Question

我想将GridBagLayout用于具有＆lt; = 3列和可变行数的布局（如果有人知道另一个可以轻松完成此操作的布局，请告诉我），每次按“添加”按钮将在可用的第一个位置添加一个正方形。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现在添加一个新的正方形。我设法“有点让它成功”：

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块是这样添加的：

|x  x  |

请注意，第一个广场和第二个广场之间有一个额外的空间。添加额外行时我遇到同样的问题。

现在我如何修复我的代码，以便方块不会“跳”并像我给出的第一个例子一样添加？

编辑：根据要求，将其转换为常规GridLayout之后的更好示例：

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：

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

使用GridLayout的一个小示例程序：

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();
         }
      });
   }
}

Answer 2

如果所有JComponents可以使用相同的HEIGHT和WEIGHT，那么请查找GridLayout

如果JComponent无法与WEIGHT相同，则将每个"line"放入单独的JPanel（使用BorderLayout或{{1} }}并使用BoxLayout将这些GridLayout放入JPanels

GridBagLayout添加后不要使组件“跳转”

2 个答案: