Adding JPanel to JScrollPane

Question

I have a gui which has a Panel that contains a sequence of labels and TextFields and uses a spring layout(this is the mainPanel) and another Panel that just contains a button(bu

Answer 1

• I can't comment something, to try and compare

• notice in this moment I don't understand why SpringLayout and JFrame#pack() doesn't build proper GUI based on PreferredSize, bump in this looks like as (in this moment) my issue too

code with hardcoded JFrame.setSize() instead of proper JFrame#pack()

import java.awt.BorderLayout;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.JTextField;
import javax.swing.SpringLayout;
import javax.swing.SwingUtilities;

public class Main {

    public Main() {
        JFrame frame = new JFrame("SpringLayout");
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        JButton next = new JButton("Next");
        JPanel buttonPanel = new JPanel();
        buttonPanel.add(next);
        SpringLayout layout = new SpringLayout();
        JPanel mainPanel = new JPanel();
        mainPanel.setLayout(layout);
        int j = 25;
        for (int i = 0; i < 5; i++) {
            JLabel label = new JLabel("Enter Name");
            JTextField text = new JTextField(15);
            layout.putConstraint(SpringLayout.WEST, label, 10, SpringLayout.WEST,
                    mainPanel);
            layout.putConstraint(SpringLayout.NORTH, label, j, SpringLayout.NORTH,
                    mainPanel);
            layout.putConstraint(SpringLayout.NORTH, text, j, SpringLayout.NORTH,
                    mainPanel);
            layout.putConstraint(SpringLayout.WEST, text, 20, SpringLayout.EAST,
                    label);
            j += 30;
            mainPanel.add(label);
            mainPanel.add(text);
        }
        frame.add(mainPanel, BorderLayout.CENTER);
        frame.add(buttonPanel, BorderLayout.SOUTH);
        frame.setSize(300, 300);
        frame.setVisible(true);
    }

    public static void main(String args[]) {
        SwingUtilities.invokeLater(new Runnable() {

            @Override
            public void run() {
                 Main mn = new Main();
            }
        });
    }
}