部分代码如下:
import java.awt.event.*;
import javax.swing.*;
public class Police implements KeyListener,FocusListener{
public void keyPressed(KeyEvent e) {
JTextField t =(JTextField)e.getSource();
//是吧KeyEvent对象强制转换为JTextField类型吧,那它本身是又是什么?
// 事件对象都可以任意转换为其它类型的吗?
if(t.getCaretPosition()>6)
t.transferFocus();
}
public void focusGained(FocusEvent e) {
JTextField text = (JTextField)e.getSource();//同上
text.setText(null);
}
public void focusLost(FocusEvent e) {}
public void keyTyped(KeyEvent e) {}
public void keyReleased(KeyEvent e) {}
}