Re: [matplotlib-devel] SpanSelector with gtk3cairo backend

[Arnaud G. <ar...@os...>]

Le mardi 11 novembre 2014 à 08:56 +0000, Jens Nielsen a écrit :
> There was an issue with the GTK3Agg backend on Python 3 due to a
> missing feature in the python 3 port of PyCairo but this has been
> fixed in Matplotlib 1.4.0 by making it possible to use cairocffi as an
> alternative to PyCairo.
This is exactly the issue I meant.

(...)

> On Mon, Nov 10, 2014 at 11:26 PM, Thomas Caswell <tca...@gm...>
> wrote:
(...) 
>         The issue is that the cairo backend is a vector backend, which
>         does not have a notion of blitting, which is something that
>         span selector uses to make it nice and snappy.  Should be able
>         to get it to work by passing the kwarg `useblit=False` to the
>         constructor.
>         
>         Tom

In fact I stupidly copied the example [1], missing completely this
argument in the constructor. Setting useblit=False makes it working
nicely. Thanks.

Arnaud.

[1] http://matplotlib.org/examples/widgets/span_selector.html

PS: For the records, here is the full message that appears when setting
useblit=True in [1] and matplotlibrc contains "backend : GTK3Cairo",
matplotlib version 1.4.2 (debian):

$ ./testspan.py
Traceback (most recent call last):
  File
"/usr/lib/python3/dist-packages/matplotlib/backends/backend_gtk3cairo.py", line 45, in on_draw_event
    self._render_figure(w, h)
  File
"/usr/lib/python3/dist-packages/matplotlib/backends/backend_gtk3cairo.py", line 34, in _render_figure
    self.figure.draw (self._renderer)
  File "/usr/lib/python3/dist-packages/matplotlib/artist.py", line 59,
in draw_wrapper
    draw(artist, renderer, *args, **kwargs)
  File "/usr/lib/python3/dist-packages/matplotlib/figure.py", line 1085,
in draw
    self.canvas.draw_event(renderer)
  File "/usr/lib/python3/dist-packages/matplotlib/backend_bases.py",
line 1778, in draw_event
    self.callbacks.process(s, event)
  File "/usr/lib/python3/dist-packages/matplotlib/cbook.py", line 540,
in process
    proxy(*args, **kwargs)
  File "/usr/lib/python3/dist-packages/matplotlib/cbook.py", line 415,
in __call__
    return mtd(*args, **kwargs)
  File "/usr/lib/python3/dist-packages/matplotlib/widgets.py", line
1197, in update_background
    self.background = self.canvas.copy_from_bbox(self.ax.bbox)
AttributeError: 'FigureCanvasGTK3Cairo' object has no attribute
'copy_from_bbox'