diff --git a/core/src/main/java/edu/umd/cs/piccolo/PCanvas.java b/core/src/main/java/edu/umd/cs/piccolo/PCanvas.java
index 673bf85..692b1b6 100644
--- a/core/src/main/java/edu/umd/cs/piccolo/PCanvas.java
+++ b/core/src/main/java/edu/umd/cs/piccolo/PCanvas.java
@@ -104,6 +104,7 @@
         setPanEventHandler(new PPanEventHandler());
         setZoomEventHandler(new PZoomEventHandler());
         setBackground(Color.WHITE);
+        setOpaque( true );
     }
 
     protected PCamera createDefaultCamera() {