How to flush print statement to Button in Android Studio?

Question

I am making a simple tic tac toe game and I want to immediately print the X's and O's when a player presses a button. Just like how you could flush a print statement and immediately have the buffer empty itself without having to go through the whole program.

    // method to print X's and O's on buttons
    private void setText(Button btn) {

        if (btn.getText().toString().equals("")) { // if button NOT toggled yet
            if (state == 0) { // print 0 on button
                btn.setText("0");
                moves++;
                state = 1;
            } else { // print X on button
                btn.setText("X");
                moves++;
                state = 0;
            }
        }
    }