Question

我有三个课程：一个是主要课程：

public class Thera {
    public static void main(String[] args) {
        TheraGUI start = new TheraGUI();
    }

}

一个是GUI

public class TheraGUI extends JFrame {
    public TheraGUI(){
        Board board = new Board();
        this.setLayout(new GridBagLayout());
        this.setTitle("Thera");
        this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        this.setVisible(true);
        this.add(board);
        this.pack();
    }
}

最后是我的董事会：

package thera;
import java.awt.*;
import java.awt.event.*;
import java.util.*;
import javax.swing.*;

public class Board extends JPanel {
  JLayeredPane layeredpane;
  JPanel board;
  JLabel piece;
  int xAdj;
  int yAdj;
  private static final String imageFolderPath = "src/resources/images/";
  Dimension dimension = new Dimension(500, 500);

  public Board(){
      //create the layered pane  
      layeredpane = new JLayeredPane();
      layeredpane.setPreferredSize(dimension);
      this.add(layeredpane);

  //create the Board
  board = new JPanel();
  board.setLayout(new GridLayout(7,9));
  board.setPreferredSize(dimension);

  layeredpane.add(board, JLayeredPane.DEFAULT_LAYER);

  for(int c = 0; c < 7; c++){
      for(int r = 0; r < 9; r++){
          JPanel square = new JPanel(); 
          square.setLayout(new BorderLayout());
          square.setBackground(new Color(255, 204, 051));
          board.add(square);
      }
  }

 } 

}

我的问题：我的主板不会出现！附加信息：主要布局是gridbaglayout，在单元格中我添加了一个JPanel，在JPANel中我添加了一个分层窗格。

Answer 1

您在设置可见性后添加了一个组件（从而更改了层次结构）。对于事情的运作方式，Swing有点迂腐。

public class TheraGUI extends JFrame {
    public TheraGUI(){
        Board board = new Board();
        this.setLayout(new GridBagLayout());
        this.setTitle("Thera");
        this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        // note the order
        this.add(board);
        this.pack();
        this.setVisible(true);
    }
}

Answer 2

分层窗格使用空布局，这意味着您负责设置添加到分层面板的组件的大小/位置：

board.setPreferredSize(dimension);
board.setSize(dimension); // added

请注意，您不应该使用硬编码首选大小。您应该创建一个表示方块的类，然后覆盖该类的getPreferredSize()方法。

董事会的广场不会出现。

2 个答案: