请教个问题.

Question

JTextField tx1=new JtextField(10);
JTextField tx2=new JtextField(10);
JButton bt1=new JButton("a");
....
bt1.addActionListener(al);
ActionListener al=new ActionListener()
{
.....(event e)
{
/*
这里想用tx1.getText()然后把字符串转化成数组,进行一个算法if(e.getSource()==bt1).....;,然后再转回String在tx2.setText()显示出来.
用到getChars()与String.valueOf();ECLIPSE检查语法没错误.运行后点bt1会报异常.大概意思好象是UNKNOW SOURCE
*/
}};代码暂时发不上来.请问这是什么问题?

Answer 1

//源码是这个...可能写的比较菜.请指教.异常写在下一帖.package test2;
import javax.swing.*;
import java.awt.event.*;
public class IoGUI extends JFrame{
JPanel pane;
JButton button1,button2;
JTextField text1,text2;
JLabel title;
String str="C:\\Documents and Settings\\桌面\\PIC\\";
IoGUI()
{super();
pane=new JPanel();
this.getContentPane().add(pane);
title=new JLabel(new ImageIcon(str+"sister.jpg"));
text1=new JTextField(10);
text2=new JTextField(10);
button1=new JButton("计算");
button2=new JButton("concel");
ActionListener al=new ActionListener()
{
public void actionPerformed(ActionEvent e) {
if(e.getSource()==button1){
String in= text1.getText
if(in==null) JOptionPane.showMessageDialog(null,"Please in put");

int len=in.length();
char ch[]=new char[len];
char si[]=new char[100];
si[0]=ch[0];
in.getChars(0,len,ch,0);
while(ch[len-1]!='\0')
{if(ch[len]==si[0])
{ch[len]='A'; 
break;}
else if(len==0)break;
else len-=1;
}



String string=String.valueOf(ch);
text2.setText(string);
}
if(e.getSource()==button2)JOptionPane.showMessageDialog(null,"Good bye");
System.exit(0);
}

};
button1.addActionListener(al);
button2.addActionListener(al);
pane.add(title);
pane.add(text1);pane.add(text2);
pane.add(button1);pane.add(button2);
setVisible(true);
setSize(700,600);
setLocation(200,200);
setResizable(false);
}
public static void main(String[] args) {
new IoGUI(); }}

Answer 2

Exception in thread "AWT-EventQueue-0" java.lang.ArrayIndexOutOfBoundsException: 5
at test2.IoGUI$1.actionPerformed(IoGUI.java:32)
at javax.swing.AbstractButton.fireActionPerformed(Unknown Source)
at javax.swing.AbstractButton$Handler.actionPerformed(Unknown Source)
at javax.swing.DefaultButtonModel.fireActionPerformed(Unknown Source)
at javax.swing.DefaultButtonModel.setPressed(Unknown Source)
at javax.swing.plaf.basic.BasicButtonListener.mouseReleased(Unknown Source)
at java.awt.Component.processMouseEvent(Unknown Source)
at javax.swing.JComponent.processMouseEvent(Unknown Source)
at java.awt.Component.processEvent(Unknown Source)
at java.awt.Container.processEvent(Unknown Source)
at java.awt.Component.dispatchEventImpl(Unknown Source)
at java.awt.Container.dispatchEventImpl(Unknown Source)
at java.awt.Component.dispatchEvent(Unknown Source)
at java.awt.LightweightDispatcher.retargetMouseEvent(Unknown Source)
at java.awt.LightweightDispatcher.processMouseEvent(Unknown Source)
at java.awt.LightweightDispatcher.dispatchEvent(Unknown Source)
at java.awt.Container.dispatchEventImpl(Unknown Source)
at java.awt.Window.dispatchEventImpl(Unknown Source)
at java.awt.Component.dispatchEvent(Unknown Source)
at java.awt.EventQueue.dispatchEvent(Unknown Source)
at java.awt.EventDispatchThread.pumpOneEventForFilters(Unknown Source)
at java.awt.EventDispatchThread.pumpEventsForFilter(Unknown Source)
at java.awt.EventDispatchThread.pumpEventsForHierarchy(Unknown Source)
at java.awt.EventDispatchThread.pumpEvents(Unknown Source)
at java.awt.EventDispatchThread.pumpEvents(Unknown Source)
at java.awt.EventDispatchThread.run(Unknown Source)

Answer 3

if(e.getSource()==button1){
String   in=   text1.getText
if(in==null)   JOptionPane.showMessageDialog(null,"Please   in   put"); 这里有点小错误
然后运行程序没有报异常，不过就出现一个panel，上面什么都没有，应该不是楼主期待的，
所以楼主的代码的界面还没做好
界面做好再加上事件吧。

Answer 4

while(ch[len-1]!='\0') 
{if(ch[len]==si[0]) 
{ch[len]='A';   
break;} 
else   if(len==0)break; 
else   len-=1; 
} 越界了
改成这样
import   javax.swing.*;
import java.awt.*;
import   java.awt.event.*; 
public   class   Test   extends   JFrame{ 
JPanel   pane; 
JButton   button1,button2; 
JTextField   text1,text2; 
JLabel   title; 
String   str="C:\\Documents   and   Settings\\桌面\\PIC\\"; 
Test() 
{super(); 
pane=new   JPanel(); 
Container con=getContentPane();
title=new   JLabel(new   ImageIcon(str+"sister.jpg")); 
text1=new   JTextField(10); 
text2=new   JTextField(10); 
button1=new   JButton("计算"); 
button2=new   JButton("concel"); ActionListener   al=new   ActionListener() 
{ 
public   void   actionPerformed(ActionEvent   e)   { 
if(e.getSource()==button1){ 
String   in=   text1.getText() ;
if(in==null)   JOptionPane.showMessageDialog(null,"Please   in   put"); int   len=in.length(); 
char   ch[]=in.toCharArray();char   si[]=new   char[len]; 
si[0]=ch[0]; 
in.getChars(0,len,ch,0); 
while(ch[len-1]!='\0') 
{if(ch[len-1]==si[0]) 
{ch[len-1]='A';   
break;} 
else   if(len==0)break; 
else   len-=1; 
} String   string=String.valueOf(ch); 
text2.setText(string); 
} 
if(e.getSource()==button2)
{
JOptionPane.showMessageDialog(null,"Good   bye"); 
    System.exit(0);
}
} }; 
button1.addActionListener(al); 
button2.addActionListener(al); 
pane.add(title); 
pane.add(text1);pane.add(text2); 
pane.add(button1);pane.add(button2); 
 con.add(pane); 
setSize(700,600); 
setLocation(200,200); 
setResizable(false); 
setVisible(true);
} 
public   static   void   main(String[]   args)   { 
new   Test(); } }

Answer 5

是超了．但是好象不是我这个异常吧．
现在在别人的机器上。调不了．．．
６楼能解释下么？我这里都能出来．有图片ＢＵＴＴＯＮ，和ＴＥＸＴ．
点button1就显示有异常．