How to Fix Resizing Issues with a Canvas in a JScrollPane within a JSplitPane?

Resolving Resizing Issues with Canvas within JScrollPane and JSplitPane

In the creation of a graphical user interface using NetBeans, it is common to encounter layout challenges involving resizable components within panes. This question highlights a specific issue with resizing a Canvas within a JScrollPane, which is contained within a JSplitPane.

Problem:

When reducing the size of the top component (containing the Canvas) within the JSplitPane, the divider appears to disappear beneath the Canvas and possibly the JScrollPane, causing an inconsistent layout.

Solution:

Instead of manually setting the preferred size of the components, it is recommended to allow them to calculate their preferred sizes dynamically. This can be achieved by using the pack() method on the enclosing window.

Code Example:

The provided code incorporates this approach by using the GridLayout and GraphPanel from the draw library.

import draw.GraphPanel;
import java.awt.EventQueue;
import java.awt.GridLayout;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import javax.swing.JSplitPane;

public class SplitGraph extends JPanel {

    public SplitGraph() {
        super(new GridLayout());
        JSplitPane split = new JSplitPane(JSplitPane.VERTICAL_SPLIT);
        GraphPanel graphPanel = new GraphPanel();
        split.setTopComponent(new JScrollPane(graphPanel));
        split.setBottomComponent(graphPanel.getControlPanel());
        this.add(split);
    }

    private void display() {
        JFrame f = new JFrame("SplitGraph");
        f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        f.add(this);
        f.pack();
        f.setLocationRelativeTo(null);
        f.setVisible(true);
    }

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

            @Override
            public void run() {
                new SplitGraph().display();
            }
        });
    }
}

Explanation:

Using pack() automatically adjusts the size of the window to accommodate the preferred sizes of its components. This dynamic calculation ensures that the components resize properly without causing the divider to disappear.

The above is the detailed content of How to Fix Resizing Issues with a Canvas in a JScrollPane within a JSplitPane?. For more information, please follow other related articles on the PHP Chinese website!