广播没有开始

Question

这是我第一次尝试创建 android 应用程序。我正在尝试创建一个可以在后台计数的服务，我希望该服务将时间广播给接收者。不过，接收者似乎没有收到任何东西，所以我不确定我的服务是否开始了。

这是我尝试启动服务并创建接收器的代码：

  @Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);
    IntentFilter filter = new IntentFilter();
    filter.addAction("EXAMPLE_BROADCAST");

    clock = (TextView) findViewById(R.id.textClock);

    timeReceiver = new BroadcastReceiver() {
        @Override
        public void onReceive(Context context, Intent intent) {
            setClock(intent.getLongExtra("counter", 0));
        }
    };

    registerReceiver(timeReceiver,filter);

    startService(new Intent(this, CounterService.class));
}

public void setClock(long time){
    clock.setText(String.valueOf(time));
}

这是我的服务 class:

public class CounterService extends Service {
private Handler handler;
private long initialTime;
private long timeInMilliseconds = 0L;
private boolean isActive;
Intent timeBroadcaster = new Intent("EXAMPLE_BROADCAST");

@Override
public void onCreate(){
    super.onCreate();

    Runnable counter = new Runnable() {
        @Override
        public void run() {
            isActive = ((PowerManager) getSystemService(Context.POWER_SERVICE)).isInteractive();
            if(isActive) {
                timeInMilliseconds += 1000;
                handler.postDelayed(this, 1000);
            }
            else {
                if(timeInMilliseconds > 5000) {
                    timeInMilliseconds = 0;
                }
                handler.postDelayed(this, 1000);
            }
            timeBroadcaster.putExtra("counter", timeInMilliseconds);
            sendBroadcast(timeBroadcaster);
        }
    };
}


@Override
public IBinder onBind(Intent intent) {
    return null;
}

}

感谢任何帮助，谢谢。

Answer 1

您需要注册您的接收器。

在你的activity的onStart方法中

IntentFilter filter = new IntentFilter();
filter.addAction("YOUR_ACTION");
registerReceiver(timeReceiver, filter)

在你的activity的onStop方法中

unregisterReceiver(timeReceiver)

在发送广播之前将您的操作添加到 Intent

timeBroadcaster.setAction("YOUR_ACTION");

Answer 2

Runnable本身不会执行，需要交给线程。

Runnable counter = new Runnable() {
        @Override
        public void run() {
            isActive = ((PowerManager) getSystemService(Context.POWER_SERVICE)).isInteractive();
            if(isActive) {
                timeInMilliseconds += 1000;
                handler.postDelayed(this, 1000);
            }
            else {
                if(timeInMilliseconds > 5000) {
                    timeInMilliseconds = 0;
                }
                handler.postDelayed(this, 1000);
            }
            timeBroadcaster.putExtra("counter", timeInMilliseconds);
            sendBroadcast(timeBroadcaster);
        }
    };

Thread thread = new Thread(counter);
thread.start();

同时在清单中注册您的服务：

<!--Register service-->
  <service android:name="yourpackage.CounterService" />

广播没有开始

Broadcast doesn't get started

android

broadcast