guidraw.java

Java课程中所有的可运行程序 全部都是java课程中所涉及到的源码

import java.applet.*;
import java.awt.*;
import java.awt.event.*;

 public class guidraw extends Applet{
public void init() {

 label1=new Label("radius:");
 add(label1);
 edit1=new Scrollbar(Scrollbar.HORIZONTAL,0,20,0,200);
 edit1.addAdjustmentListener(new AdjustmentListener(){
  public void adjustmentValueChanged(AdjustmentEvent e){
  changeradius(e);}
});
 add(edit1);

 label4=new Label();
 add(label4);

 label2=new Label("color:");
 add(label2);
 choice1= new Choice();
 add(choice1);
choice1.addItem("red");
 choice1.addItem("blue");
 choice1.addItem("green");
 choice1.addItem("yellw");
 choice1.addItem("black");
choice1.addItemListener(new ItemListener(){
 public void itemStateChanged(ItemEvent e){
 changecolor(e);}
});


 label3=new Label("mode:");
 add(label3);
 group1= new CheckboxGroup();
 check1=new Checkbox("fill",group1, true);
check1.addItemListener(new ItemListener(){
 public void itemStateChanged(ItemEvent e){
  changemode(e);}
});
 add(check1);
 check2=new Checkbox("draw",group1, false);
 check2.addItemListener(new ItemListener(){
  public void itemStateChanged(ItemEvent e){
 changemode(e);}
});
 add(check2);

  button1=new Button("cacel");
  button1.addActionListener(new ActionListener(){
           public void actionPerformed(ActionEvent e){
                cacel(e);}
                  }  );
 add(button1);

}



 CheckboxGroup group1;
 Scrollbar edit1;
 Label label1;
 Choice choice1;
 Checkbox check1;
 Checkbox check2;
 Button button1;
 Label label2;
 Label label3,label4;
 int mode;
 Color color=Color.red;
 int radius;

 //}}

 public void changecolor(ItemEvent e) {

int nowcolor=choice1.getSelectedIndex();
switch(nowcolor){
case 0:{color=Color.red;break;}
case 1:{color=Color.blue;break;}
case 2:{color=Color.green;break;}
case 3:{color=Color.yellow;break;}
case 4:{color=Color.black;break;}
}
repaint();

    // to do: put event handler code here.
}


public void paint(Graphics g){
if(mode==-1){
    g.setColor(Color.white);
    g.fillOval(80,100,200 ,200);
}

  if(mode==0){
   g.setColor(color);
         g.fillOval(80,100,radius ,radius);}

    if(mode==1){
            g.setColor(color);
         g.drawOval(80,100,radius ,radius);}

	}


protected void  cacel(ActionEvent e){

mode=-1;
repaint();
mode=0;
check1.setState(true);
check2.setState(false);
color=Color.red;
choice1.select(0);
radius=0;
edit1.setValue(0);
label4.setText("");
}


public void  changemode(ItemEvent e){
     String name=(String)e.getItem();
 if (name=="fill"){
	if (e.getStateChange()==e.SELECTED)
		mode=0;}
if (name=="draw"){
	if (e.getStateChange()==e.SELECTED)
		mode=1;}
		repaint();
 }


 public void  changeradius(AdjustmentEvent e){
 radius=e.getValue();
 String ss="";
 label4.setText(ss.valueOf(radius));
repaint();
}

}