为 Android 上的媒体 Mounted/Removed 事件动态创建接收器

Dynamically created receiver for Media Mounted/Removed events on Android

虽然 activity 是可见的,但我希望在设备安装或移除媒体时通知它。不幸的是,我无法收到这些通知。我唯一能得到的是 foo!,这是我创建的一个简单测试。

public class MyActivity extends AppCompatActivity {

  private BroadcastReceiver receiver = new BroadcastReceiver() {
    @Override
    public void onReceive(Context context, Intent intent) {
        Log.e(ActivityFamily.class.getName(), intent.getAction());
    }
  };

  @Override
  protected void onResume() {
    super.onResume();
    IntentFilter filter = new IntentFilter();
    filter.addAction("foo!");
    filter.addAction(Intent.ACTION_MEDIA_EJECT);
    filter.addAction(Intent.ACTION_MEDIA_REMOVED);
    filter.addAction(Intent.ACTION_MEDIA_MOUNTED);
    filter.addAction(Intent.ACTION_MEDIA_BAD_REMOVAL);
    registerReceiver(receiver, filter);

    // just added this as a test for "foo!" action
    AlarmManager manager = (AlarmManager) getSystemService(Context.ALARM_SERVICE);
    manager.set(AlarmManager.ELAPSED_REALTIME, SystemClock.elapsedRealtime() + 2000, PendingIntent.getBroadcast(this, 0, new Intent().setAction("foo!"), 0));
  }

  @Override
  protected void onPause() {
    super.onPause();
    unregisterReceiver(receiver);
  }
}

为什么当我从设备中删除媒体时 onReceive 没有被调用?

我什至尝试创建一个全新的 MyReceiver.java 并在 AndroidManifest.xml 中定义它,但这也没有用。

<receiver android:name=".MyReceiver">
    <intent-filter>
        <action android:name="android.intent.action.MEDIA_EJECT" />
        <action android:name="android.intent.action.MEDIA_REMOVED" />
        <action android:name="android.intent.action.MEDIA_MOUNTED" />
        <action android:name="android.intent.action.MEDIA_BAD_REMOVAL" />
        <data android:scheme="file" />
    </intent-filter>
</receiver>

I found the answer here. 我需要将 file: 方案添加到 intent 过滤器中。

在使用 registerReceiver 之前添加 filter.addDataScheme("file");

对于在清单中注册的静态广播接收器,在 <intent-filter>.

中添加 <data android:scheme="file" />