android - 使用 cancel 取消 AlarmManager 事件

Question

PendingIntent cancel() API 文档说:

Cancel a currently active PendingIntent. Only the original application owning a PendingIntent can cancel it.

我不太清楚这句话的意思。如果我像这样从 Activity x 设置 AlarmManager 事件:

PendingIntent pendingIntent;
Intent myIntent = new Intent(x.this, AlarmReciever.class);

myIntent.putExtra("task_uuid", task_uuid);
pendingIntent = PendingIntent.getBroadcast(x.this, 0, myIntent,0);
AlarmManager alarmManager = (AlarmManager)getSystemService(ALARM_SERVICE);
alarmManager.set(AlarmManager.RTC, dateTime.getTimeInMillis(), pendingIntent);

我的问题是:我可以使用以下方法取消 y Activity 中的未决 Intent 吗:

PendingIntent pendingIntent;
Intent myIntent = new Intent(y.this, AlarmReciever.class);

myIntent.putExtra("task_uuid", task_uuid);
pendingIntent = PendingIntent.getBroadcast(y.this, 0, myIntent,0);
AlarmManager alarmManager = (AlarmManager)getSystemService(ALARM_SERVICE);
alarmManager.cancel(pendingIntent);

Answer 1

当你设置闹钟时需要在PendingIntent中传递一个键值，它会区分是否有闹钟，应该是这样的

pendingIntent = PendingIntent.getBroadcast(x.this, key_value, myIntent,0);
SharedPreferences settings = context.getSharedPreferences("alarm", 0);
SharedPreferences.Editor editor = settings.edit();       
editor.putBoolean(key, false);  
editor.commit(); 

要取消相同的警报，您需要将 key_values 保存在某个位置，您可以使用共享首选项。得到相同的 key 然后像这样取消警报

SharedPreferences settings = context.getSharedPreferences("alarm", 0);             
Map<String,?> allNotifyIdsMap = settings.getAll();      
if(allNotifyIdsMap!=null&&allNotifyIdsMap.isEmpty()==false)
{       
   for(String notifyId: allNotifyIdsMap.keySet())
   {
      boolean isCleared = settings.getBoolean(notifyId, false);
      if(isCleared==false)
      {
          pendingIntent = PendingIntent.getBroadcast(y.this, key_value, myIntent,0);
          AlarmManager alarmManager = (AlarmManager)getSystemService(ALARM_SERVICE);
          alarmManager.cancel(pendingIntent);  
      }
   }
}