qtmpl.py

from PyQt4.QtCore import *
from PyQt4.QtGui import *

from matplotlib.backends.backend_qt4agg import FigureCanvasQTAgg as FigureCanvas
from matplotlib.backends.backend_qt4agg import NavigationToolbar2QTAgg as NavigationToolbar
from matplotlib.figure import Figure

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)
        # We want the axes cleared every time plot() is called
        self.axes.hold(False)
        self.canvas = FigureCanvas(fig)
        self.canvas.setParent(parent)

        self.canvas.setSizePolicy(QSizePolicy.Expanding,
                                   QSizePolicy.Expanding)
        self.mpl_toolbar = NavigationToolbar(self.canvas, parent)        
        self.canvas.updateGeometry()