java中怎么让图片随着窗口的大小一起改变

java中如何让图片随着窗口的大小一起改变
java中如何让窗口的背景图片随着窗口的大小一起改变？

[解决办法]
以下是SWT的实现

Java code

import java.io.InputStream;import org.eclipse.swt.SWT;import org.eclipse.swt.events.PaintEvent;import org.eclipse.swt.events.PaintListener;import org.eclipse.swt.graphics.Image;import org.eclipse.swt.graphics.ImageData;import org.eclipse.swt.graphics.Rectangle;import org.eclipse.swt.layout.FillLayout;import org.eclipse.swt.widgets.Composite;import org.eclipse.swt.widgets.Display;import org.eclipse.swt.widgets.Shell;/** * 可设置背景图片的Composite * Composite本身是可以设置背景图片的，但是只提供了平铺的显示方式，该类实现了居中、平铺和拉伸三种显示方式。 *  * @author 003 */public class ImageComposite extends Composite{    /**     * 居中     */    public static final String CENTRE = "Centre";        /**     * 平铺     */    public static final String TILED = "Tiled";    /**     * 拉伸     */    public static final String SCALED = "Scaled";    /**     * 背景图片     */    private Image backgroundImage;        /**     * 背景图片显示模式     */    private String imageDisplayMode;    /**     * 背景图片显示模式索引（引入此属性有助于必要时扩展）     */    private int modeIndex;    /**     * 构造一个没有背景图片的ImageComposite     * @param parent 父组件     * @param style 风格     */    public ImageComposite(Composite parent, int style)    {        this(parent, style, null, CENTRE);    }        /**     * 构造一个具有指定背景图片和指定显示模式的ImageComposite     * @param parent 父组件     * @param style 风格     * @param image 背景图片     * @param modeName 背景图片显示模式     */    public ImageComposite(Composite parent, int style, Image image, String modeName)    {        super(parent, style);        addPaintListener(new PaintListener()        {            @Override            public void paintControl(PaintEvent e)            {                drawImage(e);            }        });        setBackgroundImage(image);        setImageDisplayMode(modeName);    }    /**     * 获取背景图片     * @return 背景图片     * @see org.eclipse.swt.widgets.Control#getBackgroundImage(Image)     */    @Override    public Image getBackgroundImage()    {        return backgroundImage;    }    /**     * 设置背景图片     * @param 背景图片     * @see org.eclipse.swt.widgets.Control#setBackgroundImage(Image)     */    @Override    public void setBackgroundImage(Image backgroundImage)    {        this.backgroundImage = backgroundImage;        this.redraw();    }    /**     * 获取背景图片显示模式     * @return 显示模式     */    public String getImageDisplayMode()    {        return imageDisplayMode;    }    /**     * 设置背景图片显示模式     * @param modeName 模式名称，取值仅限于ImagePane.TILED  ImagePane.SCALED  ImagePane.CENTRE     */    public void setImageDisplayMode(String modeName)    {        if(modeName != null)        {            modeName = modeName.trim();                        //居中            if(modeName.equalsIgnoreCase(CENTRE))            {                this.imageDisplayMode = CENTRE;                modeIndex = 0;            }            //平铺            else if(modeName.equalsIgnoreCase(TILED))            {                this.imageDisplayMode = TILED;                modeIndex = 1;            }            //拉伸            else if(modeName.equalsIgnoreCase(SCALED))            {                this.imageDisplayMode = SCALED;                modeIndex = 2;            }                        this.redraw();        }    }        /**     * 绘制背景     * @param e PaintEvent     */    private void drawImage(PaintEvent e)    {        //如果设置了背景图片则显示        if(backgroundImage != null)        {            int width = this.getSize().x;            int height = this.getSize().y;            int imageWidth = backgroundImage.getImageData().width;            int imageHeight = backgroundImage.getImageData().height;                        switch(modeIndex)            {                //居中                case 0:                {                    int x = (width - imageWidth) / 2;                    int y = (height - imageHeight) / 2;                    e.gc.drawImage(backgroundImage, x, y);                    break;                }                //平铺                case 1:                {                    for(int ix = 0; ix < width; ix += imageWidth)                    {                        for(int iy = 0; iy < height; iy += imageHeight)                        {                            e.gc.drawImage(backgroundImage, ix, iy);                        }                    }                                        break;                }                //拉伸                case 2:                {                    ImageData data = backgroundImage.getImageData().scaledTo(width, height);                    e.gc.drawImage(new Image(e.display, data), 0, 0);                    break;                }            }        }    }        /**     * 设置窗口位于屏幕中间     * @param display 设备     * @param shell 要调整位置的窗口对象     */    public static void center(Display display, Shell shell)    {        Rectangle bounds = display.getPrimaryMonitor().getBounds();        Rectangle rect = shell.getBounds();        int x = bounds.x + (bounds.width - rect.width) / 2;        int y = bounds.y + (bounds.height - rect.height) / 2;        shell.setLocation(x, y);    }        public static void main(String[] args)    {        Display display = Display.getDefault();        InputStream is = ImageComposite.class.getResourceAsStream("test.jpg");        Image image = new Image(display, new ImageData(is));        Shell shell = new Shell();        new ImageComposite(shell, SWT.NONE, image, ImageComposite.SCALED);        shell.setText("ImageComposite Test");        shell.setLayout(new FillLayout());        shell.setSize(800, 600);        center(display, shell);        shell.open();        shell.layout();                while(!shell.isDisposed())        {            if(!display.readAndDispatch())            {                display.sleep();            }        }        display.dispose();    }}