SWing放大镜

 

package Magnifier;import java.awt.*;import java.awt.event.*;import javax.swing.*;public class Magnifier extends JFrame{    private Container container = getContentPane();        private int setCoordinateX;    private int setCoordinateY;    private int absoluteCoordinateX;    private int absoluteCoordinateY;    private int relativeCoordinateXWhenMousePressed;    private int relativeCoordinateYWhenMousePressed;    //标记鼠标是否按下。如果按下则为true，否则为false    private boolean mousePressedNow;    // 放大镜尺寸    private int magnifierSize = 200;    //放大镜内容面板    private MagnifierPanel magnifierPanel = new MagnifierPanel(magnifierSize);    //这个窗体就是放大镜 你可以自己更改这个窗体..    public Magnifier()     {       setUndecorated(true); // 这个就是窗口的边缘 false的话就失效果了       setResizable(false);        container.add(magnifierPanel);       addMouseListener(new MouseFunctions());       addMouseMotionListener(new MouseMotionFunctions());       updateSize(magnifierSize);       this.setVisible(true);     }    public static void main(String arg[])     {    // JFrame      Magnifier magnifier = new Magnifier();     magnifier.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);     }        public void updateSize(int magnifierSize)     {        magnifierPanel.setMagnifierSize(magnifierSize + 100);        setSize(magnifierSize + 100, magnifierSize + 100);        validate();     }    private class MouseFunctions extends MouseAdapter     {    public void mousePressed(MouseEvent e)     {        if (e.getClickCount() == 1)         {// 如果鼠标左键点了一下，说明按住了窗体         mousePressedNow = true;         relativeCoordinateXWhenMousePressed = e.getX();         relativeCoordinateYWhenMousePressed = e.getY();         }     }    public void mouseReleased(MouseEvent e)     {         mousePressedNow = false;     }    }    private class MouseMotionFunctions extends MouseMotionAdapter     {     public void mouseDragged(MouseEvent e)     {      if (mousePressedNow == true)      {// 如果此时鼠标按下了，说明在拖拽窗体       absoluteCoordinateX = Magnifier.this          .getLocationOnScreen().x           + e.getX();       absoluteCoordinateY = Magnifier.this        .getLocationOnScreen().y        + e.getY();       setCoordinateX = absoluteCoordinateX        - relativeCoordinateXWhenMousePressed;       setCoordinateY = absoluteCoordinateY            - relativeCoordinateYWhenMousePressed;       magnifierPanel.setMagnifierLocation(setCoordinateX,            setCoordinateY);       setLocation(setCoordinateX, setCoordinateY);      }     }     }}class MagnifierPanel extends JPanel{    private Image screenImage;    private int magnifierSize;    private int locationX;    private int locationY;    private Robot robot;     public MagnifierPanel(int magnifierSize)     {       try          {            robot = new Robot();          }       catch (AWTException e){       }            screenImage = robot.createScreenCapture(new Rectangle(0, 0, Toolkit         .getDefaultToolkit().getScreenSize().width, Toolkit         .getDefaultToolkit().getScreenSize().height));            this.magnifierSize = magnifierSize;     }    public void setMagnifierLocation(int locationX, int locationY)     {    //X坐标     this.locationX = locationX;    //Y坐标     this.locationY = locationY;     repaint();        // 注意重画控件     }    public void setMagnifierSize(int magnifierSize)     {     this.magnifierSize = magnifierSize;     }    public void paintComponent(Graphics g)     {     super.paintComponent((Graphics2D) g);    // 关键处理代码     g.drawImage(       screenImage,                 // 要画的图片       0,                    // 目标矩形的第一个角的x坐标            0,                    // 目标矩形的第一个角的y坐标       magnifierSize,                 // 目标矩形的第二个角的x坐标       magnifierSize,                 // 目标矩形的第二个角的y坐标       locationX + (magnifierSize / 4),     // 源矩形的第一个角的x坐标       locationY + (magnifierSize / 4),    // 源矩形的第一个角的y坐标       locationX + (magnifierSize / 4 * 3),     // 源矩形的第二个角的x坐标       locationY + (magnifierSize / 4 * 3),     // 源矩形的第二个角的y坐标       this     );   }}