如何查看App是否关闭或者Activity是否关闭？

Question

我有一个 android 应用程序，我需要一个功能或任何可以检查应用程序是否关闭而不是 activity 关闭的东西。我有一个这样的应用程序，如果你使用应用程序 10 秒，无论你在任何 activity，你都会收到通知“超时”。我使用计时器来做到这一点，一开始一切都很好。但是，当我关闭应用程序时，应用程序必须为下次启动保存 timeLeft。例如：如果我只剩下 5 秒，那么我关闭 App。下次我打开应用程序时，计时器将从 5 秒开始，而不是 10 秒。如果我留在 WelcomeFirst（Activity 初始化定时器）没有问题，但如果我去下一个 activity，定时器将被取消。我不想那样，只有在应用程序关闭时才会取消计时器。

有没有办法检查App是否关闭或Activity关闭？我使用 ActivityLifecycleCallbacks 和应用程序 class。我也试试这个功能

private boolean isAppRunning() {
    ActivityManager m = (ActivityManager) this.getSystemService( ACTIVITY_SERVICE );
    List<ActivityManager.RunningTaskInfo> runningTaskInfoList =  m.getRunningTasks(10);
    Iterator<ActivityManager.RunningTaskInfo> itr = runningTaskInfoList.iterator();
    int n=0;
    while(itr.hasNext()){
        n++;
        itr.next();
    }
    if(n==1){ // App is killed
        return false;
    }

    return true; // App is in background or foreground
}

没用。

我的代码

public class App extends Application implements Application.ActivityLifecycleCallbacks {

private Long START_TIME_IN_MILLIS  = 6000;
private  Boolean  mTimerRunning = false;
private Long mTimeLeftInMillis  = START_TIME_IN_MILLIS;
private  CountDownTimer mCountDownTimer;

@Override

public void onCreate() {
        super.onCreate();
       registerActivityLifecycleCallbacks(this);
    }
 @Override
    public void onActivityStarted(Activity activity) {

     //if the activity is WelcomeFirst then init the timer
      if (activity.localClassName == "WelcomeFirst") {
            SharedPreferences prefs = getSharedPreferences("prefsDay", Context.MODE_PRIVATE);
            mTimeLeftInMillis = prefs.getLong("millisLeft", 10000);
            mTimerRunning = prefs.getBoolean("timerRunning", false);
            startTimer();
        }
   
}

@Override
public void onActivityStopped(Activity activity) {

    //The code below mean if the Activity WelcomeFirst is closed then save the millisLeft for the next start.

if (activity.localClassName == "WelcomeFirst")  {
             mCountDownTimer.cancel();
              mTimerRunning = false;
            SharedPreferences prefs = getSharedPreferences("prefsDay", Context.MODE_PRIVATE);
            Editor editor = prefs.edit();
            editor.putLong("millisLeft", mTimeLeftInMillis);
            editor.putBoolean("timerRunning", mTimerRunning);
            editor.apply();
        }
       
     //I want to make the change. If The App is closed, then save the millisLeft for the next start.

     //Not the Activity is closed, then save the millisLeft for the next start
}

  private void startTimer() {
        mCountDownTimer = new CountDownTimer(mTimeLeftInMillis, 1000) {
            @Override
            public void onTick(long millisUntilFinished) {
                mTimeLeftInMillis = millisUntilFinished;
         
            }
        @Override
        public void onFinish() {
            mTimerRunning = false;
            Toast.makeText(this, "Time Out",Toast.LENGTH_SHORT).show()
        }

    }.start();
    mTimerRunning = true;
}

Answer 1

使用 processLifeCyclerManager 将解决您的问题。 https://medium.com/trendyol-tech/android-architecture-components-processlifecycleowner-26aa905d4bc5

如何查看App是否关闭或者Activity是否关闭？

How to check the App is closed or the Activity is closed?

java

android

android-lifecycle

android-activity