Comment enregistrer une image à partir du panneau de dessin dans Java?

Question

C'est le code que j'ai. Je veux enregistrer l'image de tout ce que je dessine sur le pad. Il ya est un bouton «enregistrer», donc chaque fois que je vais cliquer dessus, je veux enregistrer une image du pavé de dessin . Je connais un peu le java. Aidez-moi s'il vous plaît à faire ceci.

package paint; 
import java.awt.*; 
import java.awt.event.*; 
import javax.swing.*; 

public class paint{ 
public static void main(String[] args){ 
    Icon iconB = new ImageIcon("blue.gif"); 

    Icon iconM = new ImageIcon("magenta.gif"); 

    Icon iconR = new ImageIcon("red.gif"); 

    Icon iconBl = new ImageIcon("black.gif"); 

    Icon iconG = new ImageIcon("green.gif"); 


    JFrame frame = new JFrame("Paint It"); 
    //Creates a frame with a title of "Paint it" 

    Container content = frame.getContentPane(); 
    //Creates a new container 
    content.setLayout(new BorderLayout()); 
    //sets the layout 

    final PadDraw drawPad = new PadDraw(); 
    //creates a new padDraw, which is pretty much the paint program 

    content.add(drawPad, BorderLayout.CENTER); 
    //sets the padDraw in the center 

    JPanel panel = new JPanel(); 
    //creates a JPanel 
    panel.setPreferredSize(new Dimension(32, 68)); 
    panel.setMinimumSize(new Dimension(32, 68)); 
    panel.setMaximumSize(new Dimension(32, 68)); 
    //This sets the size of the panel 

    JButton clearButton = new JButton("Clear"); 
    //creates the clear button and sets the text as "Clear" 
    clearButton.addActionListener(new ActionListener(){ 
     public void actionPerformed(ActionEvent e){ 
      drawPad.clear(); 
     } 
    }); 
    //this is the clear button, which clears the screen. This pretty 
    //much attaches an action listener to the button and when the 
    //button is pressed it calls the clear() method 

      JButton saveButton = new JButton("save"); 

    JButton redButton = new JButton(iconR); 
    //creates the red button and sets the icon we created for red 
    redButton.addActionListener(new ActionListener(){ 
     public void actionPerformed(ActionEvent e){ 
      drawPad.red(); 
     } 

    }); 
    //when pressed it will call the red() method. So on and so on =] 

    JButton blackButton = new JButton(iconBl); 
    //same thing except this is the black button 
    blackButton.addActionListener(new ActionListener(){ 
     public void actionPerformed(ActionEvent e){ 
      drawPad.black(); 
     } 
    }); 

    JButton magentaButton = new JButton(iconM); 
    //magenta button 
    magentaButton.addActionListener(new ActionListener(){ 
     public void actionPerformed(ActionEvent e){ 
      drawPad.magenta(); 
     } 
    }); 

    JButton blueButton = new JButton(iconB); 
    //blue button 
    blueButton.addActionListener(new ActionListener(){ 
     public void actionPerformed(ActionEvent e){ 
      drawPad.blue(); 
     } 
    }); 

    JButton greenButton = new JButton(iconG); 
    //green button 
    greenButton.addActionListener(new ActionListener(){ 
     public void actionPerformed(ActionEvent e){ 
      drawPad.green(); 
     } 
    }); 

    blackButton.setPreferredSize(new Dimension(16, 16)); 
    magentaButton.setPreferredSize(new Dimension(16, 16)); 
    redButton.setPreferredSize(new Dimension(16, 16)); 
    blueButton.setPreferredSize(new Dimension(16, 16)); 
    greenButton.setPreferredSize(new Dimension(16,16)); 
    //sets the sizes of the buttons 

    panel.add(greenButton); 
    panel.add(blueButton); 
    panel.add(magentaButton); 
    panel.add(blackButton); 
    panel.add(redButton); 
    panel.add(clearButton); 
      panel.add(saveButton); 
    //adds the buttons to the panel 

    content.add(panel, BorderLayout.SOUTH); 
    //sets the panel to the left 

    frame.setSize(300, 300); 
    //sets the size of the frame 
    frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); 
    //makes it so you can close 
    frame.setVisible(true); 
    //makes it so you can see it 
} 
} 


class PadDraw extends JComponent{ 
Image image; 
//this is gonna be your image that you draw on 
Graphics2D graphics2D; 
//this is what we'll be using to draw on 
int currentX, currentY, oldX, oldY; 
//these are gonna hold our mouse coordinates 

//Now for the constructors 
public PadDraw(){ 
    setDoubleBuffered(false); 
    addMouseListener(new MouseAdapter(){ 
     public void mousePressed(MouseEvent e){ 
      oldX = e.getX(); 
      oldY = e.getY(); 
     } 
    }); 
    //if the mouse is pressed it sets the oldX & oldY 
    //coordinates as the mouses x & y coordinates 
    addMouseMotionListener(new MouseMotionAdapter(){ 
     public void mouseDragged(MouseEvent e){ 
      currentX = e.getX(); 
      currentY = e.getY(); 
      if(graphics2D != null) 
      graphics2D.drawLine(oldX, oldY, currentX, currentY); 
      repaint(); 
      oldX = currentX; 
      oldY = currentY; 
     } 

    }); 
    //while the mouse is dragged it sets currentX & currentY as the mouses x and y 
    //then it draws a line at the coordinates 
    //it repaints it and sets oldX and oldY as currentX and currentY 
} 

public void paintComponent(Graphics g){ 
    if(image == null){ 
     image = createImage(getSize().width, getSize().height); 
     graphics2D = (Graphics2D)image.getGraphics(); 
     graphics2D.setRenderingHint(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON); 
     clear(); 

    } 
    g.drawImage(image, 0, 0, null); 
} 
//this is the painting bit 
//if it has nothing on it then 
//it creates an image the size of the window 
//sets the value of Graphics as the image 
//sets the rendering 
//runs the clear() method 
//then it draws the image 


public void clear(){ 
    graphics2D.setPaint(Color.white); 
    graphics2D.fillRect(0, 0, getSize().width, getSize().height); 
    graphics2D.setPaint(Color.black); 
    repaint(); 
} 
//this is the clear 
//it sets the colors as white 
//then it fills the window with white 
//thin it sets the color back to black 
public void red(){ 
    graphics2D.setPaint(Color.red); 
    repaint(); 
} 
//this is the red paint 
public void black(){ 
    graphics2D.setPaint(Color.black); 
    repaint(); 
} 
//black paint 
public void magenta(){ 
    graphics2D.setPaint(Color.magenta); 
    repaint(); 
} 
//magenta paint 
public void blue(){ 
    graphics2D.setPaint(Color.blue); 
    repaint(); 
} 
//blue paint 
public void green(){ 
    graphics2D.setPaint(Color.green); 
    repaint(); 
} 
//green paint 

}

Answer 1

Les bases pour la création d'une image de tout composant Swing est utilisé:

BufferedImage image = new BufferedImage(component.getWidth(), component.getHeight(), BufferedImage.TYPE_INT_RGB); 
Graphics2D g2d = image.createGraphics(); 
component.print(g2d); 
g2d.dispose(); 

Vous pouvez alors enregistrer la "image" en utilisant ImageIO.

Ou vous pouvez utiliser le Screen Image qui a des fonctionnalités supplémentaires à:

composants transparents poignée
2. créer une image d'une zone du composant
3. créer une image d'un composant non affiché sur un fenêtre visible
4. écriture à l'image dans un fichier

Answer 2

J'ai écrit la méthode save() copiez-le dans la classe PadDraw et appelez save() chaque fois que vous avez besoin de sauvegarder l'image.

public void save(){ 
    try { 
     BufferedImage bimage = new BufferedImage(image.getWidth(null), image.getHeight(null), BufferedImage.TYPE_INT_ARGB); 

     // Draw the image on to the buffered image 
     Graphics2D bGr = bimage.createGraphics(); 
     bGr.drawImage(image, 0, 0, null); 
     javax.imageio.ImageIO.write(bimage , "PNG", new File("test.png")); 
     bGr.dispose(); 
    } catch (Exception ex) { 
     Logger.getLogger(PadDraw.class.getName()).log(Level.SEVERE, null, ex); 
    } 
}