java - 框架和 Canvas 变得比指定的大

Question

我不知道为什么我会得到一个超大的窗口，这让我跑圈以适应游戏窗口中的 Sprite 。构造函数应该使所有子组件都能相互适应，但 Canvas 或框架中似乎有一些额外的填充。我很难弄清楚罪魁祸首是什么。我的框架的大小不应大于 800x600(不包括操作系统装饰，谈论的是容器)。

Panel: java.awt.Rectangle[x=0,y=0,width=810,height=610]
Frame: java.awt.Rectangle[x=0,y=0,width=816,height=638]
Canvas:java.awt.Rectangle[x=0,y=0,width=816,height=638]

如您所见，边界比我指定的要大。

类(class):

public class GameFrame {
private JFrame frame;
private JPanel panel;
private Canvas canvas;
private BufferStrategy bufferStrategy;
private Graphics2D g;
private int width;
private int height;

public GameFrame(Color bgColor) {
    this.width = GameEngine.GAMEDIMENSION[0]; // 800
    this.height = GameEngine.GAMEDIMENSION[1]; // 600
    this.frame = new JFrame();
    this.panel = (JPanel) frame.getContentPane();
    this.panel.setPreferredSize(new Dimension(width, height));
    this.panel.setLayout(null);
    this.panel.setBackground(bgColor);
    this.canvas = new Canvas();
    this.canvas.setBounds(0, 0, width, height);
    this.canvas.setIgnoreRepaint(true);
    this.frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

    this.frame.pack();
    this.frame.setResizable(false);
    this.frame.setVisible(true);
    this.panel.add(canvas);
    this.canvas.createBufferStrategy(2);
    this.bufferStrategy = canvas.getBufferStrategy();
    this.g = (Graphics2D) bufferStrategy.getDrawGraphics();
    this.canvas.requestFocus();

}

主要:

public static void main(String[] args) {
    GameFrame gf = new GameFrame(Color.black);
    System.out.println("Panel: " + gf.panel.getBounds());
    System.out.println("Frame: " + gf.frame.getBounds());
    System.out.println("Canvas:" + gf.frame.getBounds());

    for (int R = 0; R < 255; R++) {
        for (int B = 0; B < 255; B++) {
            for (int G = 0; G < 255; G++) {
                gf.g.setColor(Color.black);
                gf.g.fillRect(0, 0, gf.width, gf.height);
                gf.g.setColor(new Color(R, B, G));
                gf.g.fillRect(0, 0, gf.width, gf.height);
                gf.bufferStrategy.show();
            }
        }
    }

}

主要是我尝试循环方 block 只是为了看看效果。

Answer 1

交换 pack 和 setResizes 调用，以便 pack 是第二个调用。

在下面的示例中，它将在面板上写入 200x200，如果交换调用，它将写入 210x210

这是一个已知的“问题”

import java.awt.BorderLayout;
import java.awt.Dimension;
import java.awt.EventQueue;
import java.awt.FontMetrics;
import java.awt.Graphics;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.UIManager;
import javax.swing.UnsupportedLookAndFeelException;

public class TestResizeFrame {

    public static void main(String[] args) {
        new TestResizeFrame();
    }

    public TestResizeFrame() {
        EventQueue.invokeLater(new Runnable() {
            @Override
            public void run() {
                try {
                    UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
                } catch (ClassNotFoundException | InstantiationException | IllegalAccessException | UnsupportedLookAndFeelException ex) {
                }

                JFrame frame = new JFrame("Testing");
                frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
                frame.setLayout(new BorderLayout());
                frame.add(new TestPane());
                // Will appear as 200x200, swap them and it will appear as 210x210
                frame.setResizable(false);
                frame.pack();
                frame.setLocationRelativeTo(null);
                frame.setVisible(true);
            }
        });
    }

    public class TestPane extends JPanel {

        @Override
        public Dimension getPreferredSize() {
            return new Dimension(200, 200);
        }

        @Override
        protected void paintComponent(Graphics g) {
            super.paintComponent(g); 
            FontMetrics fm = g.getFontMetrics();
            g.drawString(getWidth() + "x" + getHeight(), 0, fm.getAscent());
        }

    }

}