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#2
林月儿2017-07-12 10:02
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import java.applet.*;
import javax.swing.*;
class MyPanel extends JPanel{
JButton button1,button2;
JLable lable;
MyPanel(String s1, String s2, String s3){
button1 = new JButton(s1);button2 = new JButton(s2);
lable = new JLable(s3);
add(button1);add(button2);add(lable);
}
}
public class example extends Applet {
MyPanel panel1,panel2;
JButton button;
public void init(){
panel1 = new MyPanel("ok","cancel","this is the lable in the first panel.");
panel2 = new MyPanel("ok","cancel","this is the lable in the second panel.");
button = new JButton("this is the button that do not belong to any panel");
add(panel1);add(panel2);add(button);
setSize(300, 200);
}
}
编译命令:javac example.javaimport javax.swing.*;
class MyPanel extends JPanel{
JButton button1,button2;
JLable lable;
MyPanel(String s1, String s2, String s3){
button1 = new JButton(s1);button2 = new JButton(s2);
lable = new JLable(s3);
add(button1);add(button2);add(lable);
}
}
public class example extends Applet {
MyPanel panel1,panel2;
JButton button;
public void init(){
panel1 = new MyPanel("ok","cancel","this is the lable in the first panel.");
panel2 = new MyPanel("ok","cancel","this is the lable in the second panel.");
button = new JButton("this is the button that do not belong to any panel");
add(panel1);add(panel2);add(button);
setSize(300, 200);
}
}
结果:example.java:8: error: cannot find symbol
JLable lable;
^
symbol: class JLable
location: class MyPanel
example.java:11: error: cannot find symbol
lable = new JLable(s3);
^
symbol: class JLable
location: class MyPanel
2 errors
[此贴子已经被作者于2017-7-12 10:03编辑过]