package Widget;

import java.awt.AlphaComposite;

import java.awt.Color;

import java.awt.Graphics;

import java.awt.Graphics2D;

import javax.swing.Icon;

import javax.swing.JLabel;

public class AlphaLabel extends JLabel{

private float alpha = 0.4f;

private Color alphaColor;

public AlphaLabel(){

super();

}

public AlphaLabel(String text) {

super(text);

}

public AlphaLabel(Icon icon){

super(icon);

}

public void setAlpha(float alpha){

this.alpha = alpha;

this.invalidate();

}

public void setAlphaColor(Color alphaColor){

this.alphaColor = alphaColor;

}

@Override

protected void paintComponent(Graphics g) {

// TODO Auto-generated method stub

super.paintComponent(g);

Graphics2D g2 = (Graphics2D)g;

//设置透明度为0.4f

AlphaComposite ac = AlphaComposite.getInstance(AlphaComposite.SRC_OVER, alpha);

g2.setComposite(ac);

alphaColor = (alphaColor == null) ? Color.WHITE : alphaColor;

g2.setColor(alphaColor);

//绘制一个与输入域等大小的填充矩形框来形成其半透明效果

g2.fillRect(0, 0, getWidth(), getHeight());

}

}