图形界面程序,窗体背景

编写一个简单的图形界面程序，要求在窗体里显示四个按钮，名称分别为红色、白色、绿色、蓝色，布局管理器设为FlowLayout，要求单击红色按钮，窗体背景显示为红色，点击其它按钮同样。packagecolor;importjava.awt.*;importjava.awt.event.*;publicclassTestFrame{publicstaticvoidmain(Stringargs[]){newMyFrame();}}classMyFrameextendsFrame{Buttonbtn2,btn3,btn4,btn5;MyFrame(){btn2=newButton(红色);btn3=newButton(蓝色);btn4=newButton(绿色);btn5=newButton(白色);setLayout(newFlowLayout());add(btn2);add(btn3);add(btn4);add(btn5);btn2.addActionListener(newColorAct());btn3.addActionListener(newColorAct());btn4.addActionListener(newColorAct());btn5.addActionListener(newColorAct());addWindowListener(newHandleWin());setSize(300,200);setTitle(我的窗口);setVisible(true);}classHandleActimplementsActionListener{Framemy_frame;HandleAct(Framef){my_frame=f;}publicvoidactionPerformed(ActionEvente){my_frame.dispose();System.exit(0);}}classColorActimplementsActionListener{publicvoidactionPerformed(ActionEvente){if(e.getActionCommand()==红色){setBackground(Color.red);setTitle(背景是红色);}elseif(e.getActionCommand()==蓝色){setBackground(Color.blue);setTitle(背景是蓝色);}elseif(e.getActionCommand()==绿色){setBackground(Color.green);setTitle(背景是绿色);}elseif(e.getActionCommand()==白色){setBackground(Color.white);setTitle(背景是白色);}}}classHandleWinextendsWindowAdapter{publicvoidwindowClosing(WindowEvente){(e.getWindow()).dispose();System.exit(0);}}}