android:parentActivityName

在manifest.xml文件中指定Activity的父Activity

<application ... >

	<activity
        	android:name=" com.example.myfirstapp.MainActivity "
        	android:label="@string/title_activity_main_message"
		<intent-filter>
           		<action android:name="android.intent.action.MAIN" />
           		<category android:name="android.intent.category.LAUNCHER" />
    		</intent-filter>
    	</activity>

     	<activity
        	android:name="com.example.myfirstapp.DisplayMessageActivity"
        	android:label="@string/title_activity_display_message"
        	android:parentActivityName="com.example.myfirstapp.MainActivity" >
        	<meta-data
            		android:name="android.support.PARENT_ACTIVITY"
            		android:value="com.example.myfirstapp.MainActivity" />
    	</activity>
</application>

The android:parentActivityName attribute declares the name of this activity's parent activity within the app's logicalhierarchy. The system uses this value to implement default navigationbehaviors, such asUp navigationon Android 4.1 (API level 16) and higher.

 You can provide the same navigation behaviors for older versions of Android by using the SupportLibrary and adding the<meta-data> element as shown here.