import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;

import javax.swing.*;

public class RobotGui implements ActionListener {

    private JFrame frame = new JFrame();
    private JPanel panel = new JPanel();
    private JTextField textField = new JTextField(20);
    private JLabel label = new JLabel();
    private JButton button = new JButton("Start");
    private String myUserInput;

    public RobotGui(String userInput){

        myUserInput = userInput;

        frame.setTitle("Frame");
        frame.setVisible(true);
        frame.setSize(250,150);
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        frame.add(panel);
        frame.setLocationRelativeTo(null);

        label.setText("Input: ");
        panel.add(label);
        panel.add(textField);
        panel.add(button);

        frame.getContentPane().add(panel);
        button.addActionListener(this);

        //Throws pointer exception if null
        while(myUserInput == null){

            try {
                Thread.sleep(500);
            } catch (InterruptedException e) {
                JOptionPane.showMessageDialog(null, "UserInput == null error.");
            }
        }

    }

    public String getUserInput(){
        return myUserInput;
    }

    public void actionPerformed(ActionEvent e) {
        if (e.getSource() == button){
            myUserInput = textField.getText();
            frame.setVisible(false);

        }

    }

}