvas(self.main_widget, width=5, height=4, dpi=100)
            l.addWidget(sc)
            l.addWidget(dc)
    
            self.main_widget.setFocus()
            self.setCentralWidget(self.main_widget)
    
            self.statusBar().showMessage("All hail matplotlib!", 2000)
    
        def fileQuit(self):
            self.close()
    
        def closeEvent(self, ce):
            self.fileQuit()
    
        def about(self):
            QtGui.QMessageBox.about(self, "About",
                                    """embedding_in_qt4.py example
    Copyright 2005 Florent Rougon, 2006 Darren Dale
    
    This program is a simple example of a Qt4 application embedding matplotlib
    canvases.
    
    It may be used and modified with no restriction; raw copies as well as
    modified versions may be distributed without limitation."""
                                    )
    
    
    qApp = QtGui.QApplication(sys.argv)
    
    aw = ApplicationWindow()
    aw.setWindowTitle("%s" % progname)
    aw.show()
    sys.exit(qApp.exec_())
    #qApp.exec_()
    

Keywords: python, matplotlib, pylab, example, codex (see :ref:`how-to-search-examples`)