java文本框失去焦点事件_如何监听JTextField的失去焦点事件

展开全部

让JTextField文本框响应焦62616964757a686964616fe58685e5aeb931333363386662点事件 即可.

核心代码JTextFieldjtf=newJTextField(10);

jtf.addFocusListener(newFocusListener(){

publicvoidfocusLost(FocusEvente){//失去焦点时

System.out.println("失去了焦点");

jtf.setBackground(Color.WHITE);

}

publicvoidfocusGained(FocusEvente){//获得焦点时

System.out.println("获得了焦点");

tf.setBackground(Color.PINK);

}

});

效果图

参考代码importjava.awt.*;

importjava.awt.event.*;

importjavax.swing.*;

publicclassTextFrameextendsJFrame{

JTextFieldjtf;

publicTextFrame(){

JPaneljp=newJPanel();

jtf=newJTextField(10);

jtf.addFocusListener(newFocusListener(){

@Override

publicvoidfocusLost(FocusEvente){//失去焦点时

System.out.println("失去了焦点");

jtf.setBackground(Color.WHITE);

}

@Override

publicvoidfocusGained(FocusEvente){//获得焦点时

System.out.println("获得了焦点");

jtf.setBackground(Color.PINK);

}

});

jp.add(jtf);

JButtonjb=newJButton("点击按钮,文本框会失去焦点");

add(jb,BorderLayout.NORTH);

add(jp,BorderLayout.SOUTH);

setTitle("DEMO");

setSize(300,220);//窗口大小

setLocationRelativeTo(null);//窗口居中

setDefaultCloseOperation(EXIT_ON_CLOSE);//窗口点击关闭时,退出程序

setVisible(true);

}

publicstaticvoidmain(String[]args){

newTextFrame();

}

}