为什么不在操作栏中显示菜单项？

Question

I try to show once menu item in action bar .Now all items showing into the menu.But I want once items showing out of menu in action bar .

<menu xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    tools:context="com.example.nabege.Show_subject_Activity" >

    <item
        android:id="@+id/about_us"
        android:title="@string/about_us"/>
    <item
        android:id="@+id/help"
        android:title="@string/help"/>
    <item
        android:id="@+id/setting"
        android:title="@string/setting"/>
    <item
        android:id="@+id/collectionName"
        android:title=""
        app:showAsAction="always"/>

</menu>

In this case I set the title of item via programing. I want my menu like this image:

Answer 1

I change this line and solved :

 <item
        android:id="@+id/collectionName"
        android:title=""
        showAsAction="always"/>