Re: [matplotlib-devel] SaveFig bug in TkAgg backend

[Mark B. <ma...@gm...>]

This is a well known problem, reported about a year or so ago.
John Hunter tried to get some help on the (TK?) mailinglist, but I
don't think anybody responded. I looked into it too, but couldn't find
a solution (that doesn't mean much, except for that it is not
blatently obvious).
It would be great if somebody would know how to fix this.
Strangely enough I have written a GUI myself where I use the toolbar,
and the save button works fine there.
Mark

> Date: Thu, 10 May 2007 13:31:18 -0600
> From: "Urvashi R.V." <urv...@gm...>
>
> Hi,
>
> When the "save" button is used on the matplotlib tkagg toolbar, it
> uses the "Tk"  "asksavefilename" object from the "tkFileDialog" class,
> to pop up a little window that allows you to select the name and type
> of file to save.    This function internally calls "figure.destroy()".
> and the currently active figure gets destroyed (but it is still visible
> and memory is not freed). The next plot then creates a new figure
> window with the same figure._num as the previous.
>
> see...
> backend_tkagg.py : line 621
> -> class NavigationToolbar2TkAgg ::   def save_figure(...)
> (callback for the toolbar.bsave button)
>
> The "asksavefilename" function call, triggers Gcf.destroy().  This can
> be seen by placing a print statement in
> _pylab_helpers.py : line 16
> -> class Gcf :: def destroy(num)