Save Countdowntimer on activity destroy and resume it in onResume()

Question

I want to start a counter for 2 minute and when activity destroy then i want to save that and on activity resume i want to start the counter where i left

counter = new CountDownTimer(120000, 1000) { // adjust the milli seconds here

        public void onTick(long millisUntilFinished)
        {
            textview.setText("" + String.format("%d min, %d sec",
                    TimeUnit.MILLISECONDS.toMinutes(millisUntilFinished),
                    TimeUnit.MILLISECONDS.toSeconds(millisUntilFinished) -
                            TimeUnit.MINUTES.toSeconds(TimeUnit.MILLISECONDS.toMinutes(millisUntilFinished))));

            Log.i(TAG, "onTick: "+millisUntilFinished);
        }

        public void onFinish()
        {
            textview.setText("done!");
        }
    }.start();

Answer 1

We just save a value of millisUntilFinished when activity is destroy and create new CountDownTimer with that value when activity start again.

long millisUntilFinished;

in onDestroy() (or onStop())

@Override
    public void onDestroy() {
        SharedPreferences.Editor editor = getSharedPreferences(MY_PREFS_NAME, MODE_PRIVATE).edit();
        editor.putLong("millisUntilFinished", millisUntilFinished);
        editor.apply();
        super.onDestroy();
    }

and get value of millisUntilFinished when you want to start the CountDownTimer

        SharedPreferences prefs = getSharedPreferences(MY_PREFS_NAME, MODE_PRIVATE);
        millisUntilFinished = prefs.getLong("millisUntilFinished", 120000);

        counter = new CountDownTimer(millisUntilFinished, 1000) { // adjust the milli seconds here

            public void onTick(long millisUntilFinished) {
                this.millisUntilFinished = millisUntilFinished;
                textview.setText("" + String.format("%d min, %d sec",
                        TimeUnit.MILLISECONDS.toMinutes(millisUntilFinished),
                        TimeUnit.MILLISECONDS.toSeconds(millisUntilFinished)
                                - TimeUnit.MINUTES.toSeconds(
                                TimeUnit.MILLISECONDS.toMinutes(millisUntilFinished))));

                Log.i(TAG, "onTick: " + millisUntilFinished);
            }

            public void onFinish() {
                textview.setText("done!");
            }
        }.start();