我有两份档案， Display.java （先）然后 Lancher.java （第二）。他们都在同一个项目下，但是两个不同的类。我想有一个显示图像，但宽度和高度从发射器文件上来了错误。我不知道为什么，因为宽度和高度都不一样 public 在 Display 文件。

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

public class Display extends JFrame {

    private Canvas canvas;

    public Display(int width, int height) {
        setTitle("Game");
        setDefaultCloseOperation(EXIT_ON_CLOSE);
        //Process will still be running but application closes when cross is pressed
        setResizable(false);

        canvas = new Canvas();
        canvas.setPreferredSize(new Dimension(width, height));
        //Set size to pass in with dimension
        canvas.setFocusable((false));
        add(canvas);
        pack();
        //Add canvas to display & calculate size of display frame

        setLocationRelativeTo (null);
        //To open frame in the center of screen as opposed to side
        setVisible(true);

    }

}

启动器.java

public class Launcher {

    public static void main(String[] args) {
        Display display = new Display( width: 800, height: 600);
    }

}