diff --git a/src/com/android/calculator2/ColorButton.java b/src/com/android/calculator2/ColorButton.java
index de330e2..c9bab40 100644
--- a/src/com/android/calculator2/ColorButton.java
+++ b/src/com/android/calculator2/ColorButton.java
@@ -128,6 +128,7 @@
                 break;
             case MotionEvent.ACTION_DOWN:
             case MotionEvent.ACTION_CANCEL:
+                mAnimStart = -1;
                 invalidate();
                 break;
         }