Question

我目前有一个背景图像，可以延伸到整个屏幕，前面有一个较小的图像。我希望前景图像在屏幕上移动。如果有人可以提供一个例子，或者帮助解决我的问题，那就太好了。到目前为止，我有以下代码：

    public Video(BufferedImage foreground, BufferedImage background){

        pane = this.getContentPane(); //get the content pane to place components
        pane.setLayout(null); //use absolute positioning (using Insets)

        //set up frame
        this.setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);
        this.setVisible(true);
        this.setBounds(0,0,(int)Toolkit.getDefaultToolkit().getScreenSize().getWidth(),(int)Toolkit.getDefaultToolkit().getScreenSize().getHeight());

        //set the bounds of the layered pane
        lpane.setBounds(0, 0,(int)Toolkit.getDefaultToolkit().getScreenSize().getWidth(),(int)Toolkit.getDefaultToolkit().getScreenSize().getHeight());
        this.add(lpane, BorderLayout.CENTER);

        //instantiating the panels
        this.backgroundPanel = new ImagePanel(background);
        this.foregroundPanel = new ImagePanel(foreground);
        //set bounds of the panel
        backgroundPanel.setBounds(0, 0,(int)Toolkit.getDefaultToolkit().getScreenSize().getWidth(),(int)Toolkit.getDefaultToolkit().getScreenSize().getHeight());
        //foregroundPanel.setBounds(200, 100,350,350);


        //add the panels to the layered pane
        lpane.add(this.backgroundPanel, new Integer(0), 0);
        PongPanel p = new PongPanel();
        p.setBounds(0, 0,(int)Toolkit.getDefaultToolkit().getScreenSize().getWidth(),(int)Toolkit.getDefaultToolkit().getScreenSize().getHeight());
        p.setOpaque(false);
        lpane.add(p, new Integer(1), 0);
        p.start();

//        lpane.add(foregroundPanel, new Integer(1), 0);
//        lpane.add(new KeyBidings());

//      Pong p = new Pong();
//      p.setVisible(true);
//      p.start();
        this.foregroundPanel.setLocation(500,250);
        this.waitFor(5);
        this.foregroundPanel.setLocation(250,250);

        //this.showImageAt(100,0);
//      int width = this.foregroundPanel.getBounds().width;
//      int height = this.backgroundPanel.getBounds().height;
//      for(int k=10; k<500; k++){
//          this.showImageAt(k,0);
//          this.waitFor(5);
//      }

    }

下面的类绘制一个红色的球，它在屏幕上滑动。但是，当我添加此面板时，它用白色背景填充周围空间，我看不到原始背景图像。基本上我只是希望红色球在背景图像前面的屏幕上滑动。

import java.awt.AlphaComposite;
import java.awt.Color;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.Image;
import java.awt.Toolkit;
import java.awt.event.WindowAdapter;
import java.awt.event.WindowEvent;
import java.awt.image.BufferedImage;

import javax.swing.JFrame;
import javax.swing.JPanel;

public class PongPanel extends JPanel implements Runnable
{

    int x_pos = 10;
    int y_pos = 100;
    int radius = 50;

    public PongPanel()
    {
        //Set to exit on close

//      this.addComponentListener(new WindowAdapter()
//      {
//          @Override
//          public void windowClosing(WindowEvent we)
//          {
//              System.exit(0);
//          }
//      });
        this.setSize(300, 250);
    }
    public void start()
    {
        Thread th = new Thread(this);
        th.start();
    }

    public static void main(String args[])
    {
        JFrame frame = new JFrame();
        PongPanel panel = new PongPanel();
        frame.add(panel);
        frame.setBounds(0,0,(int)Toolkit.getDefaultToolkit().getScreenSize().getWidth(),(int)Toolkit.getDefaultToolkit().getScreenSize().getHeight());
        panel.start();
        frame.setVisible(true);

    }

    @Override
    public void run()
    {

        //infini loop
        while (true)
        {
            x_pos+=1;
            repaint();

            try
            {
                //Sleep thread for 20 milliseconds
                Thread.sleep(20);
            }
            catch (InterruptedException ex)
            {
                //do nothing
            }
        }
    }

    @Override
    public void paintComponent(Graphics g) { 
        super.paintComponent(g); 
        g.drawImage(getFrame(), 0, 0, this);
    }

    private Image getFrame() {
        BufferedImage img = new BufferedImage(getWidth(), getHeight(), BufferedImage.TYPE_3BYTE_BGR);
        Graphics g = img.getGraphics();
        //g.setColor(Color.white);
        //g.fillRect(0, 0, getWidth(), getHeight());
        // Apply our own painting effect
        Graphics2D g2d = (Graphics2D) g.create();
        // 50% transparent Alpha
        g2d.setComposite(AlphaComposite.getInstance(AlphaComposite.SRC_OVER, 1f));

        g2d.setColor(getBackground());
        g2d.fill(getBounds());

        g.setColor(Color.RED);
        g.fillOval(x_pos - radius, y_pos - radius, 2 * radius, 2 * radius);
        g.dispose();
        return img;
    }
}

Answer 1

在java中不可能重叠像jlabel，jbutton等jcomponent。，为了实现组件的重叠，

将jcomponents放在JLayered窗格

上

JLayeredPane LPne = new javax.swing.JLayeredPane();

然后可以反复重叠任意数量的jcomponent，

尝试这种方式。

使用当前背景图片在屏幕上移动图片？

1 个答案: