Question

我是Android新手。我正在尝试创建一个使用BroadcastReceiver来执行由重复警报触发的主要活动的函数的应用程序。我读到我必须动态注册我所做的broadcastReceiver - 这是为了能够在主要活动上执行该功能。我面临的问题是，一旦退出应用程序，alarm就会停止工作。我读到这是设计 - 有没有办法克服这个问题，还是我必须使用service？提前谢谢。

示例代码：

public class AlarmReceiver extends BroadcastReceiver {  
    @Override  
    public void onReceive(Context context, Intent intent) {  
        Toast.makeText(context, "from AlarmReceiver", Toast.LENGTH_SHORT).show();  
    }
}

public class MainActivity extends AppCompatActivity {  
    private PendingIntent pendingIntent;  
    private AlarmManager manager;  
    private AlarmReceiver myReceiver = null;  
    @Override  
    protected void onCreate(Bundle savedInstanceState) {  
        super.onCreate(savedInstanceState);  
        setContentView(R.layout.activity_main);  
        myReceiver = new AlarmReceiver();  
        IntentFilter myIntentFilter = new IntentFilter("ANY_ACTION");  
        registerReceiver(myReceiver,  myIntentFilter);  
        Intent myIntent = new Intent();  
        myIntent.setAction("ANY_ACTION");  
        pendingIntent = PendingIntent.getBroadcast(this, 0,myIntent,0);  
    }  
      public void startAlarm(View view) {  
        manager = (AlarmManager)getSystemService(Context.ALARM_SERVICE);  
        int interval = 1500;  
        manager.setRepeating(AlarmManager.RTC_WAKEUP, System.currentTimeMillis(),   interval, pendingIntent);  
        Toast.makeText(this, "Alarm Set", Toast.LENGTH_LONG).show();  
    }     
}

Answer 1

我认为，当您的应用未运行时，闹钟停止工作的原因是您在registerReceiver本地注册 AlarmReceiver 。如果您想注册AlarmReceiver以便即使您的应用程序未运行也能继续工作，您需要在AndroidManifest.xml内注册它。

首先，将您的收件人添加到AndroidManifest.xml，如下所示：

  <application>    
       //...
       <receiver android:name=".AlarmReceiver">
        </receiver>
       //...
  </application>

并设置你的闹钟（记住：不要设置闹钟间隔太短，设置至少1分钟;你在你的代码中设置你的间隔1.5秒 - 它可能不起作用）：

    int interval = 60 * 1000;
    Intent intent=new Intent(this, AlarmReceiver.class);
    PendingIntent pendingIntent = PendingIntent.getBroadcast(this, 1, intent, 0);
    AlarmManager alarmManager = (AlarmManager) getSystemService(Context.ALARM_SERVICE);
    alarmManager.setRepeating(AlarmManager.RTC_WAKEUP, System.currentTimeMillis(), interval, pendingIntent);

在onRecieve中触发警报时，只需执行您想要执行的操作：

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

    AudioManager audioManager = (AudioManager)context.getSystemService(Context.AUDIO_SERVICE);
    SharedPreferences sharedPreferences = context.getSharedPreferences("Settings", 0);
    int iDefValue=0; 
    int iDayAlarmVal= sharedPreferences.getInt("something", iDefValue); 
    // and so on...
                 }
         }

在现有使用广播接收器的应用程序之后，有没有办法让重复警报工作？

1 个答案: