txt6.addFocusListener(new FocusAdapter(){
public void focusGained(FocusEvent e){
txt6.setText("");}
public void focusLost(FocusEvent e){
final String str2=txt6.getText();
final char ch2[]=str2.toCharArray();
txt7.setText(ch2[3]);
txt8.setText(ch2[2]);}
}); txt6和txt7、txt8都是已经定义好的文本框,现在给txt6添加事件。
txt7.setText(ch2[3]);这里面提示说找不到符号,而txt6.setText("");则正确的。搞不明白啊
你给的描述太模糊了
import javax.swing.*;
import java.awt.event.*;public class sum7 {
static JFrame frm=new JFrame("四位加法器"); static TextField txt1=new TextField("加数Q1",4);
static TextField txt6=new TextField("加数Q2",4);
static TextField txt2=new TextField("",1);
static TextField txt3=new TextField("",1);
static TextField txt4=new TextField("",1);
static TextField txt5=new TextField("",1);
static TextField txt7=new TextField("",1);
static TextField txt8=new TextField("",1);
static TextField txt9=new TextField("",1);
static TextField txt10=new TextField("",1);
static TextField txt11=new TextField("",1);
static TextField txt12=new TextField("",1);
static TextField txt13=new TextField("",1);
static TextField txt14=new TextField("",1);
static TextField txt15=new TextField("",1);
static TextField txt16=new TextField("",1);
static TextField txt17=new TextField("",1);
static TextField txt18=new TextField("",1);
static TextField txt19=new TextField("",1);
static TextField txt20=new TextField("",1);
static TextField txt21=new TextField("",1);
static TextField txt22=new TextField("",1);
static TextArea txtr=new TextArea(); public static void main(String args[]){
frm.setSize(700,430);
frm.setLayout(null);
//frm.setOpaque(false);
frm.setBackground(Color.gray);
//以下设置文本框
txt1.setBounds(40,40,60,30);
txt6.setBounds(40,130,60,30);
txt2.setBounds(200,40,60,30);
txt2.setEditable(false);
txt3.setBounds(260,40,60,30);
txt3.setEditable(false);
txt4.setBounds(320,40,60,30);
txt4.setEditable(false);
txt5.setBounds(380,40,60,30);
txt5.setEditable(false);
txt7.setBounds(200,130,60,30);
txt7.setEditable(false);
txt8.setBounds(260,130,60,30);
txt8.setEditable(false);
txt9.setBounds(320,130,60,30);
txt9.setEditable(false);
txt10.setBounds(380,130,60,30);
txt10.setEditable(false);
txt11.setBounds(40,220,60,30);
txt11.setText("进位Ci");
txt11.setEditable(false);
txt12.setBounds(150,220,50,30);
txt12.setEditable(false);
txt13.setBounds(200,220,60,30);
txt13.setEditable(false);
txt14.setBounds(260,220,60,30);
txt14.setEditable(false);
txt15.setBounds(320,220,60,30);
txt15.setEditable(false);
txt16.setBounds(380,220,60,30);
txt16.setText("C0=0");
txt16.setEditable(false);
txt17.setBounds(40,310,60,30);
txt17.setEditable(false);
txt18.setBounds(150,310,50,30);
txt18.setEditable(false);
txt19.setBounds(200,310,60,30);
txt19.setEditable(false);
txt20.setBounds(260,310,60,30);
txt20.setEditable(false);
txt21.setBounds(320,310,60,30);
txt21.setEditable(false);
txt22.setBounds(380,310,60,30);
txt22.setEditable(false);
txtr.setBounds(460,40,230,310);
txtr.setEditable(false);
//以下添加文本框
frm.add(txt1);
frm.add(txt6);
Font font=new Font("楷体",Font.BOLD,16);
txt1.setFont(font);
txt6.setFont(font);
final String str1=txt1.getText();
final String str2=txt6.getText();
final char ch1[]=str1.toCharArray();
final char ch2[]=str2.toCharArray();
frm.add(txt2);
txt2.setFont(font);
//txt2.setText(ch[3]);
frm.add(txt3);
txt3.setFont(font);
//txt3.setText(ch[2]);
frm.add(txt4);
txt4.setFont(font);
frm.add(txt5);
txt5.setFont(font);
frm.add(txt7);
txt7.setFont(font);
frm.add(txt8);
txt8.setFont(font);
frm.add(txt9);
txt9.setFont(font);
frm.add(txt10);
txt10.setFont(font);
frm.add(txt11);
txt11.setFont(font);
frm.add(txt12);
txt12.setFont(font);
frm.add(txt13);
txt13.setFont(font);
frm.add(txt14);
txt14.setFont(font);
frm.add(txt15);
txt15.setFont(font);
frm.add(txt16);
txt16.setFont(font);
frm.add(txt17);
txt17.setFont(font);
frm.add(txt18);
txt18.setFont(font);
frm.add(txt19);
txt19.setFont(font);
frm.add(txt20);
txt20.setFont(font);
frm.add(txt21);
txt21.setFont(font);
frm.add(txt22);
txt22.setFont(font);
frm.add(txtr);
Font fon=new Font("楷体",Font.BOLD,20);
txtr.setFont(fon);
//以下为txt1事件
txt1.addFocusListener(new FocusAdapter(){
public void focusGained(FocusEvent e){
System.out.println("helloworld");
txt1.setText("");
}
public void focusLost(FocusEvent e){
txt2.setText(txt1.getText());
txt2.setText(ch1[3]);//出错,找不到符号
txt3.setText(ch1[2]);//出错,找不到符号
txt4.setText(ch1[1]);//出错,找不到符号
txt5.setText(ch1[0]); //出错,找不到符号
}
});
txt6.addFocusListener(new FocusAdapter(){
public void focusGained(FocusEvent e){
txt6.setText("");
}
public void focusLost(FocusEvent e){
txt7.setText(ch2[3]);} //出错,找不到符号
});
//文本域换行尝试 成功
txtr.setText("计算过程如下:");
txtr.append("\n");
txtr.append("3㈩32∧12∨45");
System.out.println(txt1.getText());
frm.setResizable(false);
frm.setVisible(true);
}
}