Image scaling through a stream - JAVA

Question

Say I have an image. I put the image in a JPanel and add a JPanel inside a JFrame. The image moves from the bottom of the frame to the top of the frame, and its size is also reduced with AffineTransform. The variable is changed using a stream.

So here is the following code:

public class SplashScreen extends JFrame{
    Image img1;
    int w=1,h=1;
    int x=0,y=0;
    Thread th = new Thread(new Runnable() {
    @Override
    public void run() {
        while(true){
            w-=0.05;
            h-=0.05;
            y-=2;
            x+=1;

            if(y==-100){
                new MainMenu_BlueJay().setVisible(true);
                dispose();
            }

            repaint();
            try {
                Thread.sleep(10);
            } catch (InterruptedException ex) {
                Logger.getLogger(SplashScreen.class.getName()).log(Level.SEVERE, null, ex);
            }

        }
    }
});

JPanel p = new JPanel();

public SplashScreen(){
    setLayout(new BorderLayout());

    p.setPreferredSize(new Dimension(900,600));
    p.setBackground(Color.black);
    p.setLayout(new GridLayout());

    add(p);
    setTitle("BlueJay");
    setSize(900,600);

    getContentPane().setBackground(Color.black);
    setDefaultCloseOperation(EXIT_ON_CLOSE);
    setLocationRelativeTo(null);
    setVisible(true);
    th.start();
    requestFocus();
    setFocusable(true);
}

@Override
public void paint(Graphics g) {
    super.paint(g);
    Graphics2D g2d = (Graphics2D) g;

    img1 = new ImageIcon("images/Intro/BJ Production 2013.png").getImage();
    AffineTransform at = new AffineTransform();
    at.scale(w,h);
    g2d.setTransform(at);
    g2d.drawImage(img1, x, y, p);
}

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

However, what I get from the code above is just a black screen. What's the matter? In any case, if I do not use the function AffineTransform(just move it from bottom to top), the image will be displayed and moved, but the frame will flicker (blink) quickly.

Any idea to solve this problem so that I can move the image, reducing its size, as well as solving the flickering / fast blinking frame?

Answer 1

paint JFrame. - , , JPanel, paintComponent.

. . ONCE, , .

Graphics2D#setTransform(). JavaDoc http://docs.oracle.com/javase/7/docs/api/java/awt/Graphics2D.html#setTransform%28java.awt.geom.AffineTransform%29,

.

w h. ? AffineTransform . int, - w-=0.05 .

, , .

:

"" , ; -)

, snippet :

package stackoverflow;

import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.Image;

import javax.swing.ImageIcon;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.SwingUtilities;

public class SplashScreen extends JFrame
{
    public static void main(String[] args) 
    {
        SwingUtilities.invokeLater(new Runnable()
        {
            @Override
            public void run()
            {
                new SplashScreen();
            }
        });
    }    

    private PaintPanel paintPanel;

    public SplashScreen()
    {
        setTitle("BlueJay");
        setDefaultCloseOperation(EXIT_ON_CLOSE);

        getContentPane().setBackground(Color.BLACK);
        getContentPane().setLayout(new BorderLayout());

        paintPanel = new PaintPanel();
        getContentPane().add(paintPanel, BorderLayout.CENTER);

        setSize(900,600);
        setLocationRelativeTo(null);
        setFocusable(true);
        requestFocus();
        setVisible(true);

        startAnimation();
    }

    void startAnimation()
    {
        Thread thread = new Thread(new Runnable()
        {
            int x = 100;
            int y = 100;
            int w = 0;
            int h = 0;

            @Override
            public void run()
            {
                try
                {
                    Thread.sleep(500);
                }
                catch (InterruptedException ex)
                {
                    Thread.currentThread().interrupt();
                    return;
                }

                while (true)
                {
                    if (y == 200)
                    {
                        // new MainMenu_BlueJay().setVisible(true);
                        dispose();
                    }

                    x += 2;
                    y += 1;
                    w += 1;
                    h += 1;
                    paintPanel.setImageCoordinates(x, y, w, h);

                    repaint();
                    try
                    {
                        Thread.sleep(10);
                    }
                    catch (InterruptedException ex)
                    {
                        Thread.currentThread().interrupt();
                        return;
                    }

                }
            }
        });
        thread.start();
    }
}


class PaintPanel extends JPanel
{
    private final Image image;
    private int imageX, imageY;
    private int imageW, imageH;

    PaintPanel()
    {
        image = new ImageIcon("Clipboard02.jpg").getImage();
        imageX = 0;
        imageY = 0;
        imageW = 0;
        imageH = 0;
    }

    void setImageCoordinates(int imageX, int imageY, int imageW, int imageH)
    {
        this.imageX = imageX;
        this.imageY = imageY;
        this.imageW = imageW;
        this.imageH = imageH;
        repaint();
    }

    @Override
    protected void paintComponent(Graphics gr)
    {
        super.paintComponent(gr);
        Graphics2D g = (Graphics2D) gr;

        float scalingX = (float) imageW / image.getWidth(null);
        float scalingY = (float) imageH / image.getHeight(null);
        g.scale(scalingX, scalingY);

        int ix = (int)(imageX / scalingX);
        int iy = (int)(imageY / scalingY);
        g.drawImage(image, ix, iy, null);
    }
}

Answer 2

• , JFrame. JPanel paintComponent super.paintComponent
• Thread.sleep(). javax.swing.Timer.
• EDT
• new ImageIcon paint. ImageIcon , repaint(). .

.

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

public class SplashScreen extends JFrame {

    Image img1;
    int w = 900, h = 600;
    int x = 0, y = 0;

    public SplashScreen() {

        setLayout(new BorderLayout());

        add(new MyPanel());
        setTitle("BlueJay");
        setSize(900, 600);

        getContentPane().setBackground(Color.black);
        setDefaultCloseOperation(EXIT_ON_CLOSE);
        setLocationRelativeTo(null);
        setVisible(true);

        requestFocus();
        setFocusable(true);

    }

    private class MyPanel extends JPanel {

        public MyPanel() {
            img1 = new ImageIcon(SplashScreen.class.getResource("/resources/stackoverflow5.png")).getImage();
            setBackground(Color.black);
            setLayout(new GridLayout());
            Timer timer = new Timer(20, new ActionListener() {
                @Override
                public void actionPerformed(ActionEvent e) {
                    w -= 5;
                    h -= 5;
                    y -= 2;
                    x += 1;

                    if (y == -250) {
                        new MainMenu_BlueJay().setVisible(true);
                        dispose();
                    }
                    repaint();
                }
            });
            timer.start();
        }

        @Override
        public void paintComponent(Graphics g) {
            super.paintComponent(g);
            Graphics2D g2d = (Graphics2D) g;

            //AffineTransform at = new AffineTransform();
            // at.scale(w, h);
            // g2d.setTransform(at);
            g2d.drawImage(img1, x, y, w, h, this);
        }

        @Override
        public Dimension getPreferredSize() {
            return new Dimension(900, 600);
        }
    }

    public static void main(String[] args) {
        SwingUtilities.invokeLater(new Runnable() {
            @Override
            public void run() {
                new SplashScreen();
            }
        });

    }
}

Graphics2D, AffirmTransformation, .