android - 工作重复 alarmmanager 不起作用，接收器不启动

Question

public void schedule()
{
    Long time = new GregorianCalendar().getTimeInMillis()+10*1000;
    Intent intent = new Intent(getActivity(), AlarmReceiver.class);
    AlarmManager alarmManager = (AlarmManager) getActivity().getSystemService(Context.ALARM_SERVICE);
    alarmManager.setInexactRepeating(AlarmManager.RTC_WAKEUP, time, 10*1000, PendingIntent.getBroadcast(getActivity(), 1,  intent, PendingIntent.FLAG_UPDATE_CURRENT));
}

上面这是我在 fragment 中的方法。也在 Activity 中尝试过。奇怪的是，这段代码适用于一个空的测试项目。我在这里看到的问题是最后一部分 alarmManager.setInexactRepeating() 根本没有启动 AlarmReceiver.class。

我在这里做错了什么？

我的 list 文件:

    <receiver android:name=".AlarmReceiver"/> 
    <uses-permission android:name="com.android.alarm.permission.SET_ALARM"/>

也是我的接收器:

public class AlarmReceiver extends BroadcastReceiver {
    @Override
    public void onReceive(Context context, Intent intent){
        Toast.makeText(context, "Alarm Triggered and SMS Sent", Toast.LENGTH_LONG).show();
    }
}

Answer 1

因为 setInexactRepeating。使用 setRepeating，它会在正确的时间被处理。

代替:

setInexactRepeating 

使用

setRepeating

setInexactRepeating，对操作系统和电池友好，它将所有要在 Alarm receive 上完成的工作分批处理并一个接一个地工作，而 setRepeating 会立即触发警报

另请注意:一旦手机重新启动，警报就会消失，您可能必须实现启动广播接收器以使其持久存在。确保你不执行该运行时，你需要在 list 中实现它，否则当你的应用程序不在后台时你将不会收到任何广播。

一个小例子:

这是工作代码。它每 10 分钟唤醒一次 CPU，直到手机关机。

添加到 Manifest.xml:

...
<uses-permission android:name="android.permission.WAKE_LOCK"></uses-permission>
...
<receiver  android:process=":remote" android:name="Alarm"></receiver>
...

代码:

    package YourPackage;
    import android.app.AlarmManager;
    import android.app.PendingIntent;
    import android.content.BroadcastReceiver;
    import android.content.Context;
    import android.content.Intent;
    import android.os.PowerManager;
    import android.widget.Toast;

    public class Alarm extends BroadcastReceiver 
    {    
         @Override
         public void onReceive(Context context, Intent intent) 
         {   
             PowerManager pm = (PowerManager) context.getSystemService(Context.POWER_SERVICE);
             PowerManager.WakeLock wl = pm.newWakeLock(PowerManager.PARTIAL_WAKE_LOCK, "");
             wl.acquire();

             // Put here YOUR code.
             Toast.makeText(context, "Alarm !!!!!!!!!!", Toast.LENGTH_LONG).show(); // For example

             wl.release();
         }

     public void SetAlarm(Context context)
     {
         AlarmManager am=(AlarmManager)context.getSystemService(Context.ALARM_SERVICE);
         Intent i = new Intent(context, Alarm.class);
         PendingIntent pi = PendingIntent.getBroadcast(context, 0, i, 0);
         am.setRepeating(AlarmManager.RTC_WAKEUP, System.currentTimeMillis(), 1000 * 60 * 10, pi); // Millisec * Second * Minute
     }

     public void CancelAlarm(Context context)
     {
         Intent intent = new Intent(context, Alarm.class);
         PendingIntent sender = PendingIntent.getBroadcast(context, 0, intent, 0);
         AlarmManager alarmManager = (AlarmManager) context.getSystemService(Context.ALARM_SERVICE);
         alarmManager.cancel(sender);
     }
 }

从服务设置警报:

package YourPackage;
import android.app.Service;
import android.content.Context;
import android.content.Intent;
import android.os.IBinder;

public class YourService extends Service
{
    Alarm alarm = new Alarm();
    public void onCreate()
    {
        super.onCreate();       
    }

    public void onStart(Context context,Intent intent, int startId)
    {
        alarm.SetAlarm(context);
    }

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

如果你想在手机开机时设置闹钟重复:

向 Manifest.xml 添加权限:

<uses-permission android:name="android.permission.RECEIVE_BOOT_COMPLETED"></uses-permission>
...
<receiver android:name=".AutoStart">
    <intent-filter>
        <action android:name="android.intent.action.BOOT_COMPLETED"></action>
    </intent-filter>
</receiver>
...

并创建新类:

package YourPackage;
import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.Intent;

public class AutoStart extends BroadcastReceiver
{   
    Alarm alarm = new Alarm();
    @Override
    public void onReceive(Context context, Intent intent)
    {   
        if (intent.getAction().equals("android.intent.action.BOOT_COMPLETED"))
        {
            alarm.SetAlarm(context);
        }
    }
}