Java实现简单的绘图软件

项目效果图：

项目源代码：

import java.awt.*;

import java.awt.event.*;

import java.awt.geom.Ellipse2D;

import java.awt.geom.Line2D;

import java.awt.geom.Rectangle2D;

import java.awt.image.BufferedImage;

import java.io.File;

import java.io.IOException;

import javax.imageio.ImageIO;

import javax.swing.*;

import javax.swing.filechooser.FileNameExtensionFilter;

/* author: 蒋冰*/

public class ImageDraw {

private int typeFlag = 1;

private int endFlag = 1;

private int strokeTemp = 1;

private Color color = Color.black;

private BasicStroke stroke = new BasicStroke();

private float pre_x = 0;

private float pre_y = 0;

private float start_x = 0;

private float start_y = 0;

private float start_X = 0;

private float start_Y = 0;

private float end_x = 0;

private float end_y = 0;

private float width = 0;

private float height = 0;

private final int AREA_WIDTH = 700;

private final int AREA_HEIGHT = 400;

private Line2D.Float line;

private Rectangle2D.Float rect;

private Ellipse2D.Float ellipse;

private File imageFile;

BufferedImage image = new BufferedImage(AREA_WIDTH , AREA_HEIGHT , BufferedImage.TYPE_INT_RGB);

Graphics2D g2 = (Graphics2D) image.getGraphics();

private JFrame frame = new JFrame("简单手绘程序");

private DrawPanel drawArea = new DrawPanel();

JButton buttonShowColor = new JButton("");

public void init(){

g2.fillRect(0 , 0 ,AREA_WIDTH , AREA_HEIGHT);

g2.setColor(Color.black);

drawArea.setPreferredSize(new Dimension(AREA_WIDTH , AREA_HEIGHT));

drawArea.addMouseMotionListener(new MouseMotionAdapter()

{

public void mouseDragged(MouseEvent e)

{

do_mouseDragged(e);

}

});

drawArea.addMouseListener(new MouseAdapter()

{

public void mousePressed(MouseEvent e1){

do_mousePressed(e1);

}

public void mouseReleased(MouseEvent e)

{

g2.setColor(color);

g2.setStroke(stroke);

endFlag = typeFlag;

drawArea.repaint();

}

public void mouseEntered(MouseEvent e){

frame.setCursor(new Cursor(Cursor.CROSSHAIR_CURSOR));

}

public void mouseExited(MouseEvent e){

frame.setCursor(null);

}

});

frame.add(drawArea);

JMenuBar mb = new JMenuBar();

JMenu menuFile = new JMenu("文件");

JMenuItem menuItemSave = new JMenuItem("保存"); menuItemSave.addActionListener(new ActionListener(){

public void actionPerformed(ActionEvent arg0) {

do_save_actionPerformed(arg0);

}

});

JMenuItem menuItemOpen = new JMenuItem("打开"); menuItemOpen.addActionListener(new ActionListener(){

public void actionPerformed(ActionEvent arg0) {

try {

do_open_actionPerformed(arg0);

} catch (IOException e) {

// TODO 自动生成的catch 块

e.printStackTrace();

}

}

});

JMenuItem menuItemExit = new JMenuItem("退出"); menuItemExit.addActionListener(new ActionListener(){

public void actionPerformed(ActionEvent arg0) {

System.exit(0);

}

});

menuFile.add(menuItemSave);

menuFile.add(menuItemOpen);

menuFile.add(menuItemExit);

mb.add(menuFile);

JPanel buttonPanel = new JPanel();

FlowLayout layout = new FlowLayout(FlowLayout.CENTER, 20, 20); buttonPanel.setLayout(layout);

buttonPanel.setBackground(Color.gray);

JButton buttonDraw = new JButton("绘图");

buttonDraw.addActionListener(new ActionListener(){

public void actionPerformed(ActionEvent arg0) {

typeFlag = 1;

}

});

buttonPanel.add(buttonDraw);

JButton buttonLine = new JButton("直线");

buttonLine.addActionListener(new ActionListener(){

public void actionPerformed(ActionEvent arg0) {

typeFlag = 2;

}

});

buttonPanel.add(buttonLine);

JButton buttonRect = new JButton("矩形");

buttonRect.addActionListener(new ActionListener(){

public void actionPerformed(ActionEvent arg0) {

typeFlag = 3;

}

});

buttonPanel.add(buttonRect);

JButton buttonEllipse = new JButton("椭圆");

buttonEllipse.addActionListener(new ActionListener(){

public void actionPerformed(ActionEvent arg0) {

typeFlag = 4;

}

});

buttonPanel.add(buttonEllipse);

JButton buttonDrop = new JButton("清除");

buttonDrop.addActionListener(new ActionListener(){

public void actionPerformed(ActionEvent arg0) {

typeFlag = 5;

g2.setColor(Color.white);

g2.fillRect(0 , 0 ,AREA_WIDTH , AREA_HEIGHT);

drawArea.repaint();

}

});

buttonPanel.add(buttonDrop);

JButton buttonColorChoose = new JButton("选择颜色"); buttonColorChoose.addActionListener(new ActionListener(){ public void actionPerformed(ActionEvent arg0) {

do_buttonColorChoose_actionPerformed(arg0);

}

});

buttonPanel.add(buttonColorChoose);

buttonShowColor = new JButton("");

buttonPanel.add(buttonShowColor);

JLabel label = new JLabel("边框：");

buttonPanel.add(label);

JComboBox combox = new JComboBox();

for(int i=1; i<=36; i++){

combox.addItem(i);

}

combox.addItemListener(new ItemListener() {

public void itemStateChanged(ItemEvent e) {

strokeTemp = Integer.parseInt(e.getItem().toString()) ;

stroke = new BasicStroke(strokeTemp);

}

});

buttonPanel.add(combox);

frame.add(buttonPanel,BorderLayout.SOUTH);

frame.add(mb,BorderLayout.NORTH);

frame.setBackground(Color.gray);

frame.pack();

frame.setVisible(true);

}

public static void main(String[] args)

{

new ImageDraw().init();

}

class DrawPanel extends JPanel

{

public void paint(Graphics g)

{

Graphics2D g2 = (Graphics2D) g;

g2.clearRect(0, 0, AREA_WIDTH, AREA_HEIGHT);

g2.setColor(color);

g2.setStroke(stroke);

g2.drawImage(image , 0 , 0 , null);

if(typeFlag == 2){

line = new Line2D.Float(start_x, start_y, end_x, end_y);

g2.draw(line);

}

if(typeFlag == 3){

rect = new Rectangle2D.Float(start_X, start_Y, width, height);

g2.draw(rect);

}

if(typeFlag == 4){

ellipse = new Ellipse2D.Float(start_X, start_Y, width, height);

g2.draw(ellipse);

}

if(typeFlag == 5){

g2.setColor(Color.white);

g2.fillRect(0 , 0 ,AREA_WIDTH , AREA_HEIGHT);

}

}

}

private void do_save_actionPerformed(ActionEvent arg0) {

// TODO 自动生成的方法存根

JFileChooser chooser = new JFileChooser();

chooser.setSelectedFile(new File(imageFile.getName()));

int option = chooser.showSaveDialog(null);

if(option == JFileChooser.APPROVE_OPTION){

File file = chooser.getSelectedFile();

try {

ImageIO.write(image, "jpg", file);

} catch (IOException e) {

// TODO 自动生成的catch 块

e.printStackTrace();

}

}

}

private void do_open_actionPerformed(ActionEvent arg0) throws IOException { // TODO 自动生成的方法存根

JFileChooser chooser = new JFileChooser();

chooser.setFileFilter(new FileNameExtensionFilter("图片文件","jpg","jpeg","jif"));

chooser.setFileSelectionMode(JFileChooser.FILES_ONLY);

int option = chooser.showOpenDialog(null);

if(option == JFileChooser.APPROVE_OPTION){

imageFile = chooser.getSelectedFile();

Image sourceImage = ImageIO.read(imageFile);

g2.drawImage(sourceImage, 0, 0, sourceImage.getWidth(null), sourceImage.getHeight(null), null);

drawArea.repaint();

}

}

private void do_buttonColorChoose_actionPerformed(ActionEvent arg0) {

// TODO 自动生成的方法存根

JColorChooser chooser = new JColorChooser();

color = chooser.showDialog(null, "请选取颜色", Color.black);

buttonShowColor.setBackground(color);

}

private void do_mouseDragged(MouseEvent e) {

end_x = e.getX();

end_y = e.getY();

width = Math.abs( end_x - start_x );

height = Math.abs( end_y - start_y );

if(end_x <= start_x && end_y <= start_y){

start_X = start_x - width;

start_Y = start_y - height;

}

if(end_x > start_x && end_y < start_y){

start_Y = start_y - height;

start_X = start_x;

}

if(end_x <= start_x && end_y >= start_y){

start_Y = start_y;

start_X = start_x - width;

}

if(end_x >= start_x && end_y >=start_y){

start_Y = start_y;

start_X = start_x;

}

if(typeFlag == 1){

if (pre_x > 0 && pre_y > 0)

{

line = new Line2D.Float(pre_x, pre_y, end_x, end_y);

g2.setColor(color);

g2.setStroke(stroke);

g2.draw(line);

}

pre_x = e.getX();

pre_y = e.getY();

drawArea.repaint();

}else{

drawArea.repaint();

}

}

private void do_mousePressed(MouseEvent e1) {

// TODO 自动生成的方法存根

width = 0;

height = 0;

start_x = end_x = pre_x = e1.getX();

start_y = end_y = pre_y = e1.getY();

if(endFlag == 2){

g2.draw(line);

}

if(endFlag == 3){

g2.draw(rect);

}

if(endFlag == 4)

{

g2.draw(ellipse);

}

drawArea.repaint();

}

}