Java程序设计——12图形绘制PPT课件.ppt

计算机科学与技术学院
赵志崑
[e-mail]在组件上绘制图形paintComponent方法绘制直线绘制矩形绘制圆角矩形绘制椭圆绘制弧线绘制多边形设置颜色输出文字设置字体见ImageExample.java
classImagePanelextendsJPanel{
privateImageunitsImage=null;
privateintunitX;
privateintunitY;
publicImagePanel(){
Toolkitkit=Toolkit.getDefaultToolkit();
unitsImage=kit.getImage("globe.gif");
}
publicvoidpaintComponent(Graphicsg){
super.paintComponent(g);
g.drawRect(10,10,100,100);
g.drawImage(unitsImage,unitX,unitY,null);
}
publicvoidsetUnitLocation(intaX,intaY){
unitX=aX;
unitY=aY;
repaint();
}
}见ImageExample1.java
publicvoidpaintComponent(Graphicsg){
……
intsx1=118*unitIndex;
intsy1=0;
intsx2=sx1+117;
intsy2=sy1+97;
intdx1=unitX;
intdy1=unitY;
intdx2=dx1+117;
intdy2=dy1+97;
g.drawImage(unitsImage,dx1,dy1,dx2,dy2,sx1,sy1,sx2,sy2,null);
}
publicvoidsetUnitLocation(intaX,intaY){
……
unitIndex=(unitIndex+1)%4;
repaint();
}等待图像加载Java支持的图片格式Graphics2D缓冲区绘图见DoubleBufferExample.java
classPhotoPanelextendsJPanel
{privateBufferedImagebackImage=newBufferedImage(1024,800,
BufferedImage.TYPE_BYTE_INDEXED);
publicvoidpaintComponent(Graphicsg)
{ super.paintComponent(g);
GraphicsbackG=backImage.getGraphics();
backG.drawImage(photoImage,0,0,null);
g.drawImage(backImage,0,0,null);
backG.dispose();
}
publicColorgetColor(intx,inty)
{ intc=backImage.getRGB(x,y);
returnnewColor(c);
}
}将图片保存到文件感谢!