diff --git a/src/api-impl/android/view/WindowManager.java b/src/api-impl/android/view/WindowManager.java
index 63187156..e431f0d4 100644
--- a/src/api-impl/android/view/WindowManager.java
+++ b/src/api-impl/android/view/WindowManager.java
@@ -12,6 +12,7 @@ public interface WindowManager {
 		public int y;
 		public int windowAnimations;
 		public int flags;
+		public float alpha;
 
 		public LayoutParams(int w, int h, int type, int flags, int format) {
 			super(w, h);