Merge pull request matplotlib#19611 from anntzer/2pick

Fix double picks.

Author: QuLogic

lib/matplotlib/backend_bases.py

@@ -1726,15 +1726,13 @@ def __init__(self, figure=None):
         self._button = None  # the button pressed
         self._key = None  # the key pressed
         self._lastx, self._lasty = None, None
-        self.button_pick_id = self.mpl_connect('button_press_event', self.pick)
-        self.scroll_pick_id = self.mpl_connect('scroll_event', self.pick)
         self.mouse_grabber = None  # the axes currently grabbing mouse
         self.toolbar = None  # NavigationToolbar2 will set me
         self._is_idle_drawing = False
 
-    @property
-    def callbacks(self):
-        return self.figure._canvas_callbacks
+    callbacks = property(lambda self: self.figure._canvas_callbacks)
+    button_pick_id = property(lambda self: self.figure._button_pick_id)
+    scroll_pick_id = property(lambda self: self.figure._scroll_pick_id)
 
     @classmethod
     @functools.lru_cache()

lib/matplotlib/figure.py

@@ -2106,6 +2106,10 @@ def __init__(self,
         # a proxy property), but that actually need to be on the figure for
         # pickling.
         self._canvas_callbacks = cbook.CallbackRegistry()
+        self._button_pick_id = self._canvas_callbacks.connect(
+            'button_press_event', lambda event: self.canvas.pick(event))
+        self._scroll_pick_id = self._canvas_callbacks.connect(
+            'scroll_event', lambda event: self.canvas.pick(event))
 
         if figsize is None:
             figsize = mpl.rcParams['figure.figsize']

lib/matplotlib/tests/test_backend_bases.py

@@ -120,6 +120,19 @@ def test_location_event_position(x, y):
         assert re.match("x=foo +y=foo", ax.format_coord(x, y))
 
 
+def test_pick():
+    fig = plt.figure()
+    fig.text(.5, .5, "hello", ha="center", va="center", picker=True)
+    fig.canvas.draw()
+    picks = []
+    fig.canvas.mpl_connect("pick_event", lambda event: picks.append(event))
+    start_event = MouseEvent(
+        "button_press_event", fig.canvas, *fig.transFigure.transform((.5, .5)),
+        MouseButton.LEFT)
+    fig.canvas.callbacks.process(start_event.name, start_event)
+    assert len(picks) == 1
+
+
 def test_interactive_zoom():
     fig, ax = plt.subplots()
     ax.set(xscale="logit")