Increase Value Of TextView

Developing an app for scoreboard. And I am having a hard time for I don't have much background to Java as well as the Android.

I am developing my program but it seems It really giving me hard time regarding TextView.XD .How do you increase the value of TextView where its value is e.g. is 0?Just like in Scoreboard. Increasing the value of score as you click the TextView assigned to it.

This is my code:

private OnClickListener mHscoreListener = new OnClickListener() {
public void onClick(View v) {
//DO INCREASE
};};