java - 重新初始化组件时，我的事件监听器停止工作

Question

我有一个具有不同屏幕的程序(由 JPanels 表示)。每次打开屏幕时，我都会重建该面板，并将其放置在 JFrame 上。

现在，当我第一次构建面板(始终是相同的功能)并按下按钮时，附加到它的代码将运行。当我重建屏幕时，eventSource 将永远不会等于实际的 eventSource。

查看代码:

public class NewUserScreen extends JPanel implements MouseListener{
    //SButton inherits from Component
    SButton sb;

    ...

    public void SetFields(){
        removeAll();
        revalidate();
        repaint();

        ...     

        sb = new SButton(new Point(282, 295), "Save");
        sb.addMouseListener(this);
        add(sb);

        ...
    }

    ...

    @Override
    public void mouseReleased(MouseEvent arg0) {
        if(arg0.getSource().equals(sb)){
            DBManager.addUser(...);
        }else{
            //So after the 2nd build, it will always run this code :(
            ScreenManager.OpenAdminS();
        }

    }
}

Answer 1

1. have this program with different screens (represented by JPanels). Every time a screen opens I rebuild that panel, and place it on the JFrame.

   • 使用CardLayout而不是删除并添加新 View 到 JFrame

2. Now, when I build the panel for the first time (always the same function) and press a button, the code attached to it will run. When I rebuild the screen the eventSource will never be equal to the actual eventSource.

   • 必须为父级(在您的情况下为JFrame)调用一次(re)validate()和repaint()，如下最后的代码行(在完成对容器的所有更改之后)