发布时间 : 星期六 文章Java习题集3 - 图文更新完毕开始阅读
{
n=n1*n2;
text3.setText(String.valueOf(n)); } else {
n=n1/n2;
text3.setText(String.valueOf(n)); } } }
public class Class1 {
public static void main (String[] args) {
new F3(); } }
8、设计两个文本区和一个?确定?按钮，当在第一个文本区输入文本时，第二个文本区也会显示相同的文本；当点击按钮时，在第二个文本区内会显示?我按了确定按钮?
import java.awt.*;
import java.awt.event.*;
class F4 extends Frame implements TextListener,ActionListener { TextArea text1,text2;Button button; F4()
{ text1=new TextArea(\ text2=new TextArea(\ button=new Button(\确定\
add(text1);add(text2);add(button); text1.addTextListener(this); button.addActionListener(this); setBounds(100,100,400,200); setVisible(true); }
public void textValueChanged(TextEvent e) { if(e.getSource()==text1)
{ text2.setText(text1.getText()); }
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}
public void actionPerformed(ActionEvent e) { if (e.getSource()==button)
text2.setText(\我按了确定按钮\ } }
public class Class1 {
public static void main (String[] args) {
new F4(); } }
9、下图是一程序的运行结果，请编程序完成。
import java.awt.*;
class Mypanel1 extends Panel {
Checkbox box1,box2,box3; Mypanel1() {
box1=new Checkbox(\音乐\ box2=new Checkbox(\体育\ box3=new Checkbox(\吹牛\
add(box1);add(box2);add(box3); } }
class Mypanel2 extends Panel {
Checkbox box1,box2,box3;
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Mypanel2() {
box1=new Checkbox(\读书\ box2=new Checkbox(\电脑\ box3=new Checkbox(\电影\
add(box1);add(box2);add(box3); } }
class F5 extends Frame {
Mypanel1 panel1; Mypanel2 panel2; F5() {
setLayout(new GridLayout(2,2)); panel1=new Mypanel1(); panel2=new Mypanel2();
add(panel1);add(new Label());add(new Label());add(panel2); setBounds(100,100,400,200); setVisible(true); } }
public class Class1 {
public static void main (String[] args) {
new F5(); } }
10、如下图所示，当单击?开南窗?按钮时，出现名字为?阳光窗口?；当单击?开北窗?按钮时，出现名字为?冰雪之窗?的窗口；当单击?关南窗?或?关北窗?按钮时，相应窗口就关闭。
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答：程序如下 import java.awt.*;
import java.awt.event.*;
class Yourwindow extends Frame {
Yourwindow(String s,int a,int b) {
super(s);
setLayout(new GridLayout(1,1)); setSize(a,b);
setBackground(Color.white); setVisible(false); validate(); } }
class F6 extends Frame implements ActionListener {
Yourwindow window1,window2;
Button button1,button2,button3,button4; F6() {
button1=new Button(\开南窗\ button2=new Button(\开北窗\ button3=new Button(\关南窗\ button4=new Button(\关北窗\
window1=new Yourwindow(\阳光之窗\ window2=new Yourwindow(\冰雪之窗\ button1.addActionListener(this); button2.addActionListener(this); button3.addActionListener(this);
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