<?xml version="1.0" encoding="utf-8"?>
<menu xmlns:android="http://schemas.android.com/apk/res/android">

    <item
        android:id="@+id/item1"
        android:showAsAction="ifRoom"
        android:title="Open activities"
        android:checkable="true" />
</menu>
<?xml version="1.0" encoding="utf-8"?>
<menu xmlns:android="http://schemas.android.com/apk/res/android">

    <item
        android:id="@+id/action_customize"
        android:showAsAction="ifRoom"
        android:title="@string/customize"
        android:icon="@drawable/ic_action_customize"
        android:checkable="true" />
</menu>
Move string form menu to resources and change id menu item
Move string form menu to resources and change id menu item
