Fix loading user-defined icons for Qt plot window

timhoffm · timhoffm · commit dab05a610d10 · 2022-01-06T23:32:24.000+01:00
diff --git a/lib/matplotlib/backends/backend_qt.py b/lib/matplotlib/backends/backend_qt.py
@@ -682,8 +682,15 @@ def _icon(self, name):
         Construct a `.QIcon` from an image file *name*, including the extension
         and relative to Matplotlib's "images" data directory.
         """
-        name = name.replace('.png', '_large.png')
-        pm = QtGui.QPixmap(str(cbook._get_data_path('images', name)))
+        # try to find a high-resolution (48x48 px) icon, which we internally
+        # store with the suffix _large
+        filepath = cbook._get_data_path('images',
+                                        name.replace('.png', '_large.png'))
+        if not filepath.exists():
+            # fallback to the given name (in particular also for user icons)
+            filepath = cbook._get_data_path('images', name)
+
+        pm = QtGui.QPixmap(str(filepath))
         _setDevicePixelRatio(pm, _devicePixelRatioF(self))
         if self.palette().color(self.backgroundRole()).value() < 128:
             icon_color = self.palette().color(self.foregroundRole())
