java - 实际和形式论证

Question

所以，我正在遵循教程并且完全遵循它，但是当我测试时，它会抛出

Exception in thread "main" java.lang.RuntimeException: Uncompilable source code -   constructor Main in class spritesheet.Main cannot be applied to given types;
  required: java.awt.Color
  found: no arguments
  reason: actual and formal argument lists differ in length
at spritesheet.Main.main(Main.java:48)
Java Result: 1

错误!

这是我的代码:

package spritesheet;

import java.awt.Color;
import java.awt.Graphics;
import java.awt.image.BufferedImage;
import java.io.IOException;
import java.util.logging.Level;
import java.util.logging.Logger;
import javax.swing.JFrame;

public class Main extends JFrame {

BufferedImage sprite;
  private final Color Color;

public Main(Color white){
    setSize(800, 600);
    setVisible(true);
    setResizable(true);
    setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    setLocationRelativeTo(null);
    setBackground(Color=white); 
    init();
}


private void init(){
    BufferedImageLoader loader = new BufferedImageLoader();
    BufferedImage spriteSheet = null;
    try {
        spriteSheet = loader.loadImage("spritesheet.png");
    } catch (IOException ex) {
        Logger.getLogger(Main.class.getName()).log(Level.SEVERE, null, ex);
    }
    SpriteSheet ss = new SpriteSheet(spriteSheet);

    sprite = ss.grabSprite(0, 0, 16, 16);
}

@Override
public void paint(Graphics g){
    g.drawImage(sprite, 100, 100, null);
    repaint();

}

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

此代码旨在在白色背景上显示静态图像，但它要么引发错误，要么显示透明背景。然后它就会出现并让我烦恼。 :(我做错了什么？？？

Answer 1

你这样称呼你的类(class)

Main Main = new Main();

但是您需要向其传递一个参数，因为您将其定义为

public Main(Color white) { ... }

你可以将其更改为

Main Main = new Main(Color.WHITE);

和

public Main(Color c) {
   setSize(800, 600);
   setVisible(true);
   setResizable(true);
   setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
   setLocationRelativeTo(null);
   Color = c;
   setBackground(Color); 
   init();
}

编辑

您现在可以做两件事。要么让你的Color变量static像这样:

private static Color Color;

或将您的 Main 构造函数更改为

public Main() {
   setSize(800, 600);
   setVisible(true);
   setResizable(true);
   setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
   setLocationRelativeTo(null);
   Color = Color.WHITE;
   setBackground(Color); 
   init();
}