[Bug]: PolygonSelector should hide itself when zoom/pan is active

[anntzer]

Bug summary

When interactive zoom/pan is active, widgets.PolygonSelector correctly disables itself (i.e. clicking and dragging zooms or pans the axes without creating a selection), but the selector cursor (a big circular marker) stays drawn at its last position (prior to zoom/pan being turned on). It should instead be hidden.

Code for reproduction

from pylab import *
ls = mpl.widgets.PolygonSelector(gca(), print)
# Move the cursor around, then toggle zoom pan via the toolbar
# or by pressing "o"/"p"

Actual outcome

The PolygonSelector cursor stays drawn at an incorrect position.

Expected outcome

The cursor is temporarily hidden.

Additional information

Probably a good first issue? I suspect the fix is along the lines of

diff --git i/lib/matplotlib/widgets.py w/lib/matplotlib/widgets.py
index eaa35e2544..4cd48ab3c1 100644
--- i/lib/matplotlib/widgets.py
+++ w/lib/matplotlib/widgets.py
@@ -4000,11 +4000,15 @@ class PolygonSelector(_SelectorWidget):
         # needs to process the move callback even if there is no button press.
         # _SelectorWidget.onmove include logic to ignore move event if
         # _eventpress is None.
-        if not self.ignore(event):
+        if self.ignore(event):
+            if not self.canvas.widgetlock.available(self) and self._xys:
+                self._xys[-1] = (np.nan, np.nan)
+                self._draw_polygon()
+            return False
+        else:
             event = self._clean_event(event)
             self._onmove(event)
             return True
-        return False
 
     def _onmove(self, event):
         """Cursor move event handler."""

i.e. if something else is active, just hide the last point of the polygon. However this patch doesn't handle interaction with the various extra widget states (moving, etc.); likely it should only apply in the "position pending" mode (last else block of _onmove).

Operating system

No response

Matplotlib Version

3.10.0.dev125+g63156f2ca6

Matplotlib Backend

qtagg

Python version

3.12

Jupyter version

no

Installation

git checkout

[github-actions]

Good first issue - notes for new contributors

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[Kaustbh]

Hi there! I'm new to open source, but I'm eager to dive in and help out. I came across this issue and I think I can tackle it, can I work on it ?

[ksunden]

Hi @Kaustbh,

We do not assign any issues, and anybody is free to work on anything. In general, we tend to give preference to the first person to open a PR (absent a clear technical reason to opt for a newer PR).

In this case, there are no PRs yet for this issue.

See also https://matplotlib.org/devdocs/devel/contribute.html#work-on-an-issue

[Kaustbh]

@anntzer , I tried to reproduce the issue , can you tell what is the problem . (backend = WebAgg) ,

demo.mp4

[Kaustbh]

@anntzer please reply .

[anntzer]

Your movie doesn't play, and as noted in the report this is with qtagg (or likely tkagg should work too).