The code is the same as the example, but here it goes
TestJLayerZoom.java
import java.awt.Dimension;
import java.awt.EventQueue;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.JButton;
import javax.swing.JComponent;
import javax.swing.JFrame;
import javax.swing.JLayer;
import javax.swing.JPanel;
import javax.swing.WindowConstants;
public class TestJLayerZoom {
public static void main(String args[]) {
EventQueue.invokeLater(new Runnable() {
@Override
public void run() {
JFrame frame = new JFrame();
frame.setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);
JPanel panel = new JPanel();
ZoomUI layerUI = new ZoomUI();
JLayer<JComponent> jLayer = new JLayer<JComponent>(panel, layerUI);
JButton zoomIn = new JButton("Zoom In");
zoomIn.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
layerUI.zoom += 0.1;
jLayer.revalidate();
jLayer.repaint();
}
});
panel.add(zoomIn);
JButton zoomOut = new JButton("Zoom Out");
zoomOut.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
layerUI.zoom -= 0.1;
jLayer.revalidate();
jLayer.repaint();
}
});
panel.add(zoomOut);
frame.setPreferredSize(new Dimension(400, 200));
frame.add(jLayer);
frame.pack();
frame.setVisible(true);
}
});
}
}
ZoomUI.java
import java.awt.AWTEvent;
import java.awt.Graphics;
import java.awt.Graphics2D;
import javax.swing.JComponent;
import javax.swing.JLayer;
import javax.swing.plaf.LayerUI;
public class ZoomUI extends LayerUI<JComponent> {
public double zoom = 1; // Changing this value seems to have no effect
@Override
public void paint(Graphics g, JComponent c) {
Graphics2D g2 = (Graphics2D) g.create();
g2.scale(zoom, zoom);
super.paint(g2, c);
g2.dispose();
}
@Override
public void installUI(JComponent c) {
super.installUI(c);
JLayer jlayer = (JLayer) c;
jlayer.setLayerEventMask(
AWTEvent.MOUSE_EVENT_MASK | AWTEvent.ACTION_EVENT_MASK
| AWTEvent.MOUSE_MOTION_EVENT_MASK
);
}
@Override
public void uninstallUI(JComponent c) {
JLayer jlayer = (JLayer) c;
jlayer.setLayerEventMask(0);
super.uninstallUI(c);
}
}
In the image I explain the problem