NavigationToolbar2GTK not working on hand made subplot instance

Hi John and list,

Sorry to take your time.

from matplotlib.backends.backend_gtkagg import FigureCanvasGTKAgg as FigureCanvas
from matplotlib.backends.backend_gtkagg import NavigationToolbar2GTKAgg as NavigationToolbar

when i do:

    >fig = Figure(figsize=(5,4), dpi=100)|||
    >ax = fig.add_subplot(111) # 1|
    >t = arange(0.0,3.0,0.01)|
    >s = sin(2*pi*t)|
    >ax.plot(t,s)|||||
    >canvas = FigureCanvas(fig)|
    >vbox.pack_start(canvas)|
    >toolbar = NavigationToolbar(canvas, win)|
    >vbox.pack_start(toolbar, False, False)
    >

I can zoom on the figure and it is redrawn.

My problem is i need to create a subplot instance myself:

    >fig = Figure(figsize=(5,4), dpi=100)
    ax = Subplot(fig,111) || # 1||
    t = arange(0.0,3.0,0.01)
    s = sin(2*pi*t)
    ax.plot(t,s)
    fig.add_subplot(ax) ||# 2 -> To display the hand
    subplot in the figure.|
    >canvas = FigureCanvas(fig)
    vbox.pack_start(canvas)
    toolbar = NavigationToolbar(canvas, win)
    vbox.pack_start(toolbar, False, False)|

The application is crashing. GTK seems to fail displaying the canvas.

Is it a bug or am i doing something wrong?

Thanks a lot for the answer,
Regards,
Philippe Collet