在没有布局的面板/框架中添加弹出式菜单

Question

我需要创建一个GUI，必须提供一个弹出菜单。我设法做到这一点，但它只出现，如果我设置布局null -在这种情况下，有问题，我的功能都不出现，只有弹出式菜单。我不允许使用Java。秋千或者别的什么

我如何管理让弹出菜单出现没有设置我的布局null?

我希望你能理解我的问题，在这里你可以检查我的代码:

public class ServerStart {
    public static void main(String[] args) {
        ServerInterface serverInterface = new ServerInterface();
        serverInterface.setVisible(true);
    }
}
class ServerInterface extends Frame implements Runnable {
    private int portNr;
    private MenuBar menuBar;
    private String fileName;
    private TextField portText;
    private PopupMenu popupMenu;
    private Thread interfaceThread;
    private ServerThread serverThread;
    private Panel mainPanel, displayPanel;
    private Menu menuServer, menuFile, menuDatabase, menuProgram;
    private MenuItem start, stop, create, choose, connect, beenden, popupstart,
            popupstop, popupclose;
    private Label title, port, textClient, textStatus, clientNr, serverStatus;
    public static int client = 0;
    ServerSocket serverSocket;
    ServerInterface serverInterface;
    public ServerInterface() {
        super("ADRELI 4 GUI - SERVER");
        this.setBounds(325, 50, 475, 355);
       // this.setLayout(null);
        this.setLayout(new BorderLayout());
        this.setResizable(false);
        this.enableEvents(AWTEvent.MOUSE_EVENT_MASK);
        this.addWindowListener(new WindowAdapter() {
            @Override
            public void windowClosing(WindowEvent we) {
                DialogWindow dialogWindow = new DialogWindow(
                        new ServerInterface(), "Programm beenden",
                        "Wollen Sie das Programm wirklich beenden?",
                        "OK", "Abbrechen");
                if (dialogWindow.getAnswer()) {
                    System.exit(0);
                }
            }
        }
        );
        mainPanel = new Panel();
        mainPanel.setBackground(Color.darkGray);
        mainPanel.setLayout(null);
        this.add(mainPanel);
        title = new Label("SERVER");
        title.setBackground(Color.white);
        title.setBounds(20, 20, 425, 100);
        title.setAlignment(Label.CENTER);
        title.setFont(new Font("Arial", Font.BOLD, 25));
        mainPanel.add(title);
        menuBar = new MenuBar();
        menuServer = new Menu("Server...");
        start = new MenuItem("Start");
        stop = new MenuItem("Stop");
        stop.setEnabled(false);
        menuBar.add(menuServer);
        menuServer.add(start);
        menuServer.add(stop);
        this.setMenuBar(menuBar);
        menuFile = new Menu("Datei...");
        create = new MenuItem("Anlegen");
        choose = new MenuItem("Auswaehlen");
        menuFile.add(create);
        menuFile.add(choose);
        menuBar.add(menuFile);
        menuDatabase = new Menu("Datenbank...");
        connect = new MenuItem("Verbinden");
        menuDatabase.add(connect);
        menuBar.add(menuDatabase);
        menuProgram = new Menu("Programm...");
        beenden = new MenuItem("Beenden");
        menuProgram.add(beenden);
        menuBar.add(menuProgram);
        popupMenu = new PopupMenu();
        popupstart = new MenuItem("Start");
        popupstop = new MenuItem("Stop");
        popupstop.setEnabled(false);
        popupclose = new MenuItem("Beenden");
        popupMenu.add(popupstart);
        popupMenu.add(popupstop);
        popupMenu.addSeparator();
        popupMenu.add(popupclose);
        this.add(popupMenu);
        displayPanel = new Panel();
        displayPanel.setBounds(20, 140, 425, 150);
        displayPanel.setLayout(null);
        displayPanel.setBackground(Color.lightGray);
        textStatus = new Label("Serverstatus:");
        textStatus.setBounds(20, 20, 300, 30);
        textStatus.setBackground(Color.white);
        textStatus.setFont(new Font("Arial", Font.BOLD, 15));
        displayPanel.add(textStatus);
        textClient = new Label("Aktive Clients:");
        textClient.setBounds(20, 60, 300, 30);
        textClient.setBackground(Color.white);
        textClient.setFont(new Font("Arial", Font.BOLD, 15));
        displayPanel.add(textClient);
        port = new Label("Portnummer:");
        port.setBounds(20, 100, 300, 30);
        port.setBackground(Color.white);
        port.setFont(new Font("Arial", Font.BOLD, 15));
        displayPanel.add(port);
        serverStatus = new Label();
        serverStatus.setBackground(Color.red);
        serverStatus.setBounds(355, 20, 50, 30);
        displayPanel.add(serverStatus);
        clientNr = new Label(" 0 ");
        clientNr.setBackground(Color.white);
        clientNr.setBounds(355, 60, 50, 30);
        clientNr.setAlignment(Label.CENTER);
        clientNr.setFont(new Font("Arial", Font.BOLD, 15));
        displayPanel.add(clientNr);
        portText = new TextField("56789");
        portText.setBackground(Color.white);
        portText.setBounds(355, 100, 50, 30);
        portText.setFont(new Font("Arial", Font.BOLD, 15));
        displayPanel.add(portText);
        start.addActionListener(new ItemClicked());
        stop.addActionListener(new ItemClicked());
        choose.addActionListener(new ItemClicked());
        create.addActionListener(new ItemClicked());
        connect.addActionListener(new ItemClicked());
        beenden.addActionListener(new ItemClicked());
        popupstart.addActionListener(new ItemClicked());
        popupstop.addActionListener(new ItemClicked());
        popupclose.addActionListener(new ItemClicked());
        mainPanel.add(displayPanel);
    }
    @Override
    public void processMouseEvent(MouseEvent me) {
        if (me.isPopupTrigger()) {
            popupMenu.show(me.getComponent(), me.getX(), me.getY());
        }
        super.processMouseEvent(me);
    }

Answer 1

删除this.add(popupMenu);，它应该与非空布局工作良好。弹出式菜单被设计为在其他组件上显示，所以在这种情况下，您不需要将它添加到其他组件上。