注册的ACTION_HEADSET_PLUG监听器仅触发几次

Question

我想要在插入耳机后显示通知，并在拔出耳机后隐藏它。因此，我在一个在BOOT_COMPLETED触发的BroadCastReceiver中注册了ACTION_HEADSET_PLUG意图侦听器。在我的例子中，我使用HTC Sense (HTC One S)，只有当我插入耳机，而Sense正在加载(WaitDialog)时，通知才会显示，之后它就不会再显示了。

如果我在运行时通过‘OnBootListener OnBootreceiver().onReceive(this，null)’触发应用程序中的新函数，它就能完美地工作。

清单：

...
<uses-permission android:name="android.permission.RECEIVE_BOOT_COMPLETED"/>

<application
    android:icon="@drawable/ic_launcher"
    android:label="@string/app_name" >
    <activity
        ...
    </activity>

    <receiver android:name=".OnBootReceiver" >
        <intent-filter>
            <action android:name="android.intent.action.BOOT_COMPLETED" />
        </intent-filter>
    </receiver>
 ...

OnBootReceiver：

public void onReceive(Context context, Intent intent) {
    IntentFilter receiverFilter = new IntentFilter(Intent.ACTION_HEADSET_PLUG);
    HeadsetStateReceiver receiver = new HeadsetStateReceiver();
    context.registerReceiver( receiver, receiverFilter );
}

HeadsetStateReceiver：

public void onReceive(Context context, Intent intent) {
    Toast.makeText(context,
            "" + (Integer) (intent.getExtras().get("state")),
            Toast.LENGTH_SHORT).show();
    mNotificationManager = (NotificationManager) context
            .getSystemService(Context.NOTIFICATION_SERVICE);

    Log.e(this.getClass().toString(), "Intent Headset_plug received "
            + intent);
    if ((Integer) (intent.getExtras().get("state")) != 0) {
        notification.flags = Notification.FLAG_ONGOING_EVENT;
        notification.contentIntent = PendingIntent.getActivity(
                context.getApplicationContext(), 0, new Intent(), 0);
        notification.setLatestEventInfo(context, title, message,
                notification.contentIntent);
        mNotificationManager.notify(0xBEA15, notification);
    } else {
        mNotificationManager.cancelAll();
    }

}

Answer 1

为什么需要BOOT_COMPLETED接收器？您是否尝试使用清单文件接收ACTION_HEADSET_PLUG？

<application 
    android:icon="@drawable/ic_launcher" 
    android:label="@string/app_name" > 
    <activity 
        ... 
    </activity> 

    <receiver android:name=".HeadsetStateReceiver" > 
        <intent-filter> 
            <action android:name="android.intent.ACTION_HEADSET_PLUG" /> 
        </intent-filter> 
    </receiver> 

你的代码也有点小气：

public void onReceive(Context context, Intent intent) {
    boolean isConnected = intent.getIntExtra("state",0)==1; // Can also be 2 if headset is attached w/o mic.

    Toast.makeText(context, 
            isConnected?"connected":"disconnected"), 
            Toast.LENGTH_SHORT).show(); 
    mNotificationManager = (NotificationManager) context 
        .getSystemService(Context.NOTIFICATION_SERVICE); 

    if (isConnected) {
        Log.e(this.getClass().toString(), "Intent Headset_plug connected");
        notification.flags = Notification.FLAG_ONGOING_EVENT; 
        notification.contentIntent = PendingIntent.getActivity( 
                context.getApplicationContext(), 0, new Intent(), 0); 
        notification.setLatestEventInfo(context, title, message, 
                notification.contentIntent); 
        mNotificationManager.notify(0xBEA15, notification); 
    } else {
        Log.e(this.getClass().toString(), "Intent Headset_plug disconnected");
        mNotificationManager.cancelAll(); 
    } 
} 

​

Ok直接接收器将不工作(here is good explanation)。

​

我想我知道为什么你的接收器在一段时间后停止工作。您的应用程序必须由系统清理。为了让它工作，你必须做一些事情来阻止你的应用程序被清理。所以你必须创建一个服务。在BOOT_COMPLETED中启动一个服务，并在该服务中为ACTION_HEADSET_PLUG注册广播接收器。这应该可以防止应用程序被清理。

Answer 2

您的代码是正确的，但据我所知，您不能将HEADSET_PLUG过滤器放在清单上。取而代之的是，从清单中删除接收器，并以编程方式从应用程序的某个部分执行此操作。主活动的onCreate()方法应该没问题，例如：

ReceiveBroadcast receiver=new ReceiveBroadcast();       
registerReceiver(receiver, new IntentFilter(Intent.ACTION_HEADSET_PLUG));