Create a new random number each time an activity is opened

I'm doing a simple addition game on android studio. Every time the "addition" activity is opened I was hoping to generate two random numbers in two text boxes. However I can't get it to work and the text box appears blank every time I run the app and open the activity. Here's my code for one of the text boxes.

public void textview2(View View) {
    Random addition1 = new Random();
    int additionint1 = addition1.nextInt(100)+1;
    TextView additionText1 = (TextView) findViewById(R.id.textView2);
    String additionString1 = String.valueOf(addition1);
    additionText1.setText(additionString1);
}