whenever i run my app, and press the button; it displays the fact in the did you know section

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

    //declare our view variables and then assign view from the layout file..
    final TextView factTextView = (TextView) findViewById(R.id.factTextView);
    final Button showFactButton = (Button) findViewById(R.id.showFactButton);
    View.OnClickListener listener = new View.OnClickListener(){
        @Override
        public void onClick(View view)
        {
            //the button was clicked update the fact label with a new fact
            String fact = "ostriches can run faster than a house.";
            factTextView.setText(fact);

         }

    };
    showFactButton.setOnClickListener(listener);
}


@Override
public boolean onCreateOptionsMenu(Menu menu) {
    // Inflate the menu; this adds items to the action bar if it is present.
    getMenuInflater().inflate(R.menu.funfacts, 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();
    if (id == R.id.action_settings) {
        return true;
    }
    return super.onOptionsItemSelected(item);
}