Merge pull request #4943 from jrevans/issue15

tacaswell · tacaswell · commit c8c6fbd0221e · 2015-08-20T10:26:31.000-04:00
FIX: qt backend has more draws than necessary
diff --git a/lib/matplotlib/backends/backend_qt5agg.py b/lib/matplotlib/backends/backend_qt5agg.py
@@ -71,7 +71,9 @@ def paintEvent(self, e):
         In Qt, all drawing should be done inside of here when a widget is
         shown onscreen.
         """
-        FigureCanvasAgg.draw(self)
+        # If we have not rendered the Agg backend yet, do so now.
+        if not hasattr(self, 'renderer'):
+            FigureCanvasAgg.draw(self)
 
         # FigureCanvasQT.paintEvent(self, e)
         if DEBUG:
