開始Java（幫助）

Question

我正在做一個自學AP Java課程，我只需要一些快速幫助。我對paintComponent有這個問題。我總是收到消息來覆蓋它併爲它創建其他東西。這是我的代碼：

package pkghello; 

import java.awt.Graphics; 
import java.awt.Graphics2D; 
import java.awt.Rectangle; 
import javax.swing.JComponent; 

/** 
* 
* @author ap 
*/ 
public class RectangleComponent extends JComponent { 


    public void paintComponent (Graphics g) //It only highlights "paintComponent" 
    { 
     Graphics2D g2 = (Graphics2D) g; 
     // 
     Rectangle box = new Rectangle (5,10,20,30); 
     g2.draw(box); 
     box.translate(90, 90); 
     box.setSize(150,150); 
     g2.draw(box); 
    } 

} 

Answer 1

兩件事。它可能希望您添加@Override註釋，除非您確實需要它，否則應保留paintComponentprotected

例如，

@Override 
protected void paintComponent (Graphics g)