View.OnClickListener

protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    // Set the content of the activity to use the activity_main.xml layout file    setContentView(R.layout.activity_main);
    TextView numbers = (TextView) findViewById(R.id.numbers);    TextView family = (TextView) findViewById(R.id.family);    TextView colours = (TextView) findViewById(R.id.colors);    TextView phrases = (TextView) findViewById(R.id.phrases);
    numbers.setOnClickListener(new View.OnClickListener() {
        @Override        public void onClick(View view) {
            Intent numbersIntent = new Intent(MainActivity.this, NumbersActivity.class);            startActivity (numbersIntent);        }
    });

}