How to make java.awt.Label background transparent?
I used to do the transparent background with javax.swing.JLabel this way:
开发者_运维知识库lbl.setBackground(new Color(0, 0, 0, 0));
.
But it doesn't work with java.awt.Label. Is there any simple way to make the label transparent?
Update:
public class SplashBackground extends Panel {
private static final long serialVersionUID = 1L;
private Image image = null;
/**
* This is the default constructor
*/
public SplashBackground() {
super();
initialize();
}
/**
* This method initializes this
*
*/
private void initialize() {
image = Toolkit.getDefaultToolkit().createImage(getClass().getResource("/splash/splash.jpg"));
this.setLayout(null);
}
@Override
public void paint(Graphics g) {
super.paint(g);
if(image != null) {
g.drawImage(image, 0,0,this.getWidth(),this.getHeight(),this);
}
}
}
and
lbl= new Label();
lbl.setBackground(new Color(0, 0, 0, 0));
splashBackground = new SplashBackground();
splashBackground.add(appNameLabel, null);
I can see why you do not want to load Swing, since it is for a splash. Sun/Oracle's own implementation of SplashScreen
is AWT all the way.
Why not just use that existing class for your splash functionality?
As mentioned by camickr, see How to Create a Splash Screen for an example.
Now that's what I'm talking about.
As to the labels, leave them out. Use FontMetrics
or (better) TextLayout
to determine the size/position of the text, then just paint it directly to the Image
.
For an example of using the TextLayout
class, see trashgod's answer to 'Java2D Graphics anti-aliased'.
I used to do the transparent background with javax.swing.JLabel this way:
lbl.setBackground(new Color(0, 0, 0, 0));.
That doesn't do anything. A JLabel is transparent by default (ie setOpaque(false)). You may want to read Background With Transparency to understand how tranparency works with Swing.
I've never used a Label but if it works anything like a JLabel, then I would guess you override the isOpaque() method to return false.
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