JSplitPane hide and show the right section

Question

I have a JSplitPane with two sections. I want to hide the right section when I click a button, and bring it back when I click on that same button again.

Here is what I have so far:

private void jButton1ActionPerformed(java.awt.event.ActionEvent evt) {                                         
    if (PrincipalSplitPane.getDividerSize() == 1.0)
        PrincipalSplitPane.setDividerLocation(0.0);
    else
        PrincipalSplitPane.setDividerLocation(1.0);
    }

Answer 1

You can use the getRightComponent() method of the JSplitPane and then call the setVisible(false) to hide it.

To show it again, call the setVisible(true) and set the divider location using the setDividerLocation(...) method.

An Example

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

import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.JSplitPane;
import javax.swing.SwingUtilities;

@SuppressWarnings("serial")
public class ResizingSplitPane extends JFrame implements ActionListener
{

    private JButton clickMe;
    private JPanel leftPanel;
    private JPanel rightPanel;
    private JSplitPane split;

    // private int dividerLocation;

    public ResizingSplitPane()
    {
        setSize(300, 300);
        setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        setLocationRelativeTo(null);
        setLayout(new BorderLayout());

        // Center Panel
        clickMe = new JButton("Click Me!!");
        clickMe.addActionListener(this);

        JPanel panel = new JPanel(new BorderLayout());

        panel.add(clickMe);

        // Bottom Panel
        leftPanel = new JPanel(new BorderLayout());
        rightPanel = new JPanel(new BorderLayout());

        leftPanel.add(new JLabel("Left"), BorderLayout.CENTER);
        rightPanel.add(new JLabel("Right"), BorderLayout.CENTER);

        split = new JSplitPane(JSplitPane.HORIZONTAL_SPLIT, leftPanel, rightPanel);
        split.setResizeWeight(.5d);

        add(panel, BorderLayout.PAGE_START);
        add(split, BorderLayout.CENTER);

        setVisible(true);
    }

    public static void main(String[] args)
    {
        SwingUtilities.invokeLater(new Runnable()
        {
            @Override
            public void run()
            {
                new ResizingSplitPane();
            }
        });
    }

    @Override
    public void actionPerformed(ActionEvent e)
    {

        if (e.getSource() == clickMe)
        {
            if (split.getRightComponent().isVisible())
            {
                // dividerLocation = split.getDividerLocation();
                split.getRightComponent().setVisible(false);
            }
            else
            {
                split.getRightComponent().setVisible(true);
                split.setDividerLocation(0.5);
            }
        }
    }

}

If you need to save the previous divider location, you can store the current location into a variable (like the dividerLocation variable in the code) and then when calling the setDividerLocation pass in that variable.