java - JTabbedPane 与 GridBagLayout

Question

我理解了 JTabbedPane 和 GridBagLayout 背后的概念。然而，当我尝试同时使用两者时，我失败了。也就是说，当我使用 GBLayout 时，我的其他选项卡(每个选项卡具有不同的功能)不会显示。请帮忙。谢谢。

这是我的代码:

    import java.awt.*;
    import javax.swing.*;

    public class Tryout extends JFrame {

    private static final long serialVersionUID = 1L;
    private     JTabbedPane tabbedPane;
    private     JPanel      panel1;
    private     JPanel      breakfast;

    public Tryout()
    {   
        JPanel topPanel = new JPanel();
        topPanel.setLayout( new BorderLayout() );
        getContentPane().add( topPanel );

        createPage1(); //Tab1
        createPage2(); //Tab2

        tabbedPane = new JTabbedPane();
        tabbedPane.addTab( "Input Form", panel1 );
        tabbedPane.addTab( "Breakfast", breakfast );
        topPanel.add( tabbedPane, BorderLayout.CENTER );
    }

    public void createPage1()
    {
        /* Works fine when I un-comment this
        panel1 = new JPanel();
        panel1.setLayout(new BorderLayout());
        panel1.add(new JLabel("Hi"), BorderLayout.NORTH); 
        */
        //Tabs not getting displayed if I add the code below with GBLayout
        JPanel panel = new JPanel(new GridBagLayout());
        this.getContentPane().add(panel);

        JLabel label = new JLabel("Form");

        JPanel tableButtonPanel = new JPanel();
        tableButtonPanel.add(new JButton("Add Thing"));
        tableButtonPanel.add(new JRadioButton("Delete Thing"));
        tableButtonPanel.add(new JButton("Modify Thing"));

        GridBagConstraints gbc = new GridBagConstraints();

        gbc.gridx = 0;
        gbc.gridy = 0;
        panel.add(label, gbc);

        gbc.gridx = 0;
        gbc.gridy = 2;
        panel.add(tableButtonPanel, gbc);

    }

    public void createPage2()
    {
        breakfast = new JPanel();
        breakfast.setLayout( new BorderLayout() );
        breakfast.add( new JButton( "North" ), BorderLayout.NORTH );
        breakfast.add( new JButton( "South" ), BorderLayout.SOUTH );
        breakfast.add( new JButton( "East" ), BorderLayout.EAST );
        breakfast.add( new JButton( "West" ), BorderLayout.WEST );
        breakfast.add( new JButton( "Center" ), BorderLayout.CENTER );
    }

public static void main(String args[]) {

        Tryout ex = new Tryout();
        ex.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        ex.setSize(750,750);
        ex.setVisible(true);
        ex.setTitle( "Recipe Tracker" );
        ex.setBackground( Color.gray );

    }
}

Answer 1

问题是，在 createPage1 中，您要向 JFrame 添加一个新的 JPanel:

this.getContentPane().add(panel);

它取代了 JFrame 的 BorderLayout.CENTER 中的 topPanel(其中包含 JTabbedPane)位置。因此不会出现 JTabbedPane。

您可以简单地返回已创建的新JPanel并将其添加到您的JTabbedPane:

public JPanel createPage1() {

   JPanel panel = new JPanel(new GridBagLayout());
   // this.getContentPane().add(panel); don't do this...
   ...

   return panel;
}

并添加:

tabbedPane.addTab("Input Form", createPage1());