access class members from main

Question

i'm working with swing builder in java, the form: but I can't access the components from main: how can I get access to the form components?

Answer 1

The issue is that your private JButton startBtn needs to be declared static in order to be accessed within the main method: private static JButton startBtn;

You should also instantiate it as a new object within the main before calling anything on it: startBtn = new JButton(...);

It's also worth noting, by convention, your class name should be FirstSwingForm, and think through whether or not those instance variables will be used elsewhere or if they can be defined within main.

Answer 2

This is how I solved it

public class firstSwingForm {
private JPanel config;
private JTextField startTxt;
private JTextField dogTextField;
private JPanel mainPanel;
private JTextField a5TextField;
private JButton startBtn;
private static firstSwingForm instance;

public static void main(String args[]) {
    JFrame frame = new JFrame("App");
    instance = new firstSwingForm();
    frame.setContentPane(instance.mainPanel);
    frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    frame.pack();
    frame.setVisible(true);
    instance.startBtn.setText("text can be set");