从具有相同未决意图的另一个活动中取消警报

Question

我有一个问题，整天搜索，但无法正确解决

如何取消另一个活动的警报（alarm_Time 活动）？我认为我的问题在于我曾经取消 设置警报的相同pendingintent

这里是alarm_Time活动中取消闹钟的代码：

    final Intent intent = getIntent();
    int alarm_No = intent.getIntExtra("alarm_No",0);
    pending_intent = PendingIntent.getBroadcast(alarm_Time.this,alarm_No, intent, PendingIntent.FLAG_UPDATE_CURRENT);


    //intialize alarm_off button
    Button alarm_off = (Button) findViewById(R.id.alarm_off);
    // create on click listner to end alarm
    //final Intent finalIntent = intent;
    alarm_off.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            //method that change update_txt txtbox
                              // set_alarm_text("Alarm off!");
            //cancel the alarm
            alarmManager.cancel(pending_intent);
            // put extra string into my_intent
            // tells the clock that you pressed the "alarm off" button
            intent.putExtra("extra", "alarm off");
            // stop the ringtone
            sendBroadcast(intent);
        }
    });

我设置警报的活动代码（MainActivity2）：

    protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main2);
    Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
    setSupportActionBar(toolbar); ///
    this.context = this ;

    update_txt = (TextView) findViewById(R.id.update_txt);
    info_txt = (TextView) findViewById(R.id.info_txt);

    final int[] h = {21, 21};
    final int[] m = {15, 16};
    final int length = h.length;

    final Intent[] intent = new Intent[length];
    final Calendar[] cal = new Calendar[length];
    final AlarmManager[] alarmManager = new AlarmManager[length];
    final PendingIntent[] pending_intent = new PendingIntent[length]; ;

    for(int i =0; i<length; i++) {
        cal[i] = Calendar.getInstance();
        cal[i].set(Calendar.HOUR_OF_DAY, h[i]);
        cal[i].set(Calendar.MINUTE, m[i]);
        if (cal[i].getTimeInMillis() < System.currentTimeMillis())
        {    cal[i].add(Calendar.DAY_OF_MONTH, 1);  }

        intent[i] = new Intent(this.context, AlarmReceiver.class);
        alarmManager[i] = (AlarmManager) getSystemService(ALARM_SERVICE);

    }



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

            String h1_string = String.valueOf(h[0]);
            String m1_string = String.valueOf(m[0]);


  for(int i =0; i<length; i++) {


      set_alarm_text("Alarm on!" + h1_string + ":" + m1_string);
      intent[i].putExtra("extra", "alarm on");
      intent[i].putExtra("Alarm_no", i);
      pending_intent[i] = PendingIntent.getBroadcast(MainActivity2.this, i, intent[i], PendingIntent.FLAG_UPDATE_CURRENT );
      alarmManager[i].set(AlarmManager.RTC_WAKEUP, cal[i].getTimeInMillis(), pending_intent[i]);

  }


        }
    });

    //intialize alarm_off button
    Button alarm_off = (Button) findViewById(R.id.alarm_off);
    // create on click listner to end alarm
    alarm_off.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            Bundle extras = getIntent().getExtras();
            int alarm_No = -1;
            if (extras != null) {
                alarm_No = extras.getInt("alarm_No2");
            }

            Log.v("help", String.valueOf(alarm_No));

            set_alarm_text("Alarm off!");
            alarmManager[0].cancel(pending_intent[0]);
            intent[0].putExtra("extra", "alarm off");
            sendBroadcast(intent[0]);
        }
    });
}

private void set_alarm_text(String output) {
    update_txt.setText(output);
}

private void set_info_text(String output) {
    info_txt.setText(output);
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
    getMenuInflater().inflate(R.menu.menu_main, menu);
    return true;
}
@Override
public boolean onOptionsItemSelected(MenuItem item) {

    int id = item.getItemId();
    if (id == R.id.action_settings) {
        return true;
    }
    return super.onOptionsItemSelected(item);
}

}

AlarmReceiver.java

public class AlarmReceiver extends BroadcastReceiver{


@Override
public void onReceive(Context context, Intent intent) {
    Log.e("We are in the receiver", "Yay");

     //fetch extra strings from the intent   >>>  get_ur_string =extra //   alarm on - alarm off
    String get_ur_string = intent.getExtras().getString("extra");
    int No = intent.getExtras().getInt("Alarm_no");


  //  Log.e("What is the key? ", get_ur_string);


    //create an intent to the ringtone service
    Intent service_intent = new Intent(context, RingtonePlayingService.class);

    // pass the extra from Main Activity to Ringtone Playing Service
    service_intent.putExtra("extra", get_ur_string);
    service_intent.putExtra("Alarm_no", No);

    //start the ringtone services
    context.startService(service_intent);



}

}

RingtonePlayingService.java

public class RingtonePlayingService extends Service {

MediaPlayer media_song;
int startId;
boolean isRunning;

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

public int onStartCommand(Intent intent, int flags, int startId)
{
    Log.i("LocalService", "Received start id " + startId +": " + intent);

    // fetch the extra string values
    String state = intent.getExtras().getString("extra");
    int alarm_No = intent.getExtras().getInt("Alarm_no");

    // Log.e("Ringtone state:extra", state);


    // notification
    // set up the notification service
    NotificationManager notify_manager = (NotificationManager)
            getSystemService(NOTIFICATION_SERVICE);
    // set up an intent that goes to the Main Activity
    Intent intent_main_activity = new Intent(this.getApplicationContext(), MainActivity2.class);
    intent.putExtra("extra", "alarm on");
    intent.putExtra("Alarm_no2", alarm_No);
    // set up a pending intent
    PendingIntent pending_intent_main_activity = PendingIntent.getActivity(this, alarm_No,
            intent_main_activity, 0);

    // make the notification parameters
    Notification notification_popup = new Notification.Builder(this)
            .setContentTitle("An alarm is going off!")
            .setContentText("Click me!")
            .setSmallIcon(R.drawable.image)

            .setContentIntent(pending_intent_main_activity)
            .setAutoCancel(true)
            .build();

    // set up notification atart command
    notify_manager.notify(0, notification_popup);




    // this converts the extra strings from the intent to start IDs, values 0 or 1
    assert state != null;
    switch (state) {
        case "alarm on":
            startId = 1;
            int alarm_num = intent.getExtras().getInt("No");
            break;
        case "alarm off":
            startId = 0;
            Log.e("Start ID is", state);
            break;
        default:
            startId = 0;
            break;
    }

    // if else statments

    // if there is no music playing, and the user pressing "alarm on"
    // music should start playing
    if( !this.isRunning && startId == 1  ){
        Log.e("there is no music","and u want start");
        // create an instant of the media player
        media_song = MediaPlayer.create(this, R.raw.tone);
        // start the ringtone
        media_song.start();

        this.isRunning = true;
        this.startId = 0;

    }
    // if there is music playing, and the user pressing "alarm off"
    // music should stop playing
    else  if( this.isRunning && startId == 0 ){
        Log.e("there is  music", "and u want stop");

        // stop the ringtone
        media_song.stop();
        media_song.reset();

        this.isRunning = false;
        this.startId = 0;

    }





    return START_NOT_STICKY;
}

@Override
public void onDestroy() {
    //tell the user we stopped
    Log.e("on Destroy called", "ta da");

    super.onDestroy();
    this.isRunning = false;

}

}

Answer 1

您正在尝试通过这种方式取消来自Activity 的警报：

final Intent intent = getIntent();
int alarm_No = intent.getIntExtra("alarm_No",0);
pending_intent = PendingIntent.getBroadcast(alarm_Time.this,alarm_No, intent, PendingIntent.FLAG_UPDATE_CURRENT);
...
//cancel the alarm
alarmManager.cancel(pending_intent);

但你是这样设置闹钟的：

intent[i] = new Intent(this.context, AlarmReceiver.class);
intent[i].putExtra("Alarm_no", i);
pending_intent[i] = PendingIntent.getBroadcast(MainActivity2.this, i, intent[i], PendingIntent.FLAG_UPDATE_CURRENT );
alarmManager[i].set(AlarmManager.RTC_WAKEUP, cal[i].getTimeInMillis(), pending_intent[i]);

您使用了错误的Intent。在您的Activity 中，当您调用getIntent() 时，它将返回用于启动Activity 的Intent。您在致电PendingIntent.getBroadcast() 时使用它。这不会返回正确的PendingIntent。您需要将设置警报时使用的Intent 传递给PendingIntent.getBroadcast() 的呼叫。这应该看起来像这样：

final Intent intent = new Intent(this, AlarmReceiver.class);
int alarm_No = intent.getIntExtra("alarm_No",0);
pending_intent = PendingIntent.getBroadcast(alarm_Time.this,alarm_No, intent, PendingIntent.FLAG_UPDATE_CURRENT);
...
//cancel the alarm
alarmManager.cancel(pending_intent);

另外，我注意到你在 extra 中传递了警报号码，如下所示：

intent[i].putExtra("Alarm_no", i);

使用密钥"Alarm_no"，但您尝试使用alarmtime_Activity获取警报号

int alarm_No = intent.getIntExtra("alarm_No",0);

使用密钥"alarm_No"。这些键只是Strings，所以它们区分大小写。您是否有可能没有使用完全相同的密钥？我不知道，因为你还没有发布你用来启动 alarmtime_Activity 的代码。