paintpanel.java

用java编写的画图面板程序（有源代码）

/**
 * @(#)PaintPanel.java
 */
package project.paint;

import java.awt.*;
import java.awt.event.*;
import java.awt.image.BufferedImage;
import java.awt.image.RenderedImage;

import javax.imageio.ImageIO;
import javax.swing.*;
import java.io.*;
import java.util.*;

public class PaintPanel extends JPanel {

	public static final int GETCOLOR = 99;

	public Project instance;

	private static final int OBJECTCOUNT = 65536;
	PopMenu popMenu;
	JPanel c;
	Color backColor;
	int width = 400;
	int height = 300;
	int changeSize;
	File fileName;

	Color nowColor;

	Color forColor;
	Color bacColor;
	Color midColor;

	Point p1;
	Point p2;
	boolean isFill;
	float stroke;
	int nowType;
	LinkedList<BaseObject> graphics;
	LinkedList<BaseObject> undoGraphics;

	boolean isDrawing;
	boolean isChanging;
	boolean isFilling;
	boolean isRotating;
	boolean isSquare; // 是否正二维图形
	int gradientPaint; // 渐变涂色样式
	int nowObject; // 保存选中物体
	int nowChangeGraphics;
	int nowRotate;
	int nowGraphics;
	int xOffset, yOffset;
	int preX;

	/**
	 * 构造出绘制区域
	 * 
	 * @param o
	 *            画图板的实例对象
	 */
	public PaintPanel(Project o) {
		if (o == null)
			return;
		instance = o;

		setLayout(null);
		// 初始化参数
		initParam();

		c = new JPanel() {
			public void paint(Graphics g) {
				// super.paint(g);

				if (nowType == BaseObject.PENCIL && isDrawing) { // 如果是铅笔的话
					((BaseObject) (graphics.getLast()))
							.drawLastLine((Graphics2D) g);
					// graphics.get(graphics.size()-1)
				} else {
					Image buffer = createImage(width, height);
					Graphics2D gg = (Graphics2D) (buffer.getGraphics());
					// Graphics2D gg=(Graphics2D)g;

					gg.setColor(backColor);
					gg.fillRect(0, 0, width, height);
					for (int j = 0; j < graphics.size(); j++) {
						draw(gg, (BaseObject) (graphics.get(j)));
					}
					if (nowGraphics >= 0) {
						nowObject = nowGraphics;
						drawFocus(gg, nowGraphics);
						setDelable(true);
					} else if (nowChangeGraphics >= 0) {
						drawFocus(gg, nowChangeGraphics);
					} else if (nowRotate >= 0) {
						BaseObject gh = (BaseObject) (graphics.get(nowRotate));
						gh.drawRotateFocus(gg);
					} else {
						nowObject = -1;
						setDelable(false);
					}
					g.drawImage(buffer, 0, 0, this);
				}
			}

			void draw(Graphics2D g2d, BaseObject g) {
				g.draw(g2d);
			}

			private void drawFocus(Graphics2D gg, int index) {
				if (nowType == -1) {
					try {
						BaseObject gh = (BaseObject) (graphics.get(index));
						gg.setColor(Color.BLACK);
						gh.drawMoveFocus(gg, Color.WHITE);
					} catch (Exception e) { // 可能产生Exception，比如操作太快，
						// 不知道为什么会产生NullPointerException
						System.out.println("==============================");
						System.out.println("drawFocus(Graphics2D,int)方法出现异常:");
					}
				}
			}
		};
		c.setFocusable(true);
		c.setBackground(backColor);
		c.setBounds(6, 6, width, height);
		c.addMouseListener(new MouseAdapter() {
			public void mouseClicked(MouseEvent e) {
				c_mouseClicked(e);
			}

			public void mousePressed(MouseEvent e) {
				c_mousePressed(e);
			}

			public void mouseReleased(MouseEvent e) {
				c_mouseReleased(e);
			}

			public void mouseExited(MouseEvent e) {
				c_mouseExited(e);
			}
		});
		c.addMouseMotionListener(new MouseMotionAdapter() {
			public void mouseDragged(MouseEvent e) {
				c_mouseDragged(e);
			}

			public void mouseMoved(MouseEvent e) {
				c_mouseMoved(e);
			}
		});
		c.addKeyListener(new KeyAdapter() {
			public void keyTyped(KeyEvent e) {
				c_keyTyped(e);
			}
		});
		// c.setCursor(new Cursor(Cursor.CROSSHAIR_CURSOR));
		popMenu = new PopMenu(this);
		c.add(popMenu);

		add(c);
		addMouseMotionListener(new MouseMotionAdapter() {
			public void mouseDragged(MouseEvent e) {
				p_mouseDragged(e);
			}

			public void mouseMoved(MouseEvent e) {
				p_mouseMoved(e);
			}
		});
		addMouseListener(new MouseAdapter() {
			public void mousePressed(MouseEvent e) {
				p_mousePressed(e);
			}

			public void mouseReleased(MouseEvent e) {
				p_mouseReleased(e);
			}
		});
		setBackground(Color.DARK_GRAY);
		setType(-1);
	}

	public void paint(Graphics g) {
		super.paint(g);
		g.setColor(new Color(255, 255, 255));
		g.drawRect(1, 1, 3, 3);
		g.drawRect(width / 2, 1, 3, 3);
		g.drawRect(width + 5, 1, 3, 3);
		g.drawRect(1, height + 5, 3, 3);
		g.drawRect(1, height / 2, 3, 3);

		g.fillRect(width + 6, height / 2, 4, 4);
		g.fillRect(width + 6, height + 6, 4, 4);
		g.fillRect(width / 2, height + 6, 4, 4);

		// redraw();
	}

	public void c_mouseClicked(MouseEvent e) {
		if (e.getButton() == e.BUTTON3) {
			if (nowObject >= 0) {
				popMenu.show(this, e.getX(), e.getY());
			}
		} else if (e.getModifiersEx() == e.CTRL_DOWN_MASK) {
			/*
			 * BaseObject gh=new ObjPolygon((int)(Math.random()9+3)); int
			 * size=(int)(Math.random()50+50); graphics.add(gh); int
			 * iR=(int)(Math.random()255); int iG=(int)(Math.random()255); int
			 * iB=(int)(Math.random()255); gh.color=new Color(iR,iG,iB);
			 * gh.color2=new Color(iB,iG,iR); gh.gradientPaint=3;
			 * gh.stroke=stroke;
			 * 
			 * gh.addPoint(e.getX(),e.getY());
			 * gh.changeSize(e.getX()+size,e.getY()+size); if
			 * ((Math.random()10)>=5) gh.filled=true; else gh.filled=false; /
			 * 
			 * redraw();
			 * 
			 * instance.setState("创建了一个彩蛋~~ ^_^  Copyright 2008 (c) 黑色珊瑚");
			 */
		}
	}

	public void c_mousePressed(MouseEvent e) {
		if (isFilling && nowGraphics >= 0) {
			if (gradientPaint == 4) {
				if (p1 == null) {
					p1 = new Point();
					p2 = new Point();
				}
				p1.x = e.getX();
				p1.y = e.getY();
				return;
			}
			BaseObject gh = (BaseObject) (graphics.get(nowGraphics));
			gh.color = forColor;
			gh.color2 = bacColor;
			gh.gradientPaint = gradientPaint;
			if (gradientPaint > 0) {
				if (gh.p1 == null) {
					gh.p1 = new Point(gh.X.get(0), gh.Y.get(0));
					gh.p2 = new Point(gh.X.get(0), gh.Y.get(0));
				} else {
					gh.p1.x = gh.X.get(0);
					gh.p1.y = gh.Y.get(0);
					gh.p2.x = gh.X.get(0);
					gh.p2.y = gh.Y.get(0);
				}
				if (gh.X.size() == 2) {
					int xB = gh.X.get(0);
					int yB = gh.Y.get(0);
					if (gradientPaint == 1) {
						gh.p2.x += gh.X.get(1) - xB;
					} else if (gradientPaint == 2) {
						gh.p2.y += gh.Y.get(1) - yB;
					} else if (gradientPaint == 3) {
						gh.p2.x += gh.X.get(1) - xB;
						gh.p2.y += gh.Y.get(1) - yB;
					}
				}
				gh.setGradientPaint(gh.p1, gh.p2);
			}
			gh.fill();
			redraw();
		} else if (nowType == -1 || nowType == BaseObject.FILL
				|| nowType == BaseObject.ROTATE) {
			redraw();
			if (nowChangeGraphics >= 0) {
				isChanging = true;
				BaseObject gh = (BaseObject) (graphics.get(nowChangeGraphics));
				xOffset = e.getX() - gh.getPointX(1); // gh.getMaxX();
				// //graphics
				// [nowChangeGraphics
				// ].getPointX(1);
				yOffset = e.getY() - gh.getPointY(1);
			} else if (nowGraphics >= 0) {
				BaseObject gh = (BaseObject) (graphics.get(nowGraphics));
				xOffset = e.getX() - gh.getMinX();
				yOffset = e.getY() - gh.getMinY();
				instance.setState("选中物体 " + String.valueOf(nowGraphics) + " : "
						+ gh.toString());
			}
		} else {
			if (e.getButton() == e.BUTTON1) { // 左键
				if ((e.getModifiersEx() & e.CTRL_DOWN_MASK) == e.CTRL_DOWN_MASK) { // 按Ctrl键了
					nowColor = midColor;
				} else {
					nowColor = forColor;
				}
			} else if (e.getButton() == e.BUTTON3) { // 右键
				nowColor = bacColor;
			}
			BaseObject gh = createObject(e.getX(), e.getY());
			isDrawing = true;
			instance.setState("创建物体 " + String.valueOf(graphics.size() - 1)
					+ " : " + gh.toString());
		}
	}

	public void c_mouseReleased(MouseEvent e) {
		if (isFilling && nowGraphics >= 0 && gradientPaint == 4) {
			BaseObject gh = (BaseObject) (graphics.get(nowGraphics));
			p2.x = e.getX();
			p2.y = e.getY();
			gh.color = forColor;
			gh.color2 = bacColor;
			gh.gradientPaint = gradientPaint;
			gh.setGradientPaint(p1, p2);
			gh.fill();
			redraw();
		} else if (isDrawing) {
			isDrawing = false;
			BaseObject gh = (BaseObject) (graphics.getLast());
			if (e.getX() == gh.getPointX(0) && e.getY() == gh.getPointY(0)) {
				graphics.removeLast(); // graphics.remove(counts);
				return;
			}
			instance.setState("一共创建了 " + String.valueOf(graphics.size())
					+ " 个物体");
		} else if (isChanging) {
			isChanging = false;
			c_mouseMoved(e);
		}

		redraw();
	}

	public void c_mouseExited(MouseEvent e) {
		if (nowGraphics < 0 && nowChangeGraphics < 0 && nowObject < 0) {
			instance.setState("准备就绪");
		}
	}

	public void c_mouseDragged(MouseEvent e) {
		if (nowType == -1 || nowType == BaseObject.ROTATE) {
			int x = e.getX();
			int y = e.getY();
			if ((e.getModifiers() & e.BUTTON1_MASK) == e.BUTTON1_MASK) { // 左键
				if (nowChangeGraphics >= 0) {
					BaseObject gh = (BaseObject) (graphics
							.get(nowChangeGraphics));
					gh.changeSize(x - xOffset, y - yOffset);
					int x1 = gh.getPointX(0);
					int y1 = gh.getPointY(0);
					if ((x >= x1 && y >= y1) || (x <= x1 && y <= y1)) {
						c.setCursor(new Cursor(Cursor.NW_RESIZE_CURSOR));
					} else if ((x > x1 && y < y1) || (x < x1 && y > y1)) {
						c.setCursor(new Cursor(Cursor.NE_RESIZE_CURSOR));
					}

					instance.setState("正在改变大小 物体 "
							+ String.valueOf(nowChangeGraphics) + " : "
							+ String.valueOf(gh.getWidth()) + " * "
							+ String.valueOf(gh.getHeight()));
				} else if (nowGraphics >= 0) {
					BaseObject gh = (BaseObject) (graphics.get(nowGraphics));
					int iBuffX = x - xOffset - gh.getMinX(); // .getPointX(0);
					int iBuffY = y - yOffset - gh.getMinY();
					gh.moveObject(iBuffX, iBuffY);
					instance.setState("正在移动物体 " + String.valueOf(nowGraphics)
							+ " : " + gh.toString());
				} else if (nowRotate >= 0) {
					BaseObject gh = (BaseObject) (graphics.get(nowRotate));
					if (preX - e.getX() > 0)
						gh.rotateNum += 1 * Math.PI / 180;