java编程实现屏幕截图(截屏)代码总结
作者:阮斯哲(技术-2273)
这篇文章主要介绍了java编程实现屏幕截图(截屏)代码,结合3个实例总结分析了Java截屏时页面抓取及图片保存的相关技巧,具有一定参考借鉴价值,需要的朋友可以参考下
本文实例总结了常见的java编程实现屏幕截图方法。分享给大家供大家参考,具体如下:
方法一:
import java.awt.Desktop; import java.awt.Dimension; import java.awt.Rectangle; import java.awt.Robot; import java.awt.Toolkit; import java.awt.image.BufferedImage; import java.io.File; import javax.imageio.ImageIO; public class CaptureScreen { public static void captureScreen(String fileName, String folder) throws Exception { Dimension screenSize = Toolkit.getDefaultToolkit().getScreenSize(); Rectangle screenRectangle = new Rectangle(screenSize); Robot robot = new Robot(); BufferedImage image = robot.createScreenCapture(screenRectangle); //保存路径 File screenFile = new File(fileName); if (!screenFile.exists()) { screenFile.mkdir(); } File f = new File(screenFile, folder); ImageIO.write(image, "png", f); //自动打开 if (Desktop.isDesktopSupported() && Desktop.getDesktop().isSupported(Desktop.Action.OPEN)) Desktop.getDesktop().open(f); } public static void main(String[] args) { try { captureScreen("e:\\你好","11.png"); } catch (Exception e) { // TODO Auto-generated catch block e.printStackTrace(); } } }
方法二:
package com.qiu.util; import java.io.*; import javax.swing.*; import java.awt.*; import java.awt.event.*; import java.awt.image.*; import javax.imageio.*; /** * 一个简单的屏幕抓图 * **/ public class ScreenCapture { // test main public static void main(String[] args) throws Exception { String userdir = System.getProperty("user.dir"); File tempFile = new File("d:", "temp.png"); ScreenCapture capture = ScreenCapture.getInstance(); capture.captureImage(); JFrame frame = new JFrame(); JPanel panel = new JPanel(); panel.setLayout(new BorderLayout()); JLabel imagebox = new JLabel(); panel.add(BorderLayout.CENTER, imagebox); imagebox.setIcon(capture.getPickedIcon()); capture.saveToFile(tempFile); capture.captureImage(); imagebox.setIcon(capture.getPickedIcon()); frame.setContentPane(panel); frame.setSize(400, 300); frame.show(); System.out.println("Over"); } private ScreenCapture() { try { robot = new Robot(); } catch (AWTException e) { System.err.println("Internal Error: " + e); e.printStackTrace(); } JPanel cp = (JPanel) dialog.getContentPane(); cp.setLayout(new BorderLayout()); labFullScreenImage.addMouseListener(new MouseAdapter() { public void mouseReleased(MouseEvent evn) { isFirstPoint = true; pickedImage = fullScreenImage.getSubimage(recX, recY, recW, recH); dialog.setVisible(false); } }); labFullScreenImage.addMouseMotionListener(new MouseMotionAdapter() { public void mouseDragged(MouseEvent evn) { if (isFirstPoint) { x1 = evn.getX(); y1 = evn.getY(); isFirstPoint = false; } else { x2 = evn.getX(); y2 = evn.getY(); int maxX = Math.max(x1, x2); int maxY = Math.max(y1, y2); int minX = Math.min(x1, x2); int minY = Math.min(y1, y2); recX = minX; recY = minY; recW = maxX - minX; recH = maxY - minY; labFullScreenImage.drawRectangle(recX, recY, recW, recH); } } public void mouseMoved(MouseEvent e) { labFullScreenImage.drawCross(e.getX(), e.getY()); } }); cp.add(BorderLayout.CENTER, labFullScreenImage); dialog.setCursor(Cursor.getPredefinedCursor(Cursor.CROSSHAIR_CURSOR)); dialog.setAlwaysOnTop(true); dialog.setMaximumSize(Toolkit.getDefaultToolkit().getScreenSize()); dialog.setUndecorated(true); dialog.setSize(dialog.getMaximumSize()); dialog.setModal(true); } // Singleton Pattern public static ScreenCapture getInstance() { return defaultCapturer; } /** 捕捉全屏慕 */ public Icon captureFullScreen() { fullScreenImage = robot.createScreenCapture(new Rectangle(Toolkit .getDefaultToolkit().getScreenSize())); ImageIcon icon = new ImageIcon(fullScreenImage); return icon; } /** 捕捉屏幕的一个矫形区域 */ public void captureImage() { fullScreenImage = robot.createScreenCapture(new Rectangle(Toolkit .getDefaultToolkit().getScreenSize())); ImageIcon icon = new ImageIcon(fullScreenImage); labFullScreenImage.setIcon(icon); dialog.setVisible(true); } /** 得到捕捉后的BufferedImage */ public BufferedImage getPickedImage() { return pickedImage; } /** 得到捕捉后的Icon */ public ImageIcon getPickedIcon() { return new ImageIcon(getPickedImage()); } /** * 储存为一个文件,为PNG格式 * * @deprecated replaced by saveAsPNG(File file) **/ @Deprecated public void saveToFile(File file) throws IOException { ImageIO.write(getPickedImage(), defaultImageFormater, file); } /** 储存为一个文件,为PNG格式 */ public void saveAsPNG(File file) throws IOException { ImageIO.write(getPickedImage(), "png", file); } /** 储存为一个JPEG格式图像文件 */ public void saveAsJPEG(File file) throws IOException { ImageIO.write(getPickedImage(), "JPEG", file); } /** 写入一个OutputStream */ public void write(OutputStream out) throws IOException { ImageIO.write(getPickedImage(), defaultImageFormater, out); } // singleton design pattern private static ScreenCapture defaultCapturer = new ScreenCapture(); private int x1, y1, x2, y2; private int recX, recY, recH, recW; // 截取的图像 private boolean isFirstPoint = true; private BackgroundImage labFullScreenImage = new BackgroundImage(); private Robot robot; private BufferedImage fullScreenImage; private BufferedImage pickedImage; private String defaultImageFormater = "png"; private JDialog dialog = new JDialog(); } /** 显示图片的Label */ class BackgroundImage extends JLabel { public void paintComponent(Graphics g) { super.paintComponent(g); g.drawRect(x, y, w, h); String area = Integer.toString(w) + " * " + Integer.toString(h); g.drawString(area, x + (int) w / 2 - 15, y + (int) h / 2); g.drawLine(lineX, 0, lineX, getHeight()); g.drawLine(0, lineY, getWidth(), lineY); } public void drawRectangle(int x, int y, int width, int height) { this.x = x; this.y = y; h = height; w = width; repaint(); } public void drawCross(int x, int y) { lineX = x; lineY = y; repaint(); } int lineX, lineY; int x, y, h, w; }
方法三:
因为有最小化到系统托盘,还是需要一张名为bg.gif作为托盘图标,图片应放在同级目录下,否则会空指针异常。
主要的截屏代码部分是:
Robot ro=new Robot(); Toolkit tk=Toolkit.getDefaultToolkit(); Dimension di=tk.getScreenSize(); Rectangle rec=new Rectangle(0,0,di.width,di.height); BufferedImage bi=ro.createScreenCapture(rec);
(源代码来源于CSDN)
import java.awt.*; import java.awt.datatransfer.DataFlavor; import java.awt.datatransfer.Transferable; import java.awt.datatransfer.UnsupportedFlavorException; import java.awt.event.*; import javax.swing.*; import java.io.*; import javax.imageio.*; import java.awt.image.*; public class CaptureScreen extends JFrame implements ActionListener{ private JButton start,cancel,saveAll; private JPanel c; private BufferedImage get; private JTabbedPane jtp;//一个放置很多份图片 private int index;//一个一直会递增的索引,用于标认图片 private JRadioButton java,system;//JAVA界面,系统界面 /** Creates a new instance of CaptureScreen */ public CaptureScreen() { super("屏幕截取软件(第三版)"); try{ UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName()); }catch(Exception exe){ exe.printStackTrace(); } initWindow(); initOther(); initTrayIcon(); } private void initOther(){ jtp=new JTabbedPane(JTabbedPane.TOP,JTabbedPane.SCROLL_TAB_LAYOUT); } private void initWindow(){ start=new JButton("开始截取"); saveAll=new JButton("保存所有"); cancel=new JButton("退出"); start.addActionListener(this); saveAll.addActionListener(this); cancel.addActionListener(this); JPanel buttonJP=new JPanel(); c=new JPanel(new BorderLayout()); c.setBackground(Color.BLACK); JLabel jl=new JLabel("屏幕截取",JLabel.CENTER); jl.setFont(new Font("黑体",Font.BOLD,40)); jl.setForeground(Color.RED); c.add(jl,BorderLayout.CENTER); buttonJP.add(start); buttonJP.add(saveAll); buttonJP.add(cancel); buttonJP.setBorder(BorderFactory.createTitledBorder("公共操作区")); JPanel jp=new JPanel();//放两个单选按钮的面板 jp.add(java=new JRadioButton("java界面")); jp.add(system=new JRadioButton("系统界面",true)); java.addActionListener(this); system.addActionListener(this); jp.setBorder(BorderFactory.createTitledBorder("界面风格")); ButtonGroup bg=new ButtonGroup(); bg.add(java); bg.add(system); JPanel all=new JPanel(); all.add(jp); all.add(buttonJP); this.getContentPane().add(c,BorderLayout.CENTER); this.getContentPane().add(all,BorderLayout.SOUTH); this.setSize(500,400); this.setLocationRelativeTo(null); this.setVisible(true); this.setAlwaysOnTop(true); this.setDefaultCloseOperation(JFrame.DO_NOTHING_ON_CLOSE); this.addWindowListener(new WindowAdapter(){ public void windowClosing(WindowEvent we){ CaptureScreen.this.setVisible(false); } }); } private void initTrayIcon(){ try{ SystemTray st=SystemTray.getSystemTray(); Image im=ImageIO.read(this.getClass().getResource("bg.gif")); PopupMenu pm=new PopupMenu("弹出菜单"); pm.add(new MenuItem("关于")).addActionListener(new ActionListener(){ public void actionPerformed(ActionEvent ae){ JOptionPane.showMessageDialog(CaptureScreen.this,"<html><Font color=red><center><h2>关于</h2></center></Font>" + "这是一款纯JAVA的屏幕截取程序<br>在以前的基础上增加了一些常用的功能,<br>" + "比如,批量保存,多幅截取,复制到系统粘帖板...<br>" + "在使用过程中有任何问题,欢迎联系.<br>" + "<Font size=5 color=blue>作者:千里冰封<br>" + "<i>QQ:24325142</i><br></Font></html>"); } }); pm.addSeparator(); pm.add(new MenuItem("显示主窗口")).addActionListener(new ActionListener(){ public void actionPerformed(ActionEvent ae){ CaptureScreen.this.setVisible(true); } }); pm.add(new MenuItem("开始截取")).addActionListener(new ActionListener(){ public void actionPerformed(ActionEvent ae){ doStart(); } }); pm.add(new MenuItem("退出程序")).addActionListener(new ActionListener(){ public void actionPerformed(ActionEvent ae){ System.exit(0); } }); TrayIcon ti=new TrayIcon(im,"JAVA屏幕截取",pm); st.add(ti); ti.addActionListener(new ActionListener(){ public void actionPerformed(ActionEvent ae){ CaptureScreen.this.setVisible(true); } }); }catch(Exception exe){ exe.printStackTrace(); } } private void updates(){ this.setVisible(true); if(get!=null){ //如果索引是0,则表示一张图片都没有被加入过, //则要清除当前的东西,重新把tabpane放进来 if(index==0){ c.removeAll(); c.add(jtp,BorderLayout.CENTER); }else{//否则的话,直接对tabpane添加面板就可以了 //就什么都不用做了 } PicPanel pic=new PicPanel(get); jtp.addTab("图片"+(++index),pic); jtp.setSelectedComponent(pic); SwingUtilities.updateComponentTreeUI(c); } } private void doStart(){ try{ this.setVisible(false); Thread.sleep(500);//睡500毫秒是为了让主窗完全不见 Robot ro=new Robot(); Toolkit tk=Toolkit.getDefaultToolkit(); Dimension di=tk.getScreenSize(); Rectangle rec=new Rectangle(0,0,di.width,di.height); BufferedImage bi=ro.createScreenCapture(rec); JFrame jf=new JFrame(); Temp temp=new Temp(jf,bi,di.width,di.height); jf.getContentPane().add(temp,BorderLayout.CENTER); jf.setUndecorated(true); jf.setSize(di); jf.setVisible(true); jf.setAlwaysOnTop(true); } catch(Exception exe){ exe.printStackTrace(); } } /** *公共方法,处理保存所有的图片 */ public void doSaveAll(){ if(jtp.getTabCount()==0){ JOptionPane.showMessageDialog(this,"图片不能为空!!","错误",JOptionPane.ERROR_MESSAGE); return; } JFileChooser jfc=new JFileChooser("."); jfc.addChoosableFileFilter(new GIFfilter()); jfc.addChoosableFileFilter(new BMPfilter()); jfc.addChoosableFileFilter(new JPGfilter()); jfc.addChoosableFileFilter(new PNGfilter()); int i=jfc.showSaveDialog(this); if(i==JFileChooser.APPROVE_OPTION){ File file=jfc.getSelectedFile(); String about="PNG"; String ext=file.toString().toLowerCase(); javax.swing.filechooser.FileFilter ff=jfc.getFileFilter(); if(ff instanceof JPGfilter){ about="JPG"; } else if(ff instanceof PNGfilter){ about="PNG"; }else if(ff instanceof BMPfilter){ about="BMP"; }else if(ff instanceof GIFfilter){ about="GIF"; } if(ext.endsWith(about.toLowerCase())){ ext=ext.substring(0,ext.lastIndexOf(about.toLowerCase())); } //起一个线程去保存这些图片并显示出进度条 new SaveAllThread(ext,about).setVisible(true); } } //专门用来保存所有图片的线程类,它还要显示出保存的进度条 private class SaveAllThread extends JDialog implements Runnable{ private String name;//文件名头部份 private String ext;//文件格式 private JProgressBar jpb;//一个进度条 private JLabel info;// 一个信息显示条 private int allTask,doneTask;//所有任务,已完成任务 public SaveAllThread(String name,String ext){ super(CaptureScreen.this,"保存",true); this.name=name; this.ext=ext; initWindow(); } private void initWindow(){ jpb=new JProgressBar(); allTask=jtp.getTabCount(); jpb.setMaximum(allTask); jpb.setMinimum(0); jpb.setValue(0); jpb.setStringPainted(true); setProgressBarString(); info=new JLabel("正在保存到:"); this.getContentPane().setBackground(Color.CYAN); this.add(info,BorderLayout.NORTH); this.add(jpb,BorderLayout.SOUTH); this.setUndecorated(true); this.setSize(300,100); this.setLocationRelativeTo(CaptureScreen.this); new Thread(this).start(); } private void setProgressBarString(){ jpb.setString(""+doneTask+"/"+allTask); } public void run(){ try{ for(int i=0;i<allTask;i++){ PicPanel pp=(PicPanel)jtp.getComponentAt(i); BufferedImage image=pp.getImage(); File f= new File(name+(doneTask+1)+"."+ext.toLowerCase()); info.setText("<html><b>正在保存到:</b><br>"+f.toString()+"</html>"); ImageIO.write(image,ext,f); doneTask++; jpb.setValue(doneTask); setProgressBarString(); Thread.sleep(500); } JOptionPane.showMessageDialog(this,"保存完毕!!"); this.dispose(); }catch(Exception exe){ exe.printStackTrace(); this.dispose(); } } } /** *公用的处理保存图片的方法 *这个方法不再私有了 */ public void doSave(BufferedImage get){ try{ if(get==null){ JOptionPane.showMessageDialog(this,"图片不能为空!!","错误",JOptionPane.ERROR_MESSAGE); return; } JFileChooser jfc=new JFileChooser("."); jfc.addChoosableFileFilter(new GIFfilter()); jfc.addChoosableFileFilter(new BMPfilter()); jfc.addChoosableFileFilter(new JPGfilter()); jfc.addChoosableFileFilter(new PNGfilter()); int i=jfc.showSaveDialog(this); if(i==JFileChooser.APPROVE_OPTION){ File file=jfc.getSelectedFile(); String about="PNG"; String ext=file.toString().toLowerCase(); javax.swing.filechooser.FileFilter ff=jfc.getFileFilter(); if(ff instanceof JPGfilter){ about="JPG"; if(!ext.endsWith(".jpg")){ String ns=ext+".jpg"; file=new File(ns); } } else if(ff instanceof PNGfilter){ about="PNG"; if(!ext.endsWith(".png")){ String ns=ext+".png"; file=new File(ns); } }else if(ff instanceof BMPfilter){ about="BMP"; if(!ext.endsWith(".bmp")){ String ns=ext+".bmp"; file=new File(ns); } }else if(ff instanceof GIFfilter){ about="GIF"; if(!ext.endsWith(".gif")){ String ns=ext+".gif"; file=new File(ns); } } if(ImageIO.write(get,about,file)){ JOptionPane.showMessageDialog(this,"保存成功!"); } else JOptionPane.showMessageDialog(this,"保存失败!"); } } catch(Exception exe){ exe.printStackTrace(); } } /** *公共的处理把当前的图片加入剪帖板的方法 */ public void doCopy(final BufferedImage image){ try{ if(get==null){ JOptionPane.showMessageDialog(this,"图片不能为空!!","错误",JOptionPane.ERROR_MESSAGE); return; } Transferable trans = new Transferable(){ public DataFlavor[] getTransferDataFlavors() { return new DataFlavor[] { DataFlavor.imageFlavor }; } public boolean isDataFlavorSupported(DataFlavor flavor) { return DataFlavor.imageFlavor.equals(flavor); } public Object getTransferData(DataFlavor flavor) throws UnsupportedFlavorException, IOException { if(isDataFlavorSupported(flavor)) return image; throw new UnsupportedFlavorException(flavor); } }; Toolkit.getDefaultToolkit().getSystemClipboard().setContents(trans, null); JOptionPane.showMessageDialog(this,"已复制到系统粘帖板!!"); }catch(Exception exe){ exe.printStackTrace(); JOptionPane.showMessageDialog(this,"复制到系统粘帖板出错!!","错误",JOptionPane.ERROR_MESSAGE); } } //处理关闭事件 private void doClose(Component c){ jtp.remove(c); c=null; System.gc(); } public void actionPerformed(ActionEvent ae){ Object source=ae.getSource(); if(source==start){ doStart(); } else if(source==cancel){ System.exit(0); }else if(source==java){ try{ UIManager.setLookAndFeel(UIManager.getCrossPlatformLookAndFeelClassName()); SwingUtilities.updateComponentTreeUI(this); }catch(Exception exe){ exe.printStackTrace(); } }else if(source==system){ try{ UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName()); SwingUtilities.updateComponentTreeUI(this); }catch(Exception exe){ exe.printStackTrace(); } }else if(source==saveAll){ doSaveAll(); } } //一个内部类,它表示一个面板,一个可以被放进tabpane的面板 //也有自己的一套处理保存和复制的方法 private class PicPanel extends JPanel implements ActionListener{ JButton save,copy,close;//表示保存,复制,关闭的按钮 BufferedImage get;//得到的图片 public PicPanel(BufferedImage get){ super(new BorderLayout()); this.get=get; initPanel(); } public BufferedImage getImage(){ return get; } private void initPanel(){ save=new JButton("保存(S)"); copy=new JButton("复制到剪帖板(C)"); close=new JButton("关闭(X)"); save.setMnemonic('S'); copy.setMnemonic('C'); close.setMnemonic('X'); JPanel buttonPanel=new JPanel(); buttonPanel.add(copy); buttonPanel.add(save); buttonPanel.add(close); JLabel icon=new JLabel(new ImageIcon(get)); this.add(new JScrollPane(icon),BorderLayout.CENTER); this.add(buttonPanel,BorderLayout.SOUTH); save.addActionListener(this); copy.addActionListener(this); close.addActionListener(this); } public void actionPerformed(ActionEvent e) { Object source=e.getSource(); if(source==save){ doSave(get); }else if(source==copy){ doCopy(get); }else if(source==close){ get=null; doClose(this); } } } //保存BMP格式的过滤器 private class BMPfilter extends javax.swing.filechooser.FileFilter{ public BMPfilter(){ } public boolean accept(File file){ if(file.toString().toLowerCase().endsWith(".bmp")|| file.isDirectory()){ return true; } else return false; } public String getDescription(){ return "*.BMP(BMP图像)"; } } //保存JPG格式的过滤器 private class JPGfilter extends javax.swing.filechooser.FileFilter{ public JPGfilter(){ } public boolean accept(File file){ if(file.toString().toLowerCase().endsWith(".jpg")|| file.isDirectory()){ return true; } else return false; } public String getDescription(){ return "*.JPG(JPG图像)"; } } //保存GIF格式的过滤器 private class GIFfilter extends javax.swing.filechooser.FileFilter{ public GIFfilter(){ } public boolean accept(File file){ if(file.toString().toLowerCase().endsWith(".gif")|| file.isDirectory()){ return true; } else return false; } public String getDescription(){ return "*.GIF(GIF图像)"; } } //保存PNG格式的过滤器 private class PNGfilter extends javax.swing.filechooser.FileFilter{ public boolean accept(File file){ if(file.toString().toLowerCase().endsWith(".png")|| file.isDirectory()){ return true; } else return false; } public String getDescription(){ return "*.PNG(PNG图像)"; } } //一个暂时类,用于显示当前的屏幕图像 private class Temp extends JPanel implements MouseListener,MouseMotionListener{ private BufferedImage bi; private int width,height; private int startX,startY,endX,endY,tempX,tempY; private JFrame jf; private Rectangle select=new Rectangle(0,0,0,0);//表示选中的区域 private Cursor cs=new Cursor(Cursor.CROSSHAIR_CURSOR);//表示一般情况下的鼠标状态 private States current=States.DEFAULT;// 表示当前的编辑状态 private Rectangle[] rec;//表示八个编辑点的区域 //下面四个常量,分别表示谁是被选中的那条线上的端点 public static final int START_X=1; public static final int START_Y=2; public static final int END_X=3; public static final int END_Y=4; private int currentX,currentY;//当前被选中的X和Y,只有这两个需要改变 private Point p=new Point();//当前鼠标移的地点 private boolean showTip=true;//是否显示提示.如果鼠标左键一按,则提示不再显了 public Temp(JFrame jf,BufferedImage bi,int width,int height){ this.jf=jf; this.bi=bi; this.width=width; this.height=height; this.addMouseListener(this); this.addMouseMotionListener(this); initRecs(); } private void initRecs(){ rec=new Rectangle[8]; for(int i=0;i<rec.length;i++){ rec[i]=new Rectangle(); } } public void paintComponent(Graphics g){ g.drawImage(bi,0,0,width,height,this); g.setColor(Color.RED); g.drawLine(startX,startY,endX,startY); g.drawLine(startX,endY,endX,endY); g.drawLine(startX,startY,startX,endY); g.drawLine(endX,startY,endX,endY); int x=startX<endX?startX:endX; int y=startY<endY?startY:endY; select=new Rectangle(x,y,Math.abs(endX-startX),Math.abs(endY-startY)); int x1=(startX+endX)/2; int y1=(startY+endY)/2; g.fillRect(x1-2,startY-2,5,5); g.fillRect(x1-2,endY-2,5,5); g.fillRect(startX-2,y1-2,5,5); g.fillRect(endX-2,y1-2,5,5); g.fillRect(startX-2,startY-2,5,5); g.fillRect(startX-2,endY-2,5,5); g.fillRect(endX-2,startY-2,5,5); g.fillRect(endX-2,endY-2,5,5); rec[0]=new Rectangle(x-5,y-5,10,10); rec[1]=new Rectangle(x1-5,y-5,10,10); rec[2]=new Rectangle((startX>endX?startX:endX)-5,y-5,10,10); rec[3]=new Rectangle((startX>endX?startX:endX)-5,y1-5,10,10); rec[4]=new Rectangle((startX>endX?startX:endX)-5,(startY>endY?startY:endY)-5,10,10); rec[5]=new Rectangle(x1-5,(startY>endY?startY:endY)-5,10,10); rec[6]=new Rectangle(x-5,(startY>endY?startY:endY)-5,10,10); rec[7]=new Rectangle(x-5,y1-5,10,10); if(showTip){ g.setColor(Color.CYAN); g.fillRect(p.x,p.y,170,20); g.setColor(Color.RED); g.drawRect(p.x,p.y,170,20); g.setColor(Color.BLACK); g.drawString("请按住鼠标左键不放选择截图区",p.x,p.y+15); } } //根据东南西北等八个方向决定选中的要修改的X和Y的座标 private void initSelect(States state){ switch(state){ case DEFAULT: currentX=0; currentY=0; break; case EAST: currentX=(endX>startX?END_X:START_X); currentY=0; break; case WEST: currentX=(endX>startX?START_X:END_X); currentY=0; break; case NORTH: currentX=0; currentY=(startY>endY?END_Y:START_Y); break; case SOUTH: currentX=0; currentY=(startY>endY?START_Y:END_Y); break; case NORTH_EAST: currentY=(startY>endY?END_Y:START_Y); currentX=(endX>startX?END_X:START_X); break; case NORTH_WEST: currentY=(startY>endY?END_Y:START_Y); currentX=(endX>startX?START_X:END_X); break; case SOUTH_EAST: currentY=(startY>endY?START_Y:END_Y); currentX=(endX>startX?END_X:START_X); break; case SOUTH_WEST: currentY=(startY>endY?START_Y:END_Y); currentX=(endX>startX?START_X:END_X); break; default: currentX=0; currentY=0; break; } } public void mouseMoved(MouseEvent me){ doMouseMoved(me); initSelect(current); if(showTip){ p=me.getPoint(); repaint(); } } //特意定义一个方法处理鼠标移动,是为了每次都能初始化一下所要选择的地区 private void doMouseMoved(MouseEvent me){ if(select.contains(me.getPoint())){ this.setCursor(new Cursor(Cursor.MOVE_CURSOR)); current=States.MOVE; } else{ States[] st=States.values(); for(int i=0;i<rec.length;i++){ if(rec[i].contains(me.getPoint())){ current=st[i]; this.setCursor(st[i].getCursor()); return; } } this.setCursor(cs); current=States.DEFAULT; } } public void mouseExited(MouseEvent me){ } public void mouseEntered(MouseEvent me){ } public void mouseDragged(MouseEvent me){ int x=me.getX(); int y=me.getY(); if(current==States.MOVE){ startX+=(x-tempX); startY+=(y-tempY); endX+=(x-tempX); endY+=(y-tempY); tempX=x; tempY=y; }else if(current==States.EAST||current==States.WEST){ if(currentX==START_X){ startX+=(x-tempX); tempX=x; }else{ endX+=(x-tempX); tempX=x; } }else if(current==States.NORTH||current==States.SOUTH){ if(currentY==START_Y){ startY+=(y-tempY); tempY=y; }else{ endY+=(y-tempY); tempY=y; } }else if(current==States.NORTH_EAST||current==States.NORTH_EAST|| current==States.SOUTH_EAST||current==States.SOUTH_WEST){ if(currentY==START_Y){ startY+=(y-tempY); tempY=y; }else{ endY+=(y-tempY); tempY=y; } if(currentX==START_X){ startX+=(x-tempX); tempX=x; }else{ endX+=(x-tempX); tempX=x; } }else{ startX=tempX; startY=tempY; endX=me.getX(); endY=me.getY(); } this.repaint(); } public void mousePressed(MouseEvent me){ showTip=false; tempX=me.getX(); tempY=me.getY(); } public void mouseReleased(MouseEvent me){ if(me.isPopupTrigger()){ if(current==States.MOVE){ showTip=true; p=me.getPoint(); startX=0; startY=0; endX=0; endY=0; repaint(); } else{ jf.dispose(); updates(); } } } public void mouseClicked(MouseEvent me){ if(me.getClickCount()==2){ //Rectangle rec=new Rectangle(startX,startY,Math.abs(endX-startX),Math.abs(endY-startY)); Point p=me.getPoint(); if(select.contains(p)){ if(select.x+select.width<this.getWidth()&&select.y+select.height<this.getHeight()){ get=bi.getSubimage(select.x,select.y,select.width,select.height); jf.dispose(); updates(); }else{ int wid=select.width,het=select.height; if(select.x+select.width>=this.getWidth()){ wid=this.getWidth()-select.x; } if(select.y+select.height>=this.getHeight()){ het=this.getHeight()-select.y; } get=bi.getSubimage(select.x,select.y,wid,het); jf.dispose(); updates(); } } } } } public static void main(String args[]){ SwingUtilities.invokeLater(new Runnable(){ public void run(){ new CaptureScreen(); } }); } } //一些表示状态的枚举 enum States{ NORTH_WEST(new Cursor(Cursor.NW_RESIZE_CURSOR)),//表示西北角 NORTH(new Cursor(Cursor.N_RESIZE_CURSOR)), NORTH_EAST(new Cursor(Cursor.NE_RESIZE_CURSOR)), EAST(new Cursor(Cursor.E_RESIZE_CURSOR)), SOUTH_EAST(new Cursor(Cursor.SE_RESIZE_CURSOR)), SOUTH(new Cursor(Cursor.S_RESIZE_CURSOR)), SOUTH_WEST(new Cursor(Cursor.SW_RESIZE_CURSOR)), WEST(new Cursor(Cursor.W_RESIZE_CURSOR)), MOVE(new Cursor(Cursor.MOVE_CURSOR)), DEFAULT(new Cursor(Cursor.DEFAULT_CURSOR)); private Cursor cs; States(Cursor cs){ this.cs=cs; } public Cursor getCursor(){ return cs; } }
希望本文所述对大家Java程序设计有所帮助。