How to make a counter

MainActivity.java

package com.example.mjdicken.helloworld;

import android.app.Activity;
import android.os.Bundle;
import android.view.View;
import android.view.Menu;
import android.view.MenuItem;
import android.widget.Button;
import android.widget.TextView;

import java.lang.String;
public class MainActivity extends Activity implements View.OnClickListener {
    private TextView theCount;
    private Button theButton;
    private int number = 0;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        theButton = (Button) findViewById(R.id.theButton);
        theCount = (TextView) findViewById(R.id.count);
        theButton.setOnClickListener(this);

    }

    @Override
    public void onClick(View v){
        number++;
        System.out.println(number);
        theCount.setText(""+number);
    }
    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        // Inflate the menu; this adds items to the action bar if it is present.
        getMenuInflater().inflate(R.menu.menu_main, menu);
        return true;
    }


    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
        // Handle action bar item clicks here. The action bar will
        // automatically handle clicks on the Home/Up button, so long
        // as you specify a parent activity in AndroidManifest.xml.
        int id = item.getItemId();

        //noinspection SimplifiableIfStatement
        if (id == R.id.action_settings) {
            return true;
        }

        return super.onOptionsItemSelected(item);
    }
}