ScrollBar is not working when Layout is null

Question

Scroolbar doesnt appear when the layout set to null. How to get the scrollbar inside the panel? Is there any other way to achieve it. I want to get the scroll bar in the scrollPane

import java.awt.Dimension;

import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.JScrollPane;

public class ScrollBarExample {

    public static void main(String... args) {
        JFrame frame = new JFrame();
        JPanel panel = new JPanel();
        panel.setLayout(null);
        for (int i = 0; i < 10; i++) {
            JButton jbutton = new JButton("Hello-" + i);
            jbutton.setBounds(i * 100, i*30, 100, 40);
            panel.add(jbutton);
        }
        JScrollPane scrollPane = new JScrollPane(panel);
        scrollPane.setHorizontalScrollBarPolicy(JScrollPane.HORIZONTAL_SCROLLBAR_AS_NEEDED);
        scrollPane.setVerticalScrollBarPolicy(JScrollPane.VERTICAL_SCROLLBAR_AS_NEEDED);
        scrollPane.setBounds(50, 10, 320, 100);
        JPanel contentPane = new JPanel(null);
        contentPane.setPreferredSize(new Dimension(500, 400));
        contentPane.add(scrollPane);
        frame.setContentPane(contentPane);
        frame.pack();
        frame.setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);
        frame.setVisible(true);
    }
}

I hate to sound like a jerk, but isn't the obvious solution then to either remove 'panel.setLayout(null);' or to not put a null value as the LayoutManager? — mbw, Aug 13 '14 at 15:49

score 3 · Accepted Answer · answered Aug 13 '14 at 16:00

3

Without Layout-Manager you need to set the Preferred-Size of the Panel by hand

panel.setPreferredSize(new Dimension(500, 500));

for example

answered Aug 13 '14 at 16:00

Angelus

46
2

1

[Don't use `setPreferredSize()` when you really mean to override `getPreferredSize()`](http://stackoverflow.com/q/7229226/230513). – trashgod Aug 13 '14 at 16:10

ScrollBar is not working when Layout is null

1 Answers1