package g;import java.awt.*;import java.awt.event.*;import java.applet.*;/*<applet code="ButtonDemo"width =250 height=150></applet>... 展开
package g;import java.awt.*;import java.awt.event.*;import java.applet.*;/*<applet code="ButtonDemo"width =250 height=150></applet>*/ public class ButtonDemo extends Applet implements ActionListener{ String msg = "";Button yes, no ,maybe;public void init(){ yes = new Button("Yes");no = new Button("No");maybe = new Button("Undecided");add(yes);add(no);add(maybe);yes.addActionListener(this);no.addActionListener(this);maybe.addActionListener(this);} public void actionPerformed(ActionEvent ae){ String str = ae.getActionCommand();if(str.equals(yes)){ msg = "You pressed Yes.";} else if(str.equals(no)){ msg = "You pressed No.";} else if(str.equals(maybe)){ msg = "You pressed meybe.";} repaint();} public void paint(Graphics g){ g.drawString(msg, 6, 100);} } 收起