AlarmManager和服务不能在我的应用程序工作

Question

我想要一个简单的计时器执行一组命令，它需要是准确的。如果应用程序被最小化（隐藏）或手机处于睡眠状态（CPU睡眠），它也必须继续。我已经看过帖子在这些网站上：

Site 1

Site 2

我试图理解代码，并将其添加到我自己的新项目，但应用程序关闭的开始。这是我的。

MainActivity的onCreate（）

 Intent myAlarm = new Intent(getApplicationContext(), AlarmReceiver.class); 
     PendingIntent recurringAlarm = PendingIntent.getBroadcast(getApplicationContext(), 0, myAlarm, PendingIntent.FLAG_CANCEL_CURRENT); 
     AlarmManager alarms = (AlarmManager) this.getSystemService(Context.ALARM_SERVICE); 
     Calendar updateTime = Calendar.getInstance(); 
     updateTime.setTimeInMillis(5000); // first reoccurance 
     int customInterval = 5000; // 5 seconds intervals 
     alarms.setInexactRepeating(AlarmManager.RTC_WAKEUP, updateTime.getTimeInMillis(), customInterval, recurringAlarm); 

AlarmReceiver.class/AlarmReceiver.java

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

public class AlarmReceiver extends BroadcastReceiver { 
    @Override 
    public void onReceive(Context context, Intent intent) 
    { 
     Intent myService = new Intent(context, YourService.class); 
     context.startService(myService); 
    } 
} 

YourService.class/YourService.java

import android.app.Service; 
import android.content.Intent; 
import android.os.IBinder; 

public class YourService extends Service { 
    @Override 
    public IBinder onBind(Intent intent) { // Automatically added by adding Service extension 
     // TODO Auto-generated method stub 
     return null; 
    } 
} 

清单

<manifest 
    ... > 

    <uses-sdk 
     android:minSdkVersion="8" 
     android:targetSdkVersion="17" /> 

    <application 
     ... > 

     <service android:name=".YourService"></service> 
     <receiver android:name=".AlarmReceiver"></receiver> 

     <activity 
      ... > 
      ... 
     </activity> 
    </application> 
</manifest> 

应用程序崩溃的开始。代码有什么问题？

我想要的只是应用程序通过MainActivity启动一个闹钟，它每隔一定的时间间隔执行一组命令（即使手机处于睡眠状态）。我听说要做到这一点的方法是创建一个Alarm并创建一个Service，并将命令放入服务中。

我在做什么错？

logcat的

04-25 15:49:45.799: E/AndroidRuntime(32359): FATAL EXCEPTION: main 
04-25 15:49:45.799: E/AndroidRuntime(32359): java.lang.RuntimeException: Unable to instantiate service com.example.wifischedule.YourService: java.lang.ClassCastException: com.example.wifischedule.YourService cannot be cast to android.app.Service 
04-25 15:49:45.799: E/AndroidRuntime(32359): at android.app.ActivityThread.handleCreateService(ActivityThread.java:2388) 
04-25 15:49:45.799: E/AndroidRuntime(32359): at android.app.ActivityThread.access$1600(ActivityThread.java:140) 
04-25 15:49:45.799: E/AndroidRuntime(32359): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1309) 
04-25 15:49:45.799: E/AndroidRuntime(32359): at android.os.Handler.dispatchMessage(Handler.java:99) 
04-25 15:49:45.799: E/AndroidRuntime(32359): at android.os.Looper.loop(Looper.java:137) 
04-25 15:49:45.799: E/AndroidRuntime(32359): at android.app.ActivityThread.main(ActivityThread.java:4898) 
04-25 15:49:45.799: E/AndroidRuntime(32359): at java.lang.reflect.Method.invokeNative(Native Method) 
04-25 15:49:45.799: E/AndroidRuntime(32359): at java.lang.reflect.Method.invoke(Method.java:511) 
04-25 15:49:45.799: E/AndroidRuntime(32359): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1006) 
04-25 15:49:45.799: E/AndroidRuntime(32359): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:773) 
04-25 15:49:45.799: E/AndroidRuntime(32359): at dalvik.system.NativeStart.main(Native Method) 
04-25 15:49:45.799: E/AndroidRuntime(32359): Caused by: java.lang.ClassCastException: com.example.wifischedule.YourService cannot be cast to android.app.Service 
04-25 15:49:45.799: E/AndroidRuntime(32359): at android.app.ActivityThread.handleCreateService(ActivityThread.java:2385) 
04-25 15:49:45.799: E/AndroidRuntime(32359): ... 10 more 
04-25 15:49:45.854: E/android.os.Debug(2268): !@Dumpstate > dumpstate -k -t -z -d -o /data/log/dumpstate_app_error 
04-25 15:49:52.724: E/FaceDetectionService(2268): enabled 

谢谢！

Answer 1

假设MainActivity实际上是Activity,从来没有自己实例化Android组件。

请使用Log.d()或同等方法记录Service的信息以供开发使用。

除此之外，正如Class Stacker所示，没有堆栈跟踪，很难为您提供帮助。

作为堆栈跟踪指示，YourService需要从android.app.Service继承。