How to reset class variable to default value 0?

Question

If anybody can tell me different way to do this, I would appreciate. How to reset class variable to 0, or default value? I use class variable cause I don't know another way to do this. After my game ends I place result in class variable, cause I have two rounds of my game, and after first round ends I add the result, and class variable is good for this cause even after I restart my game method it still holds my previous result. After second round is over I add that result to previous result and then close the activity and set text result as text to a button. But when I click New game, that button still holds that text, cause class variable still holds it. How to reset that class variable when I go on New game?

Here's my game code, some of it (100 points are start amount, and it gets lower in game progress):

public class Asocijacije extends Activity implements OnClickListener{

int brojPoenaAsocijacije = 100;
    public static int brojPoenaUkupno;

Then I skip here a lot of code and here's where I add points. brojPoenaAsocijacije are points earned in that round:

brojPoenaUkupno = brojPoenaUkupno + brojPoenaAsocijacije;

Here's my main activity where I set points from my class variable to a button (where I added comment):

public class Izbor extends Activity implements OnClickListener{

    Asocijacije poeni = new Asocijacije();

    Button toploHladno, asocijacije, cigle, spojnice, nazad, poeniTH, poeniAso, poeniCigle, poeniSpojnice;
    TextView naslov;
    public boolean music;
    MediaPlayer buttonClicks, buttonBack;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);

        requestWindowFeature(Window.FEATURE_NO_TITLE);   //full screen
        getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN, WindowManager.LayoutParams.FLAG_FULLSCREEN);

        setContentView(R.layout.izbor);

        SharedPreferences getPrefs = PreferenceManager.getDefaultSharedPreferences(getBaseContext());
        music = getPrefs.getBoolean("checkbox", true);

        addListenerOnButton();

    }



    private void addListenerOnButton() {
        buttonClicks = MediaPlayer.create(this, R.raw.click);
        buttonBack = MediaPlayer.create(this, R.raw.button31);

        Typeface naslovType = Typeface.createFromAsset(getAssets(), "Lobster.ttf");
        Typeface dugmad = Typeface.createFromAsset(getAssets(), "Bebas.ttf");
        naslov = (TextView) findViewById(R.id.tvIzborNaslov);
        toploHladno = (Button) findViewById(R.id.bIzbor1);
        asocijacije = (Button) findViewById(R.id.bIzbor2);
        cigle = (Button) findViewById(R.id.bIzbor3);
        spojnice = (Button) findViewById(R.id.bIzbor4);
        nazad = (Button) findViewById(R.id.bIzborNazad);
        poeniTH = (Button) findViewById(R.id.bPoeniTH);
        poeniAso = (Button) findViewById(R.id.bPoeniAso);
        poeniCigle = (Button) findViewById(R.id.bPoeniCigle);
        poeniSpojnice = (Button) findViewById(R.id.bPoeniSpojnice);
        naslov.setTypeface(naslovType);
        toploHladno.setTypeface(dugmad);
        asocijacije.setTypeface(dugmad);
        cigle.setTypeface(dugmad);
        spojnice.setTypeface(dugmad);
        nazad.setTypeface(dugmad);
        poeniAso.setTypeface(dugmad);

        toploHladno.setOnClickListener(this);
        asocijacije.setOnClickListener(this);
        cigle.setOnClickListener(this);
        spojnice.setOnClickListener(this);
        nazad.setOnClickListener(this);

    }


    @Override
    protected void onStart() {
        super.onStart(); 
        poeniAso.setText("" + poeni.brojPoenaUkupno); //I do it here
    }

    public void onClick(View v) {
        switch(v.getId()){
        case R.id.bIzbor1:
            if(music == true){
                buttonClicks.start();
                    }
            startActivity(new Intent("rs.androidaplikacije.toplo_hladno.GAME"));
            break;
        case R.id.bIzbor2:
            if(music == true){
                buttonClicks.start();
                    }
            startActivity(new Intent("rs.androidaplikacije.toplo_hladno.ASOCIJACIJE"));
            break;
        case R.id.bIzbor3:
            if(music == true){
                buttonClicks.start();
                    }

            break;
        case R.id.bIzbor4:
            if(music == true){
                buttonClicks.start();
                    }

            break;
        case R.id.bIzborNazad:
            if(music == true){
                buttonBack.start();
                    }
            poeniAso.setText("");
            finish();
            break;
        }

    }

}

Answer 1

Probably want to reset your state when you close the in-game activity.

@Override
protected void onDestroy() {
    super.onDestroy();
    Asocijacije.brojPoenaUkupno = 0;
    //whatever other things need to be reset.
}

Answer 2

Because I don't find the piece of code where you start the new game, I can only say:

Asocijacije.brojPoenaUkupno = 0;