优化代码，优化demo

app/src/main/res/menu/menu_single_task_activity.xml

@@ -0,0 +1,12 @@
+<?xml version="1.0" encoding="utf-8"?>
+<menu xmlns:android="http://schemas.android.com/apk/res/android"
+    xmlns:app="http://schemas.android.com/apk/res-auto">
+
+  <item
+      android:id="@+id/help"
+      android:icon="@mipmap/ic_help_black_48dp"
+      android:orderInCategory="90"
+      android:title="tip"
+      app:showAsAction="ifRoom"
+      />
+</menu>