Question

java问题，JTextField，在输入的过程中（没有打回车），要求在另一个JLabel上同步出现输入的文字。

最近同时做好多项目，时间太紧，求各位帮帮忙吧~

Answer 1

Document dt = textField.getDocument();
dt.addDocumentListener(new Swing_OnValueChanged());

class Swing_OnValueChanged implements DocumentListener { // 输出变化及结果
public void changedUpdate(DocumentEvent e) {
System.out.println("Attribute Changed" + textField.getText());
label.setText(textField.getText());
}

public void insertUpdate(DocumentEvent e) { // 输出变化及结果
System.out.println("Text Inserted:" + textField.getText());
}

public void removeUpdate(DocumentEvent e) { // 输出变化及结果
System.out.println("Text Removed:" + textField.getText());
}
}

Answer 2

import java.awt.FlowLayout;
import java.awt.GridLayout;
import java.awt.event.KeyEvent;
import java.awt.event.KeyListener;

import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JTextField;

public class Update extends JFrame implements KeyListener{

JTextField text = null;
JLabel label = null;

public Update(){
this.setLayout(new FlowLayout());
text = new JTextField(15);
text.addKeyListener(this);
label = new JLabel("实时更新内容的JLabel！");
this.add(text);
this.add(label);
this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
this.setSize(200,100);
this.setLocationRelativeTo(null);
this.setVisible(true);
}

public static void main(String[] args) {
new Update();
}

@Override
public void keyPressed(KeyEvent e) {
// TODO Auto-generated method stub

}

@Override
public void keyReleased(KeyEvent e) {
// TODO Auto-generated method stub
label.setText(text.getText());
}

@Override
public void keyTyped(KeyEvent e) {
// TODO Auto-generated method stub

}

}