Java面板/幀圖形不能正常工作

Question

我正在嘗試使用Java Graphics進行人生模擬遊戲，但是當運行我的代碼時，屏幕的左邊三分之一是灰色的。我希望整個屏幕都是白色的黑色方塊代表生活廣場。我對所有的java容器/面板和框架感到困惑。

這裏是我的代碼：

public class ConwayGame { 
static JPanel panel; 
static JFrame frame; 
public static void main(String[] args) throws InterruptedException{ 
    int [][] array = new int [40][40]; 
    /* 
    * Set the pattern for Conway's Game of Life by manipulating the array below. 
    */ 

    /*Acorn 
    */ 
    array[19][15]=1; 
    array[19][16]=1; 
    array[19][19]=1; 
    array[19][20]=1; 
    array[19][21]=1; 
    array[18][18]=1; 
    array[17][16]=1; 

    panel = new JPanel(); 
    Dimension dim = new Dimension(400, 400); 
    panel.setPreferredSize(dim); 
    frame = new JFrame(); 
    frame.setSize(400,400); 
    Container contentPane = frame.getContentPane(); 
    contentPane.add(panel); 
    frame.setVisible(true); 

    /* 
    * Runs the Game of Life simulation "a" number of times. 
    */ 



     Graphics g = panel.getGraphics(); 

    drawArray(array, g); 

     //paint(g); 
     //Thread.sleep(125); 
     //g.dispose(); 

} 














/* 
* Creates the graphic for Conway's game of life. 
*/ 
public static void drawArray(int[][] array, Graphics g) { 
    int BOX_DIM = 10; 
    for (int i = 0; i < array.length; i++) { 
     for (int j = 0; j < array[0].length; j++) { 
      g.drawRect(i * BOX_DIM, j * BOX_DIM, 10, 10); 
      if (array[i][j] == 0) { 
       g.setColor(Color.WHITE); 
       g.fillRect(i * BOX_DIM, j * BOX_DIM, 10, 10); 
      } 
      if (array[i][j] == 1) { 
       g.setColor(Color.BLACK); 
       g.fillRect(i * BOX_DIM, j * BOX_DIM, 10, 10); 
      } 
     } 
    } 

} 
} 

這裏是產生什麼樣的圖片：

Answer 1

切勿使用Graphics g = panel.getGraphics(); EVER。這不是定製繪畫在Swing中的工作原理。看看Painting in AWT and Swing和Performing Custom Painting關於繪畫是如何工作的

例如更多詳情...

import java.awt.Color; 
import java.awt.Container; 
import java.awt.Dimension; 
import java.awt.Graphics; 
import javax.swing.JFrame; 
import javax.swing.JPanel; 

public class ConwayGame { 

    static JPanel panel; 
    static JFrame frame; 

    public static void main(String[] args) throws InterruptedException { 
     int[][] array = new int[40][40]; 

     array[19][15] = 1; 
     array[19][16] = 1; 
     array[19][19] = 1; 
     array[19][20] = 1; 
     array[19][21] = 1; 
     array[18][18] = 1; 
     array[17][16] = 1; 

     panel = new JPanel() { 
      @Override 
      public Dimension getPreferredSize() { 
       return new Dimension(400, 400); 
      } 

      @Override 
      protected void paintComponent(Graphics g) { 
       super.paintComponent(g); 
       drawArray(array, g); 
      } 


     }; 
     frame = new JFrame(); 
     frame.add(panel); 
     frame.pack(); 
     frame.setVisible(true); 
    } 

    /* 
    * Creates the graphic for Conway's game of life. 
    */ 
    public static void drawArray(int[][] array, Graphics g) { 
     int BOX_DIM = 10; 
     for (int i = 0; i < array.length; i++) { 
      for (int j = 0; j < array[0].length; j++) { 
       g.drawRect(i * BOX_DIM, j * BOX_DIM, 10, 10); 
       if (array[i][j] == 0) { 
        g.setColor(Color.WHITE); 
        g.fillRect(i * BOX_DIM, j * BOX_DIM, 10, 10); 
       } 
       if (array[i][j] == 1) { 
        g.setColor(Color.BLACK); 
        g.fillRect(i * BOX_DIM, j * BOX_DIM, 10, 10); 
       } 
      } 
     } 

    } 
} 

現在，就個人而言，我將創建一個自定義組件，它從JPanel延長並將所有你需要的邏輯放入該類