Question

我收到错误“ java.lang.IllegalArgumentException：将容器的父级添加到自身”。在我的代码中，我显然看不到我在做什么。我看了另一个来自同一错误的人的stack.overflow线程，他们显然做得不好。在他们的案例中，有人回答说，是由于将一个容器添加到另一个容器，然后将其中一个容器添加到另一个容器（link)而引起的某种无限循环。我不确定为什么我的任何容器添加都会如果这是问题所在，则会导致无限循环。提供的解决方案是说使用JPanels。我已经尝试了所有“ this.getContentPane（）”，所有JPanels和一个“ this.getContentPane（）”的代码和其他Jpanels，但总是会收到相同的错误。我很好奇：

为什么会出现错误？
好像我正确地实现了CardLayout吗？
使用JPanel和“ this.getContentPane（）”之间的功能区别是什么。

我希望再减少一些代码，如果需要的话，我会很乐意这样做。但是我拿出了我非常有信心不会影响代码的所有内容（其他按钮，标签，文本字段），但是我认为可能是所有问题，或者如果删除了某些内容可能会无意间破坏代码。

package comp1206.sushi.server;
import java.awt.CardLayout;
import java.awt.Component;
import java.awt.Container;
import javax.swing.JComponent;
import javax.swing.JPanel;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.text.JTextComponent;
import javax.swing.JTextField;
import javax.swing.SwingUtilities;
import java.awt.GridBagLayout;
import java.util.concurrent.Executors;
import java.awt.CardLayout;
import java.awt.GridBagConstraints;
import javax.swing.JLabel;
import java.util.concurrent.ScheduledExecutorService;
import java.util.concurrent.TimeUnit;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import comp1206.sushi.common.*;
import comp1206.sushi.server.ServerInterface.UnableToDeleteException;
import java.awt.Dimension;

/**
 * Provides the Sushi Server user interface
 *
 */
public class ServerWindowTest extends JFrame implements UpdateListener {

    private static final long serialVersionUID = -4661566573959270000L;
    private ServerInterface server;



    /**
     * Create a new server window
     * @param server instance of server to interact with
     */
    public ServerWindowTest(ServerInterface server) {
        super("Restaurant Server");
        this.server = server;
        this.setTitle(server.getRestaurantName() + " Server");
        server.addUpdateListener(this);

        Container panel = this.getContentPane();
        Container entryFields = new JPanel();
        Container ordersPanel = new JPanel();
        Container dishesPanel = new JPanel();

        JButton ordersButton = new JButton("Orders");
        JButton dishesButton = new JButton("Dishes");

        CardLayout c1 = new CardLayout();

        panel.setLayout(new GridBagLayout());

        entryFields.setLayout(c1);
        ordersPanel.setLayout(new GridBagLayout());
        dishesPanel.setLayout(new GridBagLayout());

        GridBagConstraints ordersPanelConstraints = new GridBagConstraints();
        GridBagConstraints dishesPanelConstraints = new GridBagConstraints();

        GridBagConstraints buttonConstraints = new GridBagConstraints();
        GridBagConstraints viewScreenConstraints = new GridBagConstraints();

        GridBagConstraints label1Constraints = new GridBagConstraints();
        GridBagConstraints textField1Constraints = new GridBagConstraints();        

        buttonConstraints.gridwidth = 1;
        buttonConstraints.gridy = 0;
        viewScreenConstraints.gridwidth = 9;
        viewScreenConstraints.gridheight = 6;
        viewScreenConstraints.gridy = 1;
        label1Constraints.gridy = 0;
        label1Constraints.gridx = 0;

        textField1Constraints.gridy = 0;
        textField1Constraints.gridx = 0;

        entryFields.add(ordersPanel, "ordersPanel");
        entryFields.add(dishesPanel, "dishesPanel");

        c1.show(entryFields, "ordersPanel");

        JTextField viewScreen = new JTextField();   

        viewScreen.setPreferredSize(new Dimension(600, 200));

        JLabel orders1Label = new JLabel("order 1");
        JLabel dishes1Label = new JLabel("dish 1");     

        JTextField orders1TextField = new JTextField();
        JTextField dishes1TextField = new JTextField(); 

        ordersPanel.add(orders1Label, label1Constraints);
        ordersPanel.add(orders1TextField, textField1Constraints);
        dishesPanel.add(dishes1Label, label1Constraints);
        dishesPanel.add(dishes1TextField, textField1Constraints);

        panel.add(ordersButton, buttonConstraints);     
        panel.add(dishesButton, buttonConstraints); 

        panel.add(viewScreen, viewScreenConstraints);

        panel.add(entryFields);

        ordersButton.addActionListener(new ActionListener(){
            public void actionPerformed(ActionEvent arg0) {
                c1.show(entryFields, "ordersPanel");
            }
        });

        dishesButton.addActionListener(new ActionListener(){
            public void actionPerformed(ActionEvent arg0) {
                c1.show(entryFields, "dishesPanel");
            }
        });

        //Display window
        setSize(800,600);
        setLocationRelativeTo(null);
        setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        setVisible(true);

        //Start timed updates
        startTimer();
    }


    /**
     * Start the timer which updates the user interface based on the given interval to update all panels
     */
    public void startTimer() {
        ScheduledExecutorService scheduler = Executors.newScheduledThreadPool(1);     
        int timeInterval = 5;

        scheduler.scheduleAtFixedRate(() -> refreshAll(), 0, timeInterval, TimeUnit.SECONDS);
    }

    /**
     * Refresh all parts of the server application based on receiving new data, calling the server afresh
     */
    public void refreshAll() {

    }

    @Override
    /**
     * Respond to the model being updated by refreshing all data displays
     */
    public void updated(UpdateEvent updateEvent) {
        refreshAll();
    }

}

java.lang.IllegalArgumentException：向其自身添加容器的父项（同名线程中的解决方案不起作用）

0 个答案: