python - 向图中添加导航工具栏(matplotlib和PyQt4)

我想在我的PyQt4 GUI中创建一个导航工具栏，但是我不能让它工作，我必须承认我大部分是复制粘贴的代码，我并没有真正得到它。如果你能告诉我如何添加导航工具栏并解释它是如何生成的，那就太好了。提前谢谢你。
顺便说一句，我见过This Post但我相信它和我的不同，我不知道如何使用它。

from PyQt4 import QtGui
from matplotlib.backends.backend_qt4agg import FigureCanvasQTAgg as FigureCanvas

from matplotlib.figure import Figure

class MplCanvas(FigureCanvas):

    def __init__( self ):
        self.fig = Figure()
        self.ax = self.fig.add_subplot( 111 )

        FigureCanvas.__init__( self, self.fig )
        FigureCanvas.setSizePolicy( self, QtGui.QSizePolicy.Expanding,QtGui.QSizePolicy.Expanding )
        FigureCanvas.updateGeometry( self )


class matplotlibWidget(QtGui.QWidget):

    def __init__( self, parent = None ):
        QtGui.QWidget.__init__( self, parent )
        self.canvas = MplCanvas()
        #self.toolbar = self.canvas.toolbar #Dunno How :(

        self.vbl = QtGui.QVBoxLayout()
        self.vbl.addWidget( self.canvas )
        self.setLayout( self.vbl )

最佳答案

我设法解决了这个问题，代码应该是这样的

from PyQt4 import QtGui
from matplotlib.backends.backend_qt4agg import FigureCanvasQTAgg as FigureCanvas
from matplotlib.backends.backend_qt4 import NavigationToolbar2QT as NavigationToolbar
from matplotlib.figure import Figure

class MplCanvas(FigureCanvas):

    def __init__( self ):
        self.fig = Figure()
        self.ax = self.fig.add_subplot( 111 )

        FigureCanvas.__init__( self, self.fig )
        FigureCanvas.setSizePolicy( self, QtGui.QSizePolicy.Expanding,QtGui.QSizePolicy.Expanding )
        FigureCanvas.updateGeometry( self )


class matplotlibWidget(QtGui.QWidget):

    def __init__( self, parent = None ):
        QtGui.QWidget.__init__( self, parent )
        self.canvas = MplCanvas() #create canvas that will hold our plot
        self.navi_toolbar = NavigationToolbar(self.canvas, self) #createa navigation toolbar for our plot canvas

        self.vbl = QtGui.QVBoxLayout()
        self.vbl.addWidget( self.canvas )
        self.vbl.addWidget(self.navi_toolbar)
        self.setLayout( self.vbl )