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android - Why the onPause method is called immediately after onCreate

I'm writing an application that show an activity at fixed time.

I start the activity from service with such code:

intent.setClass(context, FakeAction.class);
intent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
context.startActivity(intent);

in the onCreate method of FakeAction I require wake up of device and start sound message:

getWindow().addFlags(WindowManager.LayoutParams.FLAG_SHOW_WHEN_LOCKED);
getWindow().addFlags(WindowManager.LayoutParams.FLAG_DISMISS_KEYGUARD);
getWindow().addFlags(WindowManager.LayoutParams.FLAG_KEEP_SCREEN_ON);
getWindow().addFlags(WindowManager.LayoutParams.FLAG_TURN_SCREEN_ON);

There is a lot of code in onCreate to show information on screen and start the sound message.

Here is an onPause method:

@Override
protected void onPause()
{
    Log.i(TAG, "onPause");

    //Stop mediaPlayer
    if(mp != null)
    {
        if(mp.isPlaying())mp.stop();
        mp.release();
        mp = null;
    }

    //Restore volume
    if(audioManager != null)
    {
        audioManager.setStreamVolume(AudioManager.STREAM_ALARM, savedVolume, 0);
    }

    //Stop minute timer
    handler.removeCallbacks(minuteReceiver);

    super.onPause();
}

Unfortunately the onPause() method is called immediately after onCreate. So my sound message is immediately stopped.

But if the activity is started when the screen is not locked then the onPasue() is not called immediately after onCreate();

Even though I comment all of "getWindow().addFlags()" strings the onPause() is called after onCreate() when the screen if locked.

The question is why onPause is called immediately after onCreate? How can I distinguish immediate call of onPause() method and call of onPause() when user press the back button?

Below is the code of the activity. I use the MVP pattern, so, the main code is in presenter. But even if I comment all presenter's calls (like I done in this example) the onPause() is called immediately after onCreate()

Can it have a sence that I start activity in AsyncTask? The AsyncTask is started form service. The service is stopped after the AsyncTask if finished.

public class FakeAction extends RoboActivity
                            implements 
                            View.OnClickListener
                            ,AlarmAction
{
    private static final String TAG = "TA FakeAction";

    @InjectView(R.id.aa_btn_Stop)       Button btnStop;
    @InjectView(R.id.aa_btn_Snooze)     Button btnSnooze;
    @InjectView(R.id.aa_tv_CurTime)     TextView tvCurTime;
    @InjectView(R.id.aa_tv_CurDate)     TextView tvCurDate;
    @InjectView(R.id.aa_tv_AlarmName)   TextView tvAlarmName;

    @Inject public AlarmActionPresenter presenter;

    private Exception   ex;

    @Override
    public void onCreate(Bundle savedInstanceState)
    {
        Log.i(TAG, "onCreate");

        super.onCreate(savedInstanceState);

        getWindow().addFlags(WindowManager.LayoutParams.FLAG_SHOW_WHEN_LOCKED);
        getWindow().addFlags(WindowManager.LayoutParams.FLAG_DISMISS_KEYGUARD);
        getWindow().addFlags(WindowManager.LayoutParams.FLAG_KEEP_SCREEN_ON);
        getWindow().addFlags(WindowManager.LayoutParams.FLAG_TURN_SCREEN_ON);

        setContentView(R.layout.alarm_action);

        try
        {
            //presenter.onCreate(this);
        }
        catch(Exception ex)
        {
            this.ex = ex;
            Log.e(TAG, "onCreate",  ex);
        }

        btnStop.setOnClickListener(this);
        btnSnooze.setOnClickListener(this);


    }

    @Override
    protected void onPause()
    {
        Log.i(TAG, "onPause");

        //presenter.onPause();

        super.onPause();
    }

    @Override
    public void onClick(View v)
    {
        Log.i(TAG, "onClick");

        //presenter.onClick(v.getId());

    }

    @Override
    public Bundle getIntentBundle()
    {
        return getIntent().getExtras();
    }

    @Override
    public void setAlarmName(String alarmName)
    {
        tvAlarmName.setText(alarmName);
    }

    @Override
    public String getAlarmName()
    {
        return tvAlarmName.getText().toString();
    }

    @Override
    public void setCurTime(String curTime)
    {
        tvCurTime.setText(curTime);
    }

    @Override
    public String getCurTime()
    {
        return tvCurTime.getText().toString();
    }

    @Override
    public void setCurDate(String curDate)
    {
        tvCurDate.setText(curDate);
    }

    @Override
    public String getCurDate()
    {
        return tvCurDate.getText().toString();
    }



    @Override
    public IAssetFileDescriptorMockable openFd(String assetName) throws IOException
    {
        Log.i(TAG, "openFd");
        return new AssetFileDescriptorMockable(getAssets().openFd(assetName));
    }

}
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1 Answer

0 votes
by (71.8m points)

I found out the solution of my problem.

The reason why the onPause called after onCreate is the ActivityManager. In the log I've found the line immediately after onCreate: "Activity pause timeout for HistoryRecord" So, next events happened in my Activity:

  1. onCreate()
  2. onStart()
  3. onResume()
  4. Activity pause timeout for HistoryRecord
  5. onPause()
  6. onResume()

I don't know how to prevent the "Activity pause timeout for HistoryRecord" but I changed my application so it starts the sound message in onResume(). Even though it is stopped in onPause() it is started again in next onResume().


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