How to implement onPause() and onResume?

Question

When I'm leaving my app, my counter gets reset.

I know that I need to use the onPause and onResume functions. However, I don't know how to write it in the code.

 @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        final Button b1 = findViewById(R.id.b1);

        eggcounter = 100;
        final ImageButton ImgButton = findViewById(R.id.eggBtn);

        ImgButton.setOnClickListener(
                new View.OnClickListener() {

                    public void onClick(View view) {
                        eggcounter = eggcounter - 1;
                        updateEgg();

                        if (eggcounter < 80) {

                            ImgButton.setImageResource(R.drawable.egg_2);

                            if (eggcounter <60){
                                ImgButton.setImageResource(R.drawable.egg_3);

                                if (eggcounter <40) {
                                    ImgButton.setImageResource(R.drawable.egg_4);

[Read the docs](https://developer.android.com/guide/components/activities/activity-lifecycle). — Matt Clark, May 04 '19 at 21:55
Possible duplicate of [onPause() and onStop() in Activity](https://stackoverflow.com/questions/11387258/onpause-and-onstop-in-activity) — Matt Clark, May 04 '19 at 21:56

score 1 · Accepted Answer · answered May 05 '19 at 01:02

If you want to save your application state, you can use Shared Preferences. Example :

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        // You can call to onResume() or on Pause() in onCreate();
        onResume();
        onPause();
    }

    @Override
    public void onResume() {
        super.onResume();
        // After receiving this call you will usually receive a following call 
        // to onStop() and return to your activity 's onResume()
    }

    @Override
    public void onPause() {
        super.onPause();
        // When you receive a call, your activity is going into the background 
        // (to onPause) but your activity can be killed to reclaim resources 
        // (if there are not enough resources to start the new activity)
    }

so if you want to save your instance application state, you can save to Shared Preferences, SQLite and so on. Call it in onPause() or onStop() and reclaim this data in onResume()

How to implement onPause() and onResume?

1 Answers1