[Matplotlib-users] change ylim xlim from canvas doesn't work

Hi,

when I try to change the ylim and xlim directly from the displayed canvas i
get this error(when  I change them in the code I have no problems):

Traceback (most recent call last):
  File "C:\Anaconda\lib\site-packages\matplotlib\backends\backend_qt4.py",
line
594, in edit_parameters
    figureoptions.figure_edit(axes, self)
  File
"C:\Anaconda\lib\site-packages\matplotlib\backends\qt4_editor\figureoptio
ns.py", line 134, in figure_edit
    icon=get_icon('qt4_editor_options.svg'), apply=apply_callback)
  File
"C:\Anaconda\lib\site-packages\matplotlib\backends\qt4_editor\formlayout.py",
line 544, in fedit
    dialog = FormDialog(data, title, comment, icon, parent, apply)
  File
"C:\Anaconda\lib\site-packages\matplotlib\backends\qt4_editor\formlayout.py",
line 461, in __init__
    self.formwidget.setup()
  File
"C:\Anaconda\lib\site-packages\matplotlib\backends\qt4_editor\formlayout.py",
line 433, in setup
    widget.setup()
  File
"C:\Anaconda\lib\site-packages\matplotlib\backends\qt4_editor\formlayout.py",
line 408, in setup
    widget.setup()
  File
"C:\Anaconda\lib\site-packages\matplotlib\backends\qt4_editor\formlayout.py",
line 302, in setup
    field = ColorLayout(QColor(value), self)
TypeError: QVariant must be holding a QColor

my code is:
fig = plt.figure()
figf = plt.figure()

for el in sequence:
        #some operations
        ax = fig.add_subplot(111)

        img = ax.plot(xflo, yflo, label=etich, marker = '.')
        ax.set_yscale('log')
        ax.set_xscale('log')
        ax.legend(bbox_to_anchor=(1.05, 1), loc=4, borderaxespad=0.)
        fig.canvas.draw()
        ax1 = figf.add_subplot(111)

        img1 = ax1.plot(logx, logy, label=etich)#, marker = style)
        ax1.legend(bbox_to_anchor=(1.05, 1), loc=4, borderaxespad=0.)

        figf.canvas.draw()

thanks

Gabriele