Author: Zafir Anjum
Rotate the JLabel by 90 degrees either clockwise or anti-clockwise. Works on JDK 1.2+.
A new subclass of BasicLabelUI is created to handle the proper dimensions and rendering. The Graphics2D class is used to handle the rendering.
import java.awt.*;
import java.util.*;
import java.awt.event.*;
import javax.swing.*;
import javax.swing.border.*;
import javax.swing.plaf.basic.*;
import java.awt.geom.*;
// This code uses Graphics2D which is supported only on Java 2
public class Main
{
public static void main(String[] args)
{
JFrame frame = new JFrame("Main");
frame.addWindowListener( new WindowAdapter() {
public void windowClosing(WindowEvent e)
{
Window win = e.getWindow();
win.setVisible(false);
win.dispose();
System.exit(0);
}
} );
frame.getContentPane().setLayout( new FlowLayout() );
ImageIcon icon = new ImageIcon( "dukeWave.gif" ) ;
JLabel l = new JLabel( "Rotated anti-clockwise", icon, SwingConstants.LEFT );
l.setUI( new VerticalLabelUI(false) );
l.setBorder( new EtchedBorder() );
frame.getContentPane().add( l );
l = new JLabel( "Rotated Clockwise", icon, SwingConstants.LEFT );
// l.setHorizontalTextPosition( SwingConstants.LEFT );
l.setUI( new VerticalLabelUI(true) );
l.setBorder( new EtchedBorder() );
frame.getContentPane().add( l );
frame.getContentPane().add( new JButton( "Button" ) );
frame.pack();
frame.show();
}
}
class VerticalLabelUI extends BasicLabelUI
{
static {
labelUI = new VerticalLabelUI(false);
}
protected boolean clockwise;
VerticalLabelUI( boolean clockwise )
{
super();
this.clockwise = clockwise;
}
public Dimension getPreferredSize(JComponent c)
{
Dimension dim = super.getPreferredSize(c);
return new Dimension( dim.height, dim.width );
}
private static Rectangle paintIconR = new Rectangle();
private static Rectangle paintTextR = new Rectangle();
private static Rectangle paintViewR = new Rectangle();
private static Insets paintViewInsets = new Insets(0, 0, 0, 0);
public void paint(Graphics g, JComponent c)
{
JLabel label = (JLabel)c;
String text = label.getText();
Icon icon = (label.isEnabled()) ? label.getIcon() : label.getDisabledIcon();
if ((icon == null) && (text == null)) {
return;
}
FontMetrics fm = g.getFontMetrics();
paintViewInsets = c.getInsets(paintViewInsets);
paintViewR.x = paintViewInsets.left;
paintViewR.y = paintViewInsets.top;
// Use inverted height & width
paintViewR.height = c.getWidth() - (paintViewInsets.left + paintViewInsets.right);
paintViewR.width = c.getHeight() - (paintViewInsets.top + paintViewInsets.bottom);
paintIconR.x = paintIconR.y = paintIconR.width = paintIconR.height = 0;
paintTextR.x = paintTextR.y = paintTextR.width = paintTextR.height = 0;
String clippedText =
layoutCL(label, fm, text, icon, paintViewR, paintIconR, paintTextR);
Graphics2D g2 = (Graphics2D) g;
AffineTransform tr = g2.getTransform();
if( clockwise )
{
g2.rotate( Math.PI / 2 );
g2.translate( 0, - c.getWidth() );
}
else
{
g2.rotate( - Math.PI / 2 );
g2.translate( - c.getHeight(), 0 );
}
if (icon != null) {
icon.paintIcon(c, g, paintIconR.x, paintIconR.y);
}
if (text != null) {
int textX = paintTextR.x;
int textY = paintTextR.y + fm.getAscent();
if (label.isEnabled()) {
paintEnabledText(label, g, clippedText, textX, textY);
}
else {
paintDisabledText(label, g, clippedText, textX, textY);
}
}
g2.setTransform( tr );
}
}
Posted On: 14-Feb-1999