【轉載】http://www.crazyjiang.cn/2017/09/08/android-meta-data/

在AndroidManifest.xml中，<meta-data>元素可以作為子元素，被包含在<activity>、<application> 、<service>和<receiver>元素中，不同的父元素，在應用時讀取的方法也不同。

在Activity應用<meta-data>元素

xml:

<activity...>
    <meta-data android:name="data_Name" android:value="hello my activity"></meta-data>
</activity>

java:

ActivityInfo info = this.getPackageManager().getActivityInfo(getComponentName(), PackageManager.GET_META_DATA);
String msg = info.metaData.getString("data_Name");

在application應用<meta-data>元素

xml:

<application...>
    <meta-data android:name="data_Name" android:value="hello my application"></meta-data>
</application>

java:

ApplicationInfo info = this.getPackageManager().getApplicationInfo(getPackageName(), PackageManager.GET_META_DATA);
String msg = info.metaData.getString("data_Name");

在service應用<meta-data>元素

xml:

<service android:name="MetaDataService">
    <meta-data android:value="hello my service" android:name="data_Name"></meta-data>
</service>

java:

ComponentName cn = new ComponentName(this, MetaDataService.class);
ServiceInfo info = this.getPackageManager().getServiceInfo(cn, PackageManager.GET_META_DATA);
String msg = info.metaData.getString("data_Name");

在receiver應用<meta-data>元素

xml:

<receiver android:name="MetaDataReceiver">
    <meta-data android:value="hello my receiver" android:name="data_Name"></meta-data>
    <intent-filter>
        <action android:name="android.intent.action.PHONE_STATE"></action>
    </intent-filter>
</receiver>

java:

ComponentName cn = new ComponentName(context, MetaDataReceiver.class);
ActivityInfo info = context.getPackageManager().getReceiverInfo(cn, PackageManager.GET_META_DATA);
String msg = info.metaData.getString("data_Name");