桌面截圖功能

import javax.swing.*;
import java.awt.*;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.MouseAdapter;
import java.awt.event.MouseEvent;
import java.awt.event.MouseMotionListener;

/**
?* 用Java模擬出QQ桌面截圖功能
?*/

public class Test extends JFrame {

?private static final long serialVersionUID = -267804510087895906L;

?private JButton button = null;
?
?private JLabel imgLabel = null;

?public Test() {
??button = new JButton("模擬屏幕（點右鍵退出）");
??button.addActionListener(new ActionListener() {
???public void actionPerformed(ActionEvent e) {
????try {
?????new ScreenWindow(imgLabel);
????} catch (Exception e1) {
?????JOptionPane.showConfirmDialog(null, "出現意外錯誤！", "系統提示", JOptionPane.DEFAULT_OPTION, JOptionPane.ERROR_MESSAGE);
????}
???}
??});
??JPanel pane = new JPanel();
??pane.setBackground(Color.WHITE);
??imgLabel = new JLabel();
??pane.add(imgLabel);
??JScrollPane spane = new JScrollPane(pane);
??this.getContentPane().add(button, BorderLayout.NORTH);
??this.getContentPane().add(spane);
??this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
??this.setSize(300, 200);
??this.setLocationRelativeTo(null);
??this.setVisible(true);
?}

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

class ScreenWindow extends JFrame {

?private static final long serialVersionUID = -3758062802950480258L;
?
?private boolean isDrag = false;

?private int x = 0;

?private int y = 0;

?private int xEnd = 0;

?private int yEnd = 0;

?public ScreenWindow(final JLabel imgLabel) throws AWTException, InterruptedException {
??Dimension screenDims = Toolkit.getDefaultToolkit().getScreenSize();
??JLabel label = new JLabel(new ImageIcon(ScreenImage.getScreenImage(0, 0, screenDims.width, screenDims.height)));
??label.setCursor(new Cursor(Cursor.CROSSHAIR_CURSOR));
??label.addMouseListener(new MouseAdapter() {
???public void mouseClicked(MouseEvent e) {
????if (e.getButton() == MouseEvent.BUTTON3) {
?????dispose();
????}
???}

???public void mousePressed(MouseEvent e) {
????x = e.getX();
????y = e.getY();
???}

???public void mouseReleased(MouseEvent e) {
????if (isDrag) {
?????xEnd = e.getX();
?????yEnd = e.getY();
?????if(x > xEnd){
??????int temp = x;
??????x = xEnd;
??????xEnd = temp;
?????}
?????if(y > yEnd){
??????int temp = y;
??????y = yEnd;
??????yEnd = temp;
?????}
?????try {
??????imgLabel.setIcon(new ImageIcon(ScreenImage.getScreenImage(x, y, xEnd - x, yEnd - y)));
?????} catch (Exception ex) {
??????JOptionPane.showConfirmDialog(null, "出現意外錯誤！", "系統提示", JOptionPane.DEFAULT_OPTION, JOptionPane.ERROR_MESSAGE);
?????}
?????dispose();
????}
???}
??});
??label.addMouseMotionListener(new MouseMotionListener() {
???public void mouseDragged(MouseEvent e) {
????if(!isDrag)
?????isDrag = true;
???}

???public void mouseMoved(MouseEvent e) {
????/** 拖動過程的虛線選取框需自己實現 */
???}
??});
??this.setUndecorated(true);
??this.getContentPane().add(label);
??this.setSize(screenDims.width, screenDims.height);
??this.setVisible(true);
??this.setExtendedState(JFrame.MAXIMIZED_BOTH);
?}
}

class ScreenImage {

?public static Image getScreenImage(int x, int y, int w, int h) throws AWTException, InterruptedException {
??Robot robot = new Robot();
??Image screen = robot.createScreenCapture(new Rectangle(x, y, w, h)).getScaledInstance(w, h, Image.SCALE_SMOOTH);
??MediaTracker tracker = new MediaTracker(new Label());
??tracker.addImage(screen, 1);
??tracker.waitForID(0);
??return screen;
?}
}

截屏

public class GuiCamera {
?private String fileName; //文件的前綴

?private String defaultName = "GuiCamera";

?static int serialNum = 0;

?private String imageFormat; //圖像文件的格式

?private String defaultImageFormat = "png";

?Dimension d = Toolkit.getDefaultToolkit().getScreenSize();

?/****************************************************************
? * 默認的文件前綴為GuiCamera，文件格式為PNG格式
? * The default construct will use the default?
? * Image file surname "GuiCamera",?
? * and default image format "png"
? ****************************************************************/
?public GuiCamera() {
??fileName = defaultName;
??imageFormat = defaultImageFormat;

?}

?/****************************************************************
? * @param s the surname of the snapshot file
? * @param format the format of the? image file,?
? * it can be "jpg" or "png"
? * 本構造支持JPG和PNG文件的存儲
? ****************************************************************/
?public GuiCamera(String s, String format) {

??fileName = s;
??imageFormat = format;
?}

?/****************************************************************
? * 對屏幕進行拍照
? * snapShot the Gui once
? ****************************************************************/
?public void snapShot() {

??try {
???//拷貝屏幕到一個BufferedImage對象screenshot
???BufferedImage screenshot = (new Robot())
?????.createScreenCapture(new Rectangle(0, 0,
???????(int) d.getWidth(), (int) d.getHeight()));
???serialNum++;
???//根據文件前綴變量和文件格式變量，自動生成文件名
???String name = fileName + String.valueOf(serialNum) + "."
?????+ imageFormat;
???File f = new File(name);
???System.out.print("Save File " + name);
???//將screenshot對象寫入圖像文件
???ImageIO.write(screenshot, imageFormat, f);
???System.out.print("..Finished!\n");
??} catch (Exception ex) {
???System.out.println(ex);
??}
?}

?public static void main(String[] args) {
??GuiCamera cam = new GuiCamera("d:\\Hello", "png");//

??cam.snapShot();
?}
}

透明窗體
public class TransparentBackground extends JComponent implements
??ComponentListener, WindowFocusListener, Runnable {
?private JFrame frame;

?private Image background;

?private long lastupdate = 0;

?public boolean refreshRequested = true;

?public TransparentBackground(JFrame frame) {
??this.frame = frame;
??updateBackground();
??frame.addComponentListener(this);
??frame.addWindowFocusListener(this);
??new Thread(this).start();
?}

?public void componentShown(ComponentEvent evt) {
??repaint();
?}

?public void componentResized(ComponentEvent evt) {
??repaint();
?}

?public void componentMoved(ComponentEvent evt) {
??repaint();
?}

?public void componentHidden(ComponentEvent evt) {
?}

?public void windowGainedFocus(WindowEvent evt) {
??refresh();
?}

?public void windowLostFocus(WindowEvent evt) {
?? refresh();
?}

?public void refresh() {
??if (frame.isVisible()) {
???repaint();
???refreshRequested = true;
???lastupdate = new Date().getTime();
??}
?}

?public void run() {
??try {
???while (true) {
????Thread.sleep(250);
????long now = new Date().getTime();
????if (refreshRequested && ((now - lastupdate) > 1000)) {
?????if (frame.isVisible()) {
??????Point location = frame.getLocation();
//??????frame.setVisible(false);
??????updateBackground();
//??????frame.setVisible(true);
??????frame.setLocation(location);
??????refresh();
?????}
?????lastupdate = now;
?????refreshRequested = false;
????}
???}
??} catch (Exception ex) {
???ex.printStackTrace();
??}
?}

?public static void main(String[] args) {
??JFrame frame = new JFrame("Transparent Window");
??frame.setUndecorated(true);

??TransparentBackground bg = new TransparentBackground(frame);
??// bg.snapBackground();
??bg.setLayout(new BorderLayout());

??JPanel panel = new JPanel() {
???public void paintComponent(Graphics g) {
????g.setColor(Color.blue);
????Image img = new ImageIcon("d:/moon.gif").getImage();
????g.drawImage(img, 150, 150, null);
???//?g.drawLine(0,0, 600, 500);
???}
??};
??panel.setOpaque(false);
??JLabel jl=new JLabel(new ImageIcon("d:/moon.gif"));
??
??
??bg.add("North", jl);
??bg.add("Center", panel);

??frame.getContentPane().add("Center", bg);
??frame.pack();
??Toolkit tk = Toolkit.getDefaultToolkit();
??Dimension dim = tk.getScreenSize();
??frame.setSize((int) dim.getWidth(), (int) dim.getHeight());
??frame.setLocationRelativeTo(null);
??frame.show();
?}

?public void updateBackground() {
??try {
???Robot rbt = new Robot();
???Toolkit tk = Toolkit.getDefaultToolkit();
???Dimension dim = tk.getScreenSize();
???background = rbt.createScreenCapture(new Rectangle(0, 0, (int) dim
?????.getWidth(), (int) dim.getHeight()));
??} catch (Exception ex) {
???// p(ex.toString( ));
???// 此方法沒有申明過，因為無法得知上下文。因為不影響執行效果，先注釋掉它
???ex.printStackTrace();
??}
?}

?public void paintComponent(Graphics g) {
??Point pos = this.getLocationOnScreen();
??Point offset = new Point(-pos.x, -pos.y);
??g.drawImage(background, offset.x, offset.y, null);
?}
}