Question

我正在尝试使用以下代码为“推送通知”找到前台或后台，但是它同时执行后台和前台。有什么解决办法吗？

public static boolean isAppIsInBackground(Context context) {
    boolean isInBackground = true;
    ActivityManager am = (ActivityManager) context.getSystemService(Context.ACTIVITY_SERVICE);
    if (Build.VERSION.SDK_INT > Build.VERSION_CODES.KITKAT_WATCH) {
        List<ActivityManager.RunningAppProcessInfo> runningProcesses = am.getRunningAppProcesses();
        for (ActivityManager.RunningAppProcessInfo processInfo : runningProcesses) {
            if (processInfo.importance == ActivityManager.RunningAppProcessInfo.IMPORTANCE_FOREGROUND) {
                for (String activeProcess : processInfo.pkgList) {
                    if (activeProcess.equals(context.getPackageName())) {
                        isInBackground = false;
                    }
                }
            }
        }
    } else {
        List<ActivityManager.RunningTaskInfo> taskInfo = am.getRunningTasks(1);
        ComponentName componentInfo = taskInfo.get(0).topActivity;
        if (componentInfo.getPackageName().equals(context.getPackageName())) {
            isInBackground = false;
        }
    }
    return isInBackground;
}

Answer 1

因此，如果我理解您的问题，您想检查当前线程是否为主线程/某些后台线程，您可以像这样检查它：

if(Looper.myLooper() == Looper.getMainLooper()){
  //you are on your main Thread (also called UI Thread)
}

Answer 2

让您的Application类实现LifecycleObserver接口，您可以定义如下所示的方法来获取应用前景和应用背景事件的回调

class MyApplication implements LifecycleObsercer {

    @OnLifecycleEvent(Lifecycle.Event.ON_STOP)
    public void onAppBackgrounded() {
        Timber.d("App in background");
    }

    @OnLifecycleEvent(Lifecycle.Event.ON_START)
    public void onAppForegrounded() {
        Timber.d("App is in foreground");
    }
}

如何检查应用程序是在后台还是前台android。使用以下代码但无法检查

2 个答案: