屏幕关闭时启动应用程序答案

【问题标题】：Start app when screen off屏幕关闭时启动应用程序
【发布时间】：2013-01-21 09:18:26
【问题描述】：

我想在屏幕关闭时打开我的 MainActivity 类。为了做到这一点，我做了两堂课 ScreenReceiver.java 处理屏幕关闭和屏幕开启意图：

public class ScreenReceiver extends BroadcastReceiver {

 private boolean screenOff;

    @Override
    public void onReceive(Context context, Intent intent) {
        if (intent.getAction().equals(Intent.ACTION_SCREEN_OFF)) {
            screenOff = true;
        } else if (intent.getAction().equals(Intent.ACTION_SCREEN_ON)) {
            screenOff = false;
        }
        Intent i = new Intent(context, UpdateService.class);
        i.putExtra("screen_state", screenOff);
        context.startService(i);
    }

}

以及用于实现 ScreenReceiver 的 UpdateService：

public  class UpdateService extends Service {

@Override
public void onCreate() {
    super.onCreate();
    // register receiver that handles screen on and screen off logic
    IntentFilter filter = new IntentFilter(Intent.ACTION_SCREEN_ON);
    filter.addAction(Intent.ACTION_SCREEN_OFF);
    BroadcastReceiver mReceiver = new ScreenReceiver();
    registerReceiver(mReceiver, filter);
}

public void onStart(Context context, Intent intent, int startId) {
    boolean screenOn = intent.getBooleanExtra("screen_state", false);
    if (!screenOn) {
        // your code
         Intent intent11 = new Intent(context,MainActivity.class);
         intent11.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
         context.startActivity(intent11);
    } else {
        // your code
        Intent intent11 = new Intent(context,MainActivity.class);
        intent11.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
    }
}

@Override
public IBinder onBind(Intent intent) {
    // TODO Auto-generated method stub
    return null;
}

}

所以，当我安装我的应用程序时，屏幕关闭时没有任何事件。请告诉我问题。

【问题讨论】：

标签： android screen

【解决方案1】：

您是否在应用程序的某处前台启动了 UpdateService？？

【讨论】：

【解决方案2】：

首先，意图ACTION_SCREEN_OFF 和ACTION_SCREEN_ON 只能由通过函数registerReceiver() 注册的接收者处理。在 manifest.xml 中定义 IntentFilter 不适用于这些意图。

然后，您需要确保在您的应用程序中调用UpdateService:onCreate()，否则永远不会调用ScreenReceiver:onReceiver()。你可能想在获取意图时这样做BOOT_COMPLETED。

你可以把代码改成这样，别忘了在 manifest 中定义服务：

public class UpdateService extends Service {

    BroadcastReceiver mReceiver = new BroadcastReceiver {
    private boolean screenOff;

    @Override
    public void onReceive(Context context, Intent intent) {
        if (intent.getAction().equals(Intent.ACTION_SCREEN_OFF)) {
            screenOff = true;
        } else if (intent.getAction().equals(Intent.ACTION_SCREEN_ON)) {
            screenOff = false;
        }
        handleScreenAction(screenOff);
    }

    private void handleScreenAction(boolean screenOff) {
        if (screenOff) {
            // your code
            Intent intent11 = new Intent(context,MainActivity.class);
            intent11.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
            context.startActivity(intent11);
        } else {
            // your code
            Intent intent11 = new Intent(context,MainActivity.class);
            intent11.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
        }
    }

    @Override
    public void onCreate() {
        super.onCreate();
        // register receiver that handles screen on and screen off logic
        IntentFilter filter = new IntentFilter(Intent.ACTION_SCREEN_ON);
        filter.addAction(Intent.ACTION_SCREEN_OFF);
        registerReceiver(mReceiver, filter);
    }

    @Override
    public void onDestory() {
        super.onDestory();
        unRegisterReceiver(mReceiver);
    }

    public void onStart(Context context, Intent intent, int startId) {
    }

    @Override
    public IBinder onBind(Intent intent) {
    // TODO Auto-generated method stub
        return null;
    }
}

【讨论】：