请教关于图像绘制的问题。

Question

//ImageTest.java
import java.awt.*;
import javax.swing.ImageIcon;
import javax.swing.JFrame;public class ImageTest extends JFrame {    public static void main(String[] args) {        DisplayMode displayMode;        if (args.length == 3) {
            displayMode = new DisplayMode(
                Integer.parseInt(args[0]),
                Integer.parseInt(args[1]),
                Integer.parseInt(args[2]),
                DisplayMode.REFRESH_RATE_UNKNOWN);
        }
        else {
            displayMode = new DisplayMode(800, 600, 16,
                DisplayMode.REFRESH_RATE_UNKNOWN);
        }        ImageTest test = new ImageTest();
        test.run(displayMode);
    }    private static final int FONT_SIZE = 24;
    private static final long DEMO_TIME = 3000;    private SimpleScreenManager screen;
    private Image bgImage;
    private Image opaqueImage;
    private Image transparentImage;
    private Image translucentImage;
    private Image antiAliasedImage;
    private boolean imagesLoaded;    public void run(DisplayMode displayMode) {
        setBackground(Color.blue);
        setForeground(Color.white);
        setFont(new Font("Dialog", Font.PLAIN, FONT_SIZE));
        imagesLoaded = false;        screen = new SimpleScreenManager();
        try {
            screen.setFullScreen(displayMode, this);
            loadImages();
            try {
                Thread.sleep(DEMO_TIME);
            }
            catch (InterruptedException ex) { }
        }
        finally {
            screen.restoreScreen();
        }
    }
    public void loadImages() {
        bgImage = loadImage("src/ch02src/images/background.jpg");
        opaqueImage = loadImage("src/ch02src/images/opaque.png");
        transparentImage = loadImage("src/ch02src/images/transparent.png");
        translucentImage = loadImage("src/ch02src/images/translucent.png");
        antiAliasedImage = loadImage("src/ch02src/images/antialiased.png");
        imagesLoaded = true;
        // signal to AWT to repaint this window
        repaint();
    }
    private Image loadImage(String fileName) {
        return new ImageIcon(fileName).getImage();
    }
    public void paint(Graphics g) {
        // set text anti-aliasing
        if (g instanceof Graphics2D) {
            Graphics2D g2 = (Graphics2D)g;
            g2.setRenderingHint(
                RenderingHints.KEY_TEXT_ANTIALIASING,
                RenderingHints.VALUE_TEXT_ANTIALIAS_ON);
        }        // draw images
        if (imagesLoaded) {
            g.drawImage(bgImage, 0, 0, null);
            drawImage(g, opaqueImage, 0, 0, "Opaque");
            drawImage(g, transparentImage, 320, 0, "Transparent");
            drawImage(g, translucentImage, 0, 300, "Translucent");
            drawImage(g, antiAliasedImage, 320, 300,
                "Translucent (Anti-Aliased)");
            System.out.println("drawImage");
        }
        else {
            g.drawString("Loading Images...", 5, FONT_SIZE);
            System.out.println("DrawString");
        }
    }
    public void drawImage(Graphics g, Image image, int x, int y,
        String caption)
    {
        g.drawImage(image, x, y, null);
        g.drawString(caption, x + 5, y + FONT_SIZE +
            image.getHeight(null));
    }}
//SimpleScreenManager.javaimport java.awt.*;
import javax.swing.JFrame;/**
    The SimpleScreenManager class manages initializing and
    displaying full screen graphics modes.
*/
public class SimpleScreenManager {    private GraphicsDevice device;    /**
        Creates a new SimpleScreenManager object.
    */
    public SimpleScreenManager() {
        GraphicsEnvironment environment =
            GraphicsEnvironment.getLocalGraphicsEnvironment();
        device = environment.getDefaultScreenDevice();
    }
    /**
        Enters full screen mode and changes the display mode.
    */
    public void setFullScreen(DisplayMode displayMode,
        JFrame window)
    {
        window.setUndecorated(true);
        window.setResizable(false);        device.setFullScreenWindow(window);
        if (displayMode != null &&
            device.isDisplayChangeSupported())
        {
            try {
                device.setDisplayMode(displayMode);
            }
            catch (IllegalArgumentException ex) {
                // ignore - illegal mode for this device
            }
        }
    }
    /**
        Returns the window currently used in full screen mode.
    */
    public Window getFullScreenWindow() {
        return device.getFullScreenWindow();
    }
    /**
        Restores the screen's display mode.
    */
    public void restoreScreen() {
        Window window = device.getFullScreenWindow();
        if (window != null) {
            window.dispose();
        }
        device.setFullScreenWindow(null);
    }}

Answer 1

问题1：
paint调用了3次，console打印如下：
DrawString
DrawString
drawImage
调用3次。DrawString
DrawString
drawImage
drawImage
drawImage
调用5次。
如何调用多次的。问题2：
我显示器是1280×1024的
我改displayMode = new DisplayMode(800, 600, 16,
                DisplayMode.REFRESH_RATE_UNKNOWN);
displayMode = new DisplayMode(1280, 1024, 16,
                DisplayMode.REFRESH_RATE_UNKNOWN);
图片显示反而变小了，这个地方怎么控制的？

Answer 2

你的图片load完之后
每刷新一次就会打印一次drawImage

Answer 3

方便观察
把第一个程序修改了一下
图片load结束后
窗口每重绘一次,调用一次repaint
打印drawImage
import java.awt.*;
import javax.swing.ImageIcon;
import javax.swing.JFrame;
import javax.imageio.*;
import java.io.*;public class ImageTest extends JFrame {    public static void main(String[] args) {        DisplayMode displayMode;        if (args.length == 3) {
            displayMode = new DisplayMode(
                Integer.parseInt(args[0]),
                Integer.parseInt(args[1]),
                Integer.parseInt(args[2]),
                DisplayMode.REFRESH_RATE_UNKNOWN);
        }
        else {
            displayMode = new DisplayMode(800, 600, 16,
                DisplayMode.REFRESH_RATE_UNKNOWN);
        }        ImageTest test = new ImageTest();
test.setSize(800, 800);
test.setVisible(true);//调用repaint 此时图片还未load 打印DrawString
        test.run(displayMode);//load完成 打印drawImage
    }    private static final int FONT_SIZE = 24;
    private static final long DEMO_TIME = 3000;    private SimpleScreenManager screen;
    private Image bgImage;
    private Image opaqueImage;
    private Image transparentImage;
    private Image translucentImage;
    private Image antiAliasedImage;
    private boolean imagesLoaded;    public void run(DisplayMode displayMode) {
        setBackground(Color.blue);
        setForeground(Color.white);
        setFont(new Font("Dialog", Font.PLAIN, FONT_SIZE));
        imagesLoaded = false;        screen = new SimpleScreenManager();
        try {
            //screen.setFullScreen(displayMode, this);
            loadImages();
            try {
                Thread.sleep(DEMO_TIME);
            }
            catch (InterruptedException ex) { }
        }
        finally {
            //screen.restoreScreen();
        }
    }
    public void loadImages() {
try{
bgImage = ImageIO.read(new File("01.jpg"));
opaqueImage = ImageIO.read(new File("02.png"));
transparentImage = ImageIO.read(new File("03.png"));
translucentImage = ImageIO.read(new File("04.png"));
antiAliasedImage = ImageIO.read(new File("05.png"));
imagesLoaded = true;
// signal to AWT to repaint this window
repaint();
}
catch(IOException e){e.printStackTrace();}
    }
    //private Image loadImage(String fileName) {
     //   return new ImageIcon(fileName).getImage();
    //}
    public void paint(Graphics g) {
        // set text anti-aliasing
        if (g instanceof Graphics2D) {
            Graphics2D g2 = (Graphics2D)g;
            g2.setRenderingHint(
                RenderingHints.KEY_TEXT_ANTIALIASING,
                RenderingHints.VALUE_TEXT_ANTIALIAS_ON);
        }        // draw images
        if (imagesLoaded) {
            g.drawImage(bgImage, 0, 0, null);
            drawImage(g, opaqueImage, 0, 0, "Opaque");
            drawImage(g, transparentImage, 320, 0, "Transparent");
            drawImage(g, translucentImage, 0, 300, "Translucent");
            drawImage(g, antiAliasedImage, 320, 300,
                "Translucent (Anti-Aliased)");
            System.out.println("drawImage");
        }
        else {
            g.drawString("Loading Images...", 5, FONT_SIZE);
            System.out.println("DrawString");
        }
    }
    public void drawImage(Graphics g, Image image, int x, int y,
        String caption)
    {
        g.drawImage(image, x, y, null);
        g.drawString(caption, x + 5, y + FONT_SIZE +
            image.getHeight(null));
    }}