java - 我如何从另一个类设置Visible(true) JLabel

Question

这是我的代码。我在 Check1 标签上遇到问题，因为我希望它在答案正确时可见，顺便说一下，我正在使用卡片布局。我删除了不重要的代码

public class Category1 extends JPanel {
public static JLabel Check1;
  public Category1 () {


    Check1 = new JLabel(newImageIcon(getClass().getResource("Buttons/Check.png")));
    Check1.setBounds(75 , 305, 40, 40);
    Check1.setVisible(false);
    add(Check1);

}}

这是另一个类，如果您单击 Submit1 按钮，并且 JTextField 中的文本正确，我希望 Check1 按钮可见。

public class QuizPanelc1 {
   JPanel Quiz1;
   JTextField Answer1;
   JButton Submit1;

public QuizPanelc1(){

    Answer1 = new JTextField();
    Answer1.setBounds(180, 480, 200, 40);
    Quiz1.add(Answer1);
    Submit1 = new JButton(new ImageIcon(getClass().getResource("Buttons/SubmitButton.png")));
    Submit1.setBounds(390, 480, 40, 40);
    Quiz1.add(Submit1);

ButtonHandler1 events1 = new ButtonHandler1();
    Submit1.addActionListener(events1);
    Back1.addActionListener(events1)

}
private class ButtonHandler1 implements ActionListener {
    public void actionPerformed (ActionEvent eventClick) {
        Object event = eventClick.getSource();
        Category1 c1 = new Category1();

        if(Submit1==event)
        {
            if(Answer1.getText().equalsIgnoreCase("Fila"))
            {
                Answer1.setEditable(false);

                JOptionPane.showMessageDialog(null, "Correct");
                c1.Check1.setVisible(true);

            }
            else
            {

                JOptionPane.showMessageDialog(null, "Wrong Answer");

            }
        }
        else
        {
         System.exit(1);
        }
}}

Answer 1

使 check1 成为类的字段并且不是静态的，然后创建一个用于设置可见性的公共(public)方法:

示例:

public class Category1 extends JPanel {
    private JLabel check1;

    public void setCheck1Visibility(boolean visible) {
        check1.setVisible(visible);
    }

    public Category1() {
        check1 = new JLabel(new ImageIcon(getClass().getResource("Buttons/Check.png")));
        check1.setBounds(75, 305, 40, 40);
        check1.setVisible(false);
        add(check1);
    }
}

<小时/>

既然您有一个 Category1 实例，您可以执行以下操作:

Category1 c1 = new Category1();
c1.setCheck1Visibility(true);
or 
c1.setCheck1Visibility(false);