12.5.2 Image的内部机制

p { margin-bottom: 0.21cm; }

Image对象在最小化时会

• 将Image方法存储到缓存中我们这样能方便我们做重绘操作

• 自动调用paint()方法 所以我们不需要手动调用或用rePaint方法调用

编程实例 将一张图片显示出来

publicclassDrawImage extendsFrame {

Imageimg= getToolkit().getImage("src/cn/itcast/guis/log.jpg");

@Override

publicvoidpaint(Graphics g) {

//TODOAuto-generated method stub

super.paint(g);

g.drawImage(img,0,0,this);

}

publicDrawImage() {

//TODOAuto-generated constructor stub

addWindowListener(newWindowAdapter(){

//内部匿名类定义一个window事件适配器关闭窗体

@Override

publicvoidwindowClosing(WindowEvent e) {

//TODOAuto-generated method stub

super.windowClosing(e);

e.getWindow().dispose();

System.exit(0);

}

});

}

publicstaticvoidmain(String[] args) {

DrawImagedraImg = newDrawImage();

draImg.setSize(400,400);

draImg.setVisible(true);

}

}