小编Rex*_*ozo的帖子

所以这就是概念:简单地说,有一个带有"名称"作为值的文本框,我希望如果我单击文本框中的任何位置,"名称"值将消失.这就是我在我的代码中所做的:

JTextField t1 = new JTextField("Name", 10);

t1.addActionListener(new ActionListener(){
            public void actionPerformed(ActionEvent cl){
                t1.setText(" ");
            }
        });

没有语法错误,但是当我运行程序并单击文本框中的某个位置时,没有任何反应,值"名称"仍然存在

非常感谢任何帮助,谢谢!

bSub.addActionListener(new ActionListener(){
           public void actionPerformed(ActionEvent e){
               if(t1.getText().equals("Name") || t2.getText().equals("Section") || t3.getText().equals("Age")){
                   JOptionPane.showMessageDialog(null, "Please fill in the incomplete fields");
                }
                //If the 'if statement' above is true, these code below will not execute
               t8.setText(t1.getText() + " of " + t2.getText() + " -- " + t3.getText() + " years old");
               t9.setText(t1.getText() + " of " + t2.getText() + " -- " + t3.getText() + " years old");
               t10.setText(t1.getText() + " of " + t2.getText() + " -- " + t3.getText() + …