如何在屏幕上繪製圖像？

Question

我想使用paint方法將圖像添加到屏幕上？我不想使用JLabel，因爲我想自己設置位置。

Board.class：

public class Board extends JPanel{ 
    BufferedImage image; 

public Board() { 
    try { 
     image = ImageIO.read(new File("C:\\Users\\alexa_000\\Pictures\\RocketShip.png")); 
    }catch(IOException e) { 
     e.printStackTrace(); 
    } 
} 
protected void paintComponent(Graphics g) { 
    super.paintComponents(g); 
    g.drawImage(image, 0, 0, this); 
} 
public Dimension getPreferredSize() { 
    return new Dimension(image.getWidth(),image.getHeight()); 
} 

} 

RType.class：

public class RType extends JFrame{ 
    public static void main(String[] args) { 
     SwingUtilities.invokeLater(new Runnable() { 
      @Override 
      public void run() { 
       JFrame frame = new JFrame(); 
       frame.setDefaultCloseOperation(EXIT_ON_CLOSE); 
       Panel panel = new Panel(); 
       frame.setContentPane(panel); 
       frame.setSize(800,600); 
       frame.setLocationRelativeTo(null); 
       frame.setVisible(true); 
     } 
    }); 
} 
} 

Answer 1

你有這麼多的錯誤，我不知道，甚至從哪裏開始......而不是在JLabel顯示圖像的你可以在一些容器上顯示你的圖像。像JPanel。 這是一個小型演示，演示如何在JPanel上顯示圖像。代碼中的解釋。

import javax.imageio.ImageIO; 
import javax.swing.*; 
import java.awt.*; 
import java.awt.image.BufferedImage; 
import java.io.File; 
import java.io.IOException; 

//No need to extend your class with JFrame 
public class Board { 

    public static void main(String[] args) { 
     SwingUtilities.invokeLater(new Runnable() { 
      @Override 
      public void run() { 
       JFrame frame = new JFrame(); 
       frame.setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE); 
       //Instantiate Panel class. 
       Panel panel = new Panel(); 
       //Set instance of Panel class as a content pane for your JFrame 
       frame.setContentPane(panel); 
       //Avoid calling setSize. Call pack instead 
       frame.pack(); 
       //If you want to position your frame on center of screen, no need 
       //for fancy calculations. This is how you can do it. 
       frame.setLocationRelativeTo(null); 
       frame.setVisible(true); 
      } 
     }); 

    } 

    /*Image will be displayed on JPanel*/ 
    private static class Panel extends JPanel { 
     BufferedImage image; 

     public Panel() { 
      try { 
       //String you are passing in "new File()" is a path to your image 
       image = ImageIO.read(new File("path-to-your-image")); 
      } catch (IOException e) { 
       e.printStackTrace(); 
      } 
     } 

     /*Override this method to display graphics on JPanel. 
     * Do not override paint method!*/ 
     @Override 
     protected void paintComponent(Graphics g) { 
      super.paintComponent(g); 
      g.drawImage(image,0,0,this); 

     } 

     /*Override getPreferredSize method so it returns dimensions of your image. 
     * Size of your container (Panel) will be equal to size of that image*/ 
     @Override 
     public Dimension getPreferredSize() { 
      return new Dimension(image.getWidth(),image.getHeight()); 
     } 
    } 
}