你应该实现一个广播接收器并监听android.intent.action.PROVIDER_CHANGED"意图

you should implement a broadcast receiver and listen to "android.intent.action.PROVIDER_CHANGED" intent

<receiver android:name="GmailReceiver">
        <intent-filter>
            <action android:name="android.intent.action.PROVIDER_CHANGED"
                android:priority="-10">
            </action>
            <action android:name="android.intent.action.VIEW" />
            <data android:scheme="content" android:host="gmail-ls"
                android:pathPattern="/unread/.*">
            </data>
        </intent-filter>
    </receiver>