Merge pull request matplotlib#22711 from andrew-fennell/RangeSlider-bugfix

RangeSlider handle set_val bugfix

Author: QuLogic

lib/matplotlib/tests/test_widgets.py

@@ -1105,19 +1105,30 @@ def test_range_slider(orientation):
     # Check initial value is set correctly
     assert_allclose(slider.val, (0.1, 0.34))
 
+    def handle_positions(slider):
+        if orientation == "vertical":
+            return [h.get_ydata()[0] for h in slider._handles]
+        else:
+            return [h.get_xdata()[0] for h in slider._handles]
+
     slider.set_val((0.2, 0.6))
     assert_allclose(slider.val, (0.2, 0.6))
+    assert_allclose(handle_positions(slider), (0.2, 0.6))
+
     box = slider.poly.get_extents().transformed(ax.transAxes.inverted())
     assert_allclose(box.get_points().flatten()[idx], [0.2, .25, 0.6, .75])
 
     slider.set_val((0.2, 0.1))
     assert_allclose(slider.val, (0.1, 0.2))
+    assert_allclose(handle_positions(slider), (0.1, 0.2))
 
     slider.set_val((-1, 10))
     assert_allclose(slider.val, (0, 1))
+    assert_allclose(handle_positions(slider), (0, 1))
 
     slider.reset()
-    assert_allclose(slider.val, [0.1, 0.34])
+    assert_allclose(slider.val, (0.1, 0.34))
+    assert_allclose(handle_positions(slider), (0.1, 0.34))
 
 
 def check_polygon_selector(event_sequence, expected_result, selections_count,

lib/matplotlib/widgets.py

@@ -813,7 +813,10 @@ def _update_val_from_pos(self, pos):
             val = self._max_in_bounds(pos)
             self.set_max(val)
         if self._active_handle:
-            self._active_handle.set_xdata([val])
+            if self.orientation == "vertical":
+                self._active_handle.set_ydata([val])
+            else:
+                self._active_handle.set_xdata([val])
 
     def _update(self, event):
         """Update the slider position."""
@@ -836,11 +839,16 @@ def _update(self, event):
             return
 
         # determine which handle was grabbed
-        handle = self._handles[
-            np.argmin(
+        if self.orientation == "vertical":
+            handle_index = np.argmin(
+                np.abs([h.get_ydata()[0] - event.ydata for h in self._handles])
+            )
+        else:
+            handle_index = np.argmin(
                 np.abs([h.get_xdata()[0] - event.xdata for h in self._handles])
             )
-        ]
+        handle = self._handles[handle_index]
+
         # these checks ensure smooth behavior if the handles swap which one
         # has a higher value. i.e. if one is dragged over and past the other.
         if handle is not self._active_handle:
@@ -904,14 +912,22 @@ def set_val(self, val):
             xy[2] = .75, val[1]
             xy[3] = .75, val[0]
             xy[4] = .25, val[0]
+
+            self._handles[0].set_ydata([val[0]])
+            self._handles[1].set_ydata([val[1]])
         else:
             xy[0] = val[0], .25
             xy[1] = val[0], .75
             xy[2] = val[1], .75
             xy[3] = val[1], .25
             xy[4] = val[0], .25
+
+            self._handles[0].set_xdata([val[0]])
+            self._handles[1].set_xdata([val[1]])
+
         self.poly.xy = xy
         self.valtext.set_text(self._format(val))
+
         if self.drawon:
             self.ax.figure.canvas.draw_idle()
         self.val = val