经典代码收藏之——百叶窗特效的Java实现

import javax.swing.*;
import java.awt.*;
import java.awt.Event;
import javax.swing.event.*;
import java.awt.image.BufferedImage;

class TransitionTabbedPane extends JTabbedPane
implements ChangeListener, Runnable{
protected int animation_length=20;
public TransitionTabbedPane(){
super();
this.addChangeListener(this);

}

public int getAnimationLength(){
return this.animation_length;
}
public void setAnimationLength(int length)
{
this.animation_length=length;
}

public void stateChanged(ChangeEvent evt)
{
new Thread(this).start();
}

protected int step;
protected BufferedImage buf=null;
protected int previous_tab=-1;
public void run(){
step=0;

if(this.previous_tab!=-1)
{
   Component comp=this.getComponentAt(this.previous_tab);
   this.buf=new BufferedImage(comp.getWidth(),comp.getHeight(),
     BufferedImage.TYPE_4BYTE_ABGR);
   comp.paint(buf.getGraphics());
}

for(int i=0;i<this.animation_length;i++)
{
   step=i;
   repaint();
   try{
    Thread.currentThread().sleep(100);
   }
   catch(Exception ex)
   {
    System.out.println(""+ex.toString());
   }
  
}

step=-1;
this.previous_tab=this.getSelectedIndex();
repaint();
}

public void paintChildren(Graphics g)
{
super.paintChildren(g);

if(step!=-1)
{
   Rectangle size=this.getComponentAt(0).getBounds();
   Graphics2D g2=(Graphics2D)g;
   paintTransition(g2,step,size,buf);
}
}

public void paintTransition(Graphics2D g2,int step,
   Rectangle size,Image prev){

}
}

class InOutPane extends TransitionTabbedPane {
public void paintTransition(Graphics2D g2, int state,
   Rectangle size, Image prev) {

int length = getAnimationLength();
int half = length/2;
double scale = size.getHeight()/length;
int offset = 0;
// calculate the fade out part
if(state >= 0 && state < half) {
//draw the saved version of the old tab component
if(prev != null) {
   g2.drawImage(prev,(int)size.getX(),(int)size.getY(),null);
}
offset = (int)((10-state)*scale);
}
// calculate the fade in part
if(state >= half && state < length) {
g2.setColor(Color.white);
offset = (int)((state-10)*scale);

}

// do the drawing
g2.setColor(Color.white);
Rectangle area = new Rectangle((int)(size.getX()+offset),

(int)(size.getY()+offset),
(int)(size.getWidth()-offset*2),
(int)(size.getHeight()-offset*2));

g2.fill(area);
}
}

public class TabFadeTest {
public static void main(String[] args) {
   JFrame frame = new JFrame("Fade Tabs");
//JTabbedPane tab = new InOutPane();
         JTabbedPane tab=new VenetianPane();
   tab.addTab("t1",new JButton("Test Button 1"));
   tab.addTab("t2",new JButton("Test Button 2"));

   frame.getContentPane().add(tab);
   frame.pack();
   frame.setVisible(true);

   }
}

class VenetianPane extends TransitionTabbedPane {
public void paintTransition(Graphics2D g2, int step,
    Rectangle size, Image prev) {
   int length = getAnimationLength();
   int half = length/2;

   // create a blind
   Rectangle blind = new Rectangle();

   // calculate the fade out part
   if(step >= 0 && step < half) {
    // draw the saved version of the old tab component
    if(prev != null) {

    g2.drawImage(prev,(int)size.getX(),(int)size.getY(),null);
    }
    // calculate the growing blind
    blind = new Rectangle(
    (int)size.getX(),
    (int)size.getY(),
    step,
    (int)size.getHeight());

   }
   // calculate the fade in part
   if(step >= half && step < length) {
    // calculate the shrinking blind
    blind = new Rectangle(

    (int)size.getX(),
    (int)size.getY(),
    length-step,
    (int)size.getHeight());

    blind.translate(step-half,0);
   }

   // draw the blinds
   for(int i=0; i<size.getWidth()/half; i++) {
    g2.setColor(Color.white);
    g2.fill(blind);
    blind.translate(half,0);

    }
   }
}