android - 警报没有停止

Question

我正在使用 android 和广播接收器处理警报。可以设置和播放闹钟，但我无法关闭闹钟。我有两个用于设置闹钟和停止闹钟的按钮。我的代码在这里；

public class MainActivity extends AppCompatActivity {
Button btn;

private Button startAlarmBtn;
private TimePickerDialog timePickerDialog;
final static int REQUEST_CODE = 1;

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);
     Button cancel;



            startAlarmBtn = (Button) findViewById(R.id.startAlarmBtn);
            startAlarmBtn.setOnClickListener(new View.OnClickListener() {
                @Override
                public void onClick(View v) {
                    openPickerDialog(false);
                }
            });


    cancel=(Button)findViewById(R.id.cancel);
    cancel.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            stopAlarm();
        }
    });
}
private void openPickerDialog(boolean is24hour) {

    Calendar calendar = Calendar.getInstance();

    timePickerDialog = new TimePickerDialog(
            MainActivity.this,
            onTimeSetListener,
            calendar.get(Calendar.HOUR_OF_DAY),
            calendar.get(Calendar.MINUTE),
            is24hour);
    timePickerDialog.setTitle("Alarm Ayarla");

    timePickerDialog.show();
}

TimePickerDialog.OnTimeSetListener onTimeSetListener
        = new TimePickerDialog.OnTimeSetListener(){

    @Override
    public void onTimeSet(TimePicker view, int hourOfDay, int minute) {

        Calendar calNow = Calendar.getInstance();
        Calendar calSet = (Calendar) calNow.clone();

        calSet.set(Calendar.HOUR_OF_DAY, hourOfDay);
        calSet.set(Calendar.MINUTE, minute);
        calSet.set(Calendar.SECOND, 0);
        calSet.set(Calendar.MILLISECOND, 0);

        if(calSet.compareTo(calNow) <= 0){

            calSet.add(Calendar.DATE, 1);
        }

        setAlarm(calSet);
    }};

private void setAlarm(Calendar alarmCalender){

    Toast.makeText(getApplicationContext(),"Alarm OK!",Toast.LENGTH_SHORT).show();
    Intent intent = new Intent(getBaseContext(), AlarmReceiver.class);
    PendingIntent pendingIntent = PendingIntent.getBroadcast(getBaseContext(), REQUEST_CODE, intent, 0);
    AlarmManager alarmManager = (AlarmManager)getSystemService(Context.ALARM_SERVICE);
    alarmManager.set(AlarmManager.RTC_WAKEUP, alarmCalender.getTimeInMillis(), pendingIntent);

}
private void stopAlarm(){

    PendingIntent pendingIntent = PendingIntent.getBroadcast(getApplicationContext(), REQUEST_CODE,
            new Intent(getApplicationContext(), AlarmReceiver.class), PendingIntent.FLAG_UPDATE_CURRENT);

    AlarmManager manager = (AlarmManager) getSystemService(Context.ALARM_SERVICE);
    pendingIntent.cancel();


}
}


public class AlarmReceiver extends BroadcastReceiver {
@Override
public void onReceive(Context context, Intent intent) {

    Uri alarmUri = RingtoneManager.getDefaultUri(RingtoneManager.TYPE_ALARM);
    if (alarmUri == null)
    {
        alarmUri = RingtoneManager.getDefaultUri(RingtoneManager.TYPE_NOTIFICATION);
    }
    Ringtone ringtone = RingtoneManager.getRingtone(context, alarmUri);
    ringtone.play();
}


}

如何关闭闹钟？
我的另一个问题是，将它们放在主线程中是否合适？
我应该使用 AsyncTask 还是多线程？

谢谢。

Answer 1

闹钟没有停止，因为您没有正在播放的铃声实例的句柄。我建议你添加一个计时器来自动停止铃声，或者你创建一个铃声的全局实例，再想想这可能是个坏主意，因为如果你忘记清理，它可能会泄漏并导致其他问题。

一个简单的计时方法如下所示:

public class AlarmReceiver extends BroadcastReceiver {
@Override
public void onReceive(Context context, Intent intent) {

    Uri alarmUri = RingtoneManager.getDefaultUri(RingtoneManager.TYPE_ALARM);
    if (alarmUri == null)
    {
        alarmUri = RingtoneManager.getDefaultUri(RingtoneManager.TYPE_NOTIFICATION);
    }
    Ringtone ringtone = RingtoneManager.getRingtone(context, alarmUri);
    ringtone.play();

new CountDownTimer(30000, 1000) { // a timer for 30 seconds, that updates approximately every second
 public void onTick(long millisUntilFinished) {
  }
  public void onFinish() {
// stop your ringtone here, or do other necessary stuff here
// you might want to check if the ringtone was not stopped before this method
 }
}.start();
}
}

在回答您的第二个问题时，您也可以使用带有处理程序的线程或可运行的线程来相应地管理铃声。对于相对简单的事情，AsyncTask 可能工作量太大。