java - GridBagLayout 添加后不要使组件 "jump"

Question

我想将 GridBagLayout 用于具有 <= 3 列和可变行数的布局(如果有人知道可以轻松做到这一点的另一种布局，请告诉我)，每次我按下“添加”按钮square 将被添加到第一个可用的位置。像这样:

|x x x|
|x x x|
|x o  |

x 是正方形，当我按下添加时，应该在 o 现在所在的位置添加一个新正方形。 我设法像这样“让它工作”:

public void addSquare(Square square) {
    c.fill = GridBagConstraints.NONE;
    c.gridx = nrOfSquares % 3;
    c.gridy = (int) (nrOfSquares / 3);
    c.weighty = 1;
    c.weightx = 1;
    c.anchor = GridBagConstraints.NORTHWEST;
    c.insets = new Insets(5, 5, 5, 5);
    this.container.add(square, c);
    this.container.revalidate();
    ++nrOfSquares;
}

问题是我添加的第二个方 block 是这样添加的:

|x  x  |

请注意，第一个方格和第二个方格之间有一个额外的空间。添加额外的行时，我遇到了同样的问题。

现在我该如何修改我的代码，使方 block 不会像我给出的第一个示例那样“跳跃”和添加？

编辑:根据要求，我将其转换为常规 GridLayout 后的一个更好的示例:

public class Square extends JPanel {
   public Square() {
       super();     
       Dimension SIZE = new Dimension(200, 200);
       this.setSize(SIZE);
       this.setPreferredSize(SIZE);
       this.setMinimumSize(SIZE);
       this.setMaximumSize(SIZE);

       this.setBackground(Color.ORANGE);

       this.setVisible(true);
   }
}

public class SquareContainer extends JPanel {
    protected JPanel realContainer;

    public SquareContainer(int width, int height) {
        super();
        this.setLayout(new BorderLayout());
        this.setBackground(Color.WHITE);
        this.setSize(width, height);
        this.realContainer = new JPanel();
        GridLayout layout = new GridLayout(0, 3);
        layout.setHgap(10);
        layout.setVgap(10);
        this.realContainer.setLayout(layout);
        this.realContainer.setBackground(this.getBackground());
        JScrollPane scroller = new JScrollPane(this.realContainer);
        scroller.getVerticalScrollBar().setUnitIncrement(20);
        this.add(scroller, BorderLayout.CENTER);
    }

    public void addSquare(Square square) {
        this.realContainer.add(square);
        this.realContainer.revalidate();
    }
}

我只是将其添加到 JFrame 中:

public class TheGreatFrame extends JFrame {
    public TheGreatFrame() {
        super();
        this.setSize(800, 800);
        this.setLocationRelativeTo(null);
        this.setLayout(new BorderLayout());
        this.setResizable(false);

        this.add(new SquareContainer(750, 660), BorderLayout.CENTER);

        this.setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);
        this.setVisible(true);
    }
}

Answer 1

一个使用GridLayout的小例子程序:

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

public class GridLayoutEg {

   private static void createAndShowGui() {
      final JPanel centerPanel = new JPanel(new GridLayout(0, 3)); 

      JButton addBtn = new JButton(new AbstractAction("Add Button") {

         @Override
         public void actionPerformed(ActionEvent e) {
            centerPanel.add(new JButton("X"));
            centerPanel.revalidate();
            centerPanel.repaint();  

            SwingUtilities.getWindowAncestor(centerPanel).pack();
         }
      });
      JPanel btnPanel = new JPanel();
      btnPanel.add(addBtn);

      JPanel mainPanel = new JPanel(new BorderLayout());
      mainPanel.add(centerPanel, BorderLayout.CENTER);
      mainPanel.add(btnPanel, BorderLayout.PAGE_END);
      JFrame frame = new JFrame("GridLayoutEg");
      frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
      frame.getContentPane().add(mainPanel);
      frame.pack();
      frame.setLocationRelativeTo(null);
      frame.setVisible(true);
   }

   public static void main(String[] args) {
      SwingUtilities.invokeLater(new Runnable() {
         public void run() {
            createAndShowGui();
         }
      });
   }
}