Question

java中关于JTextField清空问题

输入框中默认显示提示信息，当点击输入时自动清空，这句代码怎么写，谢谢

Answer 1

这个样子吧
import java.awt.FlowLayout;
import java.awt.event.*;

import javax.swing.*;
public class TestTextField {

/**
* @param args
*/
JFrame jf;
JTextField jt;
final String name="please input your name";
public TestTextField()
{
jt=new JTextField(name);
jt.addFocusListener(new FocusListener(){

@Override
public void focusGained(FocusEvent arg0) {
// TODO Auto-generated method stub
if(jt.getText()==name||name.equals(jt.getText()))
jt.setText("");
}
@Override
public void focusLost(FocusEvent arg0) {
// TODO Auto-generated method stub
if(jt.getText()==""||jt.getText().equals(""))
jt.setText(name);
}});
jf=new JFrame();
jf.setLayout(new FlowLayout());
jf.add(new JTextField(8));
jf.add(jt);
jf.setBounds(200,200,100,100);
jf.setVisible(true);
}
public static void main(String[] args) {
// TODO Auto-generated method stub
new TestTextField();
}

}

Answer 2

触发输入框的MouseClicked事件，里面写 jtextField.setText("");这就就可以了

Answer 3

使用得到焦点和失去焦点的方法