Java Swing GUI - 在底部添加单个边框

Question

我想在窗口底部添加一个边框，我已经尝试使用MatteBorder但边框仅扩展到由我的 GridBagLayout 组成的面板.(如图所示)。我知道这是因为我已经为该面板设置了边框，但当我将其添加到新的子面板，然后将该面板添加到主面板，最终将主面板添加到 JFrame 时，边框甚至没有出现。 。我希望边框沿着窗口底部延伸。

这是我的代码:

public class Admin_hs extends JFrame {

    JButton bking_btn= new JButton("Bookings");
    JButton fd_btn= new JButton("Financial Data");
    JButton ctm_btn= new JButton("Customers");
    JButton room_btn= new JButton("Rooms");
    JButton adc_btn= new JButton("Additional Costs");
    JButton endb_btn= new JButton("Ending Bookings");

    //Images
    JLabel bking_img= new JLabel();
    JLabel fd_img= new JLabel();
    JLabel ctm_img= new JLabel();
    JLabel room_img= new JLabel();
    JLabel adc_img= new JLabel();
    JLabel endb_img= new JLabel();

    ///Panels

    JPanel pnl1= new JPanel();
    JPanel pnl= new JPanel();

    ///Constructors

    public Admin_hs(){
        this.setTitle("Welcome Admin!");
        this.setLayout(new GridBagLayout());

        ///Setting a layout


        GridBagConstraints gbc = new GridBagConstraints();
        gbc.gridwidth= GridBagConstraints.REMAINDER;
        gbc.fill= gbc.HORIZONTAL;

        pnl.setLayout(new GridBagLayout());

        GridBagConstraints gc= new GridBagConstraints();

        ///First Column of Grid


        gc.insets = new Insets(6, 6, 6, 6);
        gc.anchor = GridBagConstraints.WEST;
        gc.weightx = 0.5;
        gc.weighty = 0.5;

        gc.gridx = 0;
        gc.gridy = 0;

        pnl.add(bking_btn, gc);

        gc.gridx = 0;
        gc.gridy = 1;
        pnl.add(fd_btn, gc);

        gc.gridx = 0;
        gc.gridy = 2;
        pnl.add(ctm_btn, gc);

        gc.gridx = 0;
        gc.gridy = 3;
        pnl.add(room_btn, gc);

        gc.gridx = 0;
        gc.gridy = 4;
        pnl.add(adc_btn, gc);

        gc.gridx = 0;
        gc.gridy = 5;
        pnl.add(endb_btn, gc);


        /////second column of grid



        gc.anchor = GridBagConstraints.WEST;
        gc.gridx = 1;
        gc.gridy = 0;
        bking_img.setIcon(new ImageIcon("C:/Users/Diksha/Desktop/OOSD Assignment/icons/60-60/booking.jpg"));
        pnl.add(bking_img, gc);

        gc.gridx = 1;
        gc.gridy = 1;
        fd_img.setIcon(new ImageIcon("C:/Users/Diksha/Desktop/OOSD Assignment/icons/60-60/fd.jpg"));
        pnl.add(fd_img, gc);

        gc.gridx = 1;
        gc.gridy = 2;
        ctm_img.setIcon(new ImageIcon("C:/Users/Diksha/Desktop/OOSD Assignment/icons/60-60/guest.jpg"));
        pnl.add(ctm_img, gc);

        gc.gridx = 1;
        gc.gridy = 3;
        room_img.setIcon(new ImageIcon("C:/Users/Diksha/Desktop/OOSD Assignment/icons/60-60/room.jpg"));
        pnl.add(room_img, gc);

        gc.gridx = 1;
        gc.gridy = 4;
        adc_img.setIcon(new ImageIcon("C:/Users/Diksha/Desktop/OOSD Assignment/icons/60-60/adc.jpg"));
        pnl.add(adc_img, gc);

        gc.gridx = 1;
        gc.gridy = 5;
        endb_img.setIcon(new ImageIcon("C:/Users/Diksha/Desktop/OOSD Assignment/icons/60-60/endb.png"));
        pnl.add(endb_img, gc);

        pnl.setBorder(BorderFactory.createMatteBorder(0, 0, 2, 0, Color.BLACK));

        this.add(pnl);



    }

}

主要

public class Admin_main {

 public static void main(String[] args) {

    Admin_hs adm= new Admin_hs();

    adm.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    adm.pack();
    adm.setVisible(true);
    adm.setSize(780,520);

    }

}

目前它看起来像这样:

我希望窗口看起来像这样(这是使用 Windows Paint 完成的):

Answer 1

您在 JPanel pnl 的底部绘制一个 MatteBorder，它的长度不及窗口宽度，因为您的 JPanel pnl不像您在这里看到的窗口宽度那么长。



所以您已经定义了另一个 JPanel pnl1 但您没有使用它。

public Admin_hs(){
    this.setTitle("Welcome Admin!");
    this.setLayout(new GridBagLayout());

        ///Setting a layout
    pnl1.setLayout(new GridBagLayout());   // ADD THIS LINE
    GridBagConstraints gbc = new GridBagConstraints();
    gbc.gridwidth= GridBagConstraints.REMAINDER;
    gbc.fill= GridBagConstraints.HORIZONTAL;
    gbc.weightx = 1;                       // ADD THIS LINE so it uses all the existing window size in x direction
    pnl1.add(pnl);                         // ADD THIS LINE
    [...]
    // CHANGE THIS LINE to use the bottom border of your pnl1
    pnl1.setBorder(BorderFactory.createMatteBorder(0, 0, 2, 0, Color.BLACK));
    this.add(pnl1,gbc);                    // CHANGE THIS LINE to add pnl1 and not pnl to your main window
}

你会得到这个