@@ -90,6 +90,22 @@ def ignore(self, event):
9090 """
9191return not self .active
9292
93+ def _changed_canvas (self ):
94+ """
95+ Someone has switched the canvas on us!
96+
97+ This happens if `savefig` needs to save to a format the previous
98+ backend did not support (e.g. saving a figure using an Agg based
99+ backend saved to a vector format).
100+
101+ Returns
102+ -------
103+ bool
104+ True if the canvas has been changed.
105+
106+ """
107+ return self .canvas is not self .ax .figure .canvas
108+
93109
94110class AxesWidget (Widget ):
95111"""
@@ -1088,7 +1104,7 @@ def __init__(self, ax, labels, actives=None, *, useblit=True,
10881104
10891105def _clear (self ,event ):
10901106"""Internal event handler to clear the buttons."""
1091- if self .ignore (event )or self .canvas is not self . ax . figure . canvas :
1107+ if self .ignore (event )or self ._changed_canvas () :
10921108return
10931109self ._background = self .canvas .copy_from_bbox (self .ax .bbox )
10941110self .ax .draw_artist (self ._checks )
@@ -1700,7 +1716,7 @@ def __init__(self, ax, labels, active=0, activecolor=None, *,
17001716
17011717def _clear (self ,event ):
17021718"""Internal event handler to clear the buttons."""
1703- if self .ignore (event )or self .canvas is not self . ax . figure . canvas :
1719+ if self .ignore (event )or self ._changed_canvas () :
17041720return
17051721self ._background = self .canvas .copy_from_bbox (self .ax .bbox )
17061722self .ax .draw_artist (self ._buttons )
@@ -1971,7 +1987,7 @@ def __init__(self, ax, horizOn=True, vertOn=True, useblit=False,
19711987
19721988def clear (self ,event ):
19731989"""Internal event handler to clear the cursor."""
1974- if self .ignore (event )or self .canvas is not self . ax . figure . canvas :
1990+ if self .ignore (event )or self ._changed_canvas () :
19751991return
19761992if self .useblit :
19771993self .background = self .canvas .copy_from_bbox (self .ax .bbox )