Question

I am trying to create a Swing panel whose elements have a different font size than the rest of the swing application. Initially, using setFont for a couple of components didn’t pose any problems. Now I have several components (and all their subcomponents), so this solution is impractical.

I have searched about changing the default UI properties of swing components. What I have found is mostly using the UIManager, which changes the properties globally. This doesn’t work for me because I want to keep the current font settings for all the other panels.

For the moment (and since I don’t like to post without trying something out first), I have an algorithm like this:

public static void fixFont(Container c) {
    c.setFont(c.getFont().deriveFont(10.0f));
    Component[] comp = c.getComponents();
    for (int i=0;i<comp.length;++i) {
        if (comp[i] instanceof Container) {
            fixFont((Container) comp[i]);
        } else {
            comp[i].setFont(comp[i].getFont().deriveFont(10.0f));
        }
    }
}

The problem is that:

• it doesn’t include certain swing elements like its border.
• I have to call this function when I add other components dynamically

Question: Is there another way to change the font properties of a Swing panel and all its components, elements, etc (i.e. everything in the panel) ?

Thanks for your ideas

Answer 1

You could use this trick:

import java.awt.*;

public class FrameTest {

    public static void setUIFont(FontUIResource f) {
        Enumeration keys = UIManager.getDefaults().keys();
        while (keys.hasMoreElements()) {
            Object key = keys.nextElement();
            Object value = UIManager.get(key);
            if (value instanceof FontUIResource) {
                FontUIResource orig = (FontUIResource) value;
                Font font = new Font(f.getFontName(), orig.getStyle(), f.getSize());
                UIManager.put(key, new FontUIResource(font));
            }
        }
    }

    public static void main(String[] args) throws InterruptedException {

        setUIFont(new FontUIResource(new Font("Arial", 0, 20)));

        JFrame f = new JFrame("Demo");
        f.getContentPane().setLayout(new BorderLayout());

        JPanel p = new JPanel();
        p.add(new JLabel("hello"));
        p.setBorder(BorderFactory.createTitledBorder("Test Title"));

        f.add(p);

        f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        f.setSize(300, 300);
        f.setVisible(true);
    }
}

Produces: