matplotlib-devel Mailing List for matplotlib

Not sure what you mean about agg + py3k, it should work fine (as we test
it).
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

SpanSelector is a powerful widget that allows to define a particular
region in a Figure. Some time ago I switched to python3 and needed to
use gtk3cairo instead of gtkagg; to my knowledge there is still a
message preventing using agg backend with python3. Unfortunately since
then I am not able to use SpanSelector widget with gtk3cairo. For
instance with the example [1], an error message appears:
 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'
This using version 1.4.2 of matplotlib.
Does exists a way to have SpanSelector operating with gtk3cairo
backend ? I tried to look down to the code of gtkagg but it refers to
the C implementation of the library (_RendererAgg), is there an
equivalent in Cairo ?
Arnaud.
[1] http://matplotlib.org/examples/widgets/span_selector.html