Java期末复习题全(3)

分析程序输出结果 5-1 Exer5_1.java import java.applet.*; import java.awt.*;

public class Exer5_1 extends Applet { private Label lab1,lab2; public void init() { lab1=new Label(); lab1.setText(\标签文本左对齐\ lab1.setAlignment(Label.LEFT); lab2=new Label(\标签文本右对齐\ setLayout(new GridLayout(3,3)); add(lab1);add(lab2);

} }

运行改程序后，输出结果如图5-5所示。

图5-5 分析题5-1输出结果 5-2 Exer5_2.java import java.applet.*; import java.awt.*;

import java.awt.event.*;

public class Exer5_2 extends Applet implements ActionListener,ItemListener { List colList; String colName[]={\黑色\蓝色\浅蓝色\绿色\红色\黄色\ Color cols[]={Color.black,Color.blue,Color.cyan,Color.green,Color.red,Color.yellow}; int t; public void init() {

colList=new List(4,false);

colList.addActionListener(this); colList.addItemListener(this); for(int i=0;i

11

colList.add(colName[i]); add(colList);

}

public void actionPerformed(ActionEvent e) {}

public void itemStateChanged(ItemEvent e) { showStatus(colList.getSelectedItem()+\ t=colList.getSelectedIndex(); repaint(); }

public void paint(Graphics g) { g.setColor(cols[t]); g.fillRect(15,30,20,20); }

}

运行改程序后，输出结果如图5-6所示。

5-3 Exer5_3.java import java.awt.*;

import java.awt.event.*;

public class Exer5_3 extends Frame implements ActionListener { Frame fr; Panel deck; CardLayout c1; Button but[]; String name[]={\第一张\下一张\前一张\最末张\ public Exer5_3() { fr=new Frame(\卡片窗口\ deck=new Panel(); c1=new CardLayout(); deck.setLayout(c1); Panel c1=new Panel(); Label lab1=new Label(\卡片1\

12

c1.add(lab1);

deck.add(c1,lab1.getText()); Panel c2=new Panel();

Label lab2=new Label(\卡片2\ c2.add(lab2);

deck.add(c2,lab2.getText()); Panel c3=new Panel();

Label lab3=new Label(\卡片3\ c3.add(lab3);

deck.add(c3,lab3.getText()); Panel c4=new Panel();

Label lab4=new Label(\卡片4\ c4.add(lab4);

deck.add(c4,lab4.getText());

Panel contr=new Panel();

contr.setLayout(new GridLayout(2,2)); but=new Button[name.length]; for(int i=0;i

contr.add(but[i]); }

fr.add(contr,BorderLayout.WEST); fr.add(deck,BorderLayout.EAST); fr.setSize(300,150); fr.show();

}

public void actionPerformed(ActionEvent e) { if(e.getSource()==but[0]) c1.first(deck); if(e.getSource()==but[1]) c1.next(deck); if(e.getSource()==but[2]) c1.previous(deck); if(e.getSource()==but[3]) c1.last(deck); }

public static void main(String args[]) { Exer5_3 m1=new Exer5_3(); }

13

}

运行该程序后，输出结果如图5-7所示。

5-4 Exer5_4.java import java.awt.*;

public class Exer5_4 extends Frame { TextField tf=new TextField(\ MenuBar mb1=new MenuBar(); Menu f=new Menu(\文件\ Menu m=new Menu(\照片\ Menu s=new Menu(\储存\ String name[]={\第一张\下一张\前一张\最末张\ CheckboxMenuItem[]save={new CheckboxMenuItem(\保存\另存为\ MenuItem[] file1={new MenuItem(\打开\关闭\ MenuBar mb2=new MenuBar(); Menu fo=new Menu(\水果\ MenuItem[] fruit={new MenuItem(\香蕉\苹果\李子\ Button but=new Button(\ public Exer5_4() { for(int i=0;i

}

for(int i=0;i

s.add(save[i]);

f.add(s);

for(int i=0;i

f.add(file1[i]);

mb1.add(f); mb1.add(m);

setMenuBar(mb1); tf.setEditable(false); add(\add(\

for(int i=0;i

fo.add(fruit[i]);

14

mb2.add(fo); }

public boolean handleEvent(Event e) { if(e.id==Event.WINDOW_DESTROY) System.exit(0); else return super.handleEvent(e); return true; }

public boolean action(Event e,Object arg) { if(e.target.equals(but)) { MenuBar m=getMenuBar(); if(m==mb1) setMenuBar(mb2); else if(m==mb2) setMenuBar(mb1); }

else if(e.target instanceof MenuItem) { if(arg.equals(\打开\ { String str=tf.getText(); Boolean ch=false; for(int i=0;i

else if(e.target.equals(file1[1])) System.exit(0);

else if(e.target.equals(save[0])) tf.setText(\你按了保存菜单\else if(e.target.equals(save[1])) tf.setText(\你按了另存为菜单\else tf.setText(arg.toString()); } else return super.action(e,arg); return true; }

15

百度搜索“77cn”或“免费范文网”即可找到本站免费阅读全部范文。收藏本站方便下次阅读，免费范文网，提供经典小说综合文库Java期末复习题全(3)在线全文阅读。