diff --git a/Library/src/main/java/com/example/zhouwei/library/CustomPopWindow.java b/Library/src/main/java/com/example/zhouwei/library/CustomPopWindow.java
index eed4158..f86c621 100644
--- a/Library/src/main/java/com/example/zhouwei/library/CustomPopWindow.java
+++ b/Library/src/main/java/com/example/zhouwei/library/CustomPopWindow.java
@@ -154,6 +154,7 @@ private PopupWindow build(){
             mWindow = activity.getWindow();
             WindowManager.LayoutParams params = mWindow.getAttributes();
             params.alpha = alpha;
+            mWindow.addFlags(WindowManager.LayoutParams.FLAG_DIM_BEHIND);
             mWindow.setAttributes(params);
         }