[Matplotlib-users] help with colorbar

Hello everyone, 

I have a problem with a colorbar:
I have a stackedbar and a colorbar that I want to create or delete by clicking 
on a button.. but when the colorbar is deleted I want to change the dimension 
of the axes, resizing it even in the place occupied by the colorbar..
I need to create the colorbar by using the function "make_axes_locatable" and 
not others function..

Someone can help me?

this is the code: 

from matplotlib.figure import Figure
from mpl_toolkits.axes_grid.axes_divider import make_axes_locatable
from matplotlib import mpl, colorbar
from matplotlib.backends.backend_qt4agg import FigureCanvasQTAgg as 
FigureCanvas
from PyQt4.QtCore import *
from PyQt4.QtGui import *


import sys

class Test(QWidget):
    def __init__(self):
        QWidget.__init__(self)
        self.resize(1000, 700)
        self.setGeometry(20,30,700,500)       
        self.fig = Figure(figsize=(100,100), dpi=75)         
        self.canvas = FigureCanvas(self.fig)
        self.axes = self.fig.add_subplot(111)
        b = self.axes.bar([0,1,2,3],[5,4,9,6])
        self.colorbar = True
        self.Colorbar()
        self.old_size = self.axes.get_position()
        self.btn = QPushButton()
        self.btn.resize(20,20)
        self.btn.clicked.connect(self.OnBtnClicked)
        self.Layout = QHBoxLayout()
        spacerItem = QSpacerItem(40, 20, QSizePolicy.Expanding, 
                                 QSizePolicy.Minimum)
        self.Layout.addItem(spacerItem)
        self.Layout.addWidget(self.canvas)
        self.Layout.addWidget(self.btn)
        self.setLayout(self.Layout)

    def OnBtnClicked(self):
        self.colorbar = not self.colorbar
        self.Colorbar()

    def Colorbar(self):
        if self.colorbar :
            self.divider = make_axes_locatable(self.axes)
            self.cax = self.divider.append_axes("right", size="3%", pad=0.1)
            self.cmap = mpl.colors.ListedColormap(['b'])            
            self.cb = mpl.colorbar.ColorbarBase(self.cax, 
                                                cmap=self.cmap, 
                                                orientation='vertical') 
        else:
            if hasattr(self, "cb") :
                fig = self.axes.get_figure()
                fig.delaxes(self.cb.ax)
                del self.cb
                self.axes.set_position(self.old_size)  
        self.fig.canvas.draw()



app = QApplication(sys.argv)
win = Test()
win.show()
sys.exit(app.exec_())


thanks
Erika