一个简单的画图板程序。
用到的图片在附件中。（新手，多包涵）
package netjava0626;
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.MouseListener;
import java.awt.event.MouseMotionAdapter;
import java.awt.event.MouseMotionListener;
//定义一个画板类
public class DrawingBoard {
private String biaozhi = "huabi";
private String color;
private Graphics g;
private int x1, y1, x2, y2, x3, y3, w, h;
private JLabel lab;
// 初始化面板并实现组建
public void show() {
JFrame frame = new JFrame();
// 创建一个工具栏
JButton but01 = new JButton("文件（F）");
JButton but02 = new JButton("编辑（E）");
JButton but03 = new JButton("查看（V）");
JButton but04 = new JButton("图像（I）");
JButton but05 = new JButton("颜色（C）");
JButton but06 = new JButton("帮助（H）");
JToolBar bar = new JToolBar();
bar.add(but01);
bar.add(but02);
bar.add(but03);
bar.add(but04);
bar.add(but05);
bar.add(but06);
frame.add(bar, BorderLayout.NORTH);
//创建颜色框的监听器
ActionListener a3 = new ActionListener(){
public void actionPerformed(ActionEvent e) {
//设置颜色
color = e.getActionCommand();
if(color.equals("Color.black") ){
g.setColor(Color.black);
lab.setBackground(Color.black);
}else if(color.equals("Color.gray")){
g.setColor(Color.gray);
lab.setBackground(Color.gray);
}else if(color.equals("Color.darkGray")){
g.setColor(Color.darkGray);
lab.setBackground(Color.darkGray);
}else if(color.equals("Color.green")){
g.setColor(Color.green);
lab.setBackground(Color.green);
}else if(color.equals("Color.LIGHT_GRAY")){
g.setColor(Color.LIGHT_GRAY);
lab.setBackground(Color.LIGHT_GRAY);
}else if(color.equals("Color.magenta")){
g.setColor(Color.magenta);
lab.setBackground(Color.magenta);
}else if(color.equals("Color.orange")){
g.setColor(Color.orange);
lab.setBackground(Color.orange);
}else if(color.equals("Color.pink")){
g.setColor(Color.pink);
lab.setBackground(Color.pink);
}else if(color.equals("Color.red")){
g.setColor(Color.red);
lab.setBackground(Color.red);
}else if(color.equals("Color.white")){
g.setColor(Color.white);
lab.setBackground(Color.white);
}
}
};
// 创建监听器
ActionListener al = new ActionListener() {
@Override
public void actionPerformed(ActionEvent e) {
biaozhi = e.getActionCommand();
}
};
// 创建工具面板
JPanel panel01 = new JPanel();
panel01.setPreferredSize(new Dimension(60, 104));
String[] arr = { "duobianxing", "Xjuxing", "ca", "tianchong", "dianbi",
"fangdajing", "huabi", "shuazi", "youqitong", "bianji",
"zhixian", "quxian", "juxing", "shouwei", "tuoyuan", "yuanji" };
for (int i = 0; i < arr.length; i++) {
ImageIcon img = new ImageIcon("DrawImages/" + arr[i] + ".jpg");
JButton but = new JButton(img);
but.setActionCommand(arr[i]);
but.addActionListener(al);
but.setPreferredSize(new Dimension(24, 22));
panel01.add(but);
}
frame.add(panel01, BorderLayout.WEST);
// 颜色选项栏
JPanel panel02 = new JPanel();
panel02.setPreferredSize(new Dimension(100, 50));
panel02.setLayout(null);
JPanel panel04 = new JPanel();
panel04.setPreferredSize(new Dimension(100, 40));
// panel04.setBackground(Color.white );
panel04.setLayout(new GridLayout(2, 5));
Color [] arr02={Color.black,Color.gray,Color.darkGray,Color.green,Color.LIGHT_GRAY,Color.magenta,
Color.orange,Color.pink,Color.red,Color.white};
String[] arr01 = {"Color.black","Color.gray","Color.darkGray","Color.green","Color.LIGHT_GRAY","Color.magenta",
"Color.orange","Color.pink","Color.red","Color.white"};
lab = new JLabel();
lab.setPreferredSize(new Dimension());
lab.setOpaque(true);
lab.setBackground(Color.black);
lab.setBounds(60, 0, 47, 50);
for (int i = 0; i < arr02.length; i++) {
JButton but = new JButton();
but.setBackground(arr02[i]);
but.setActionCommand(arr01[i]);
but.setPreferredSize(new Dimension(16, 16));
but.addActionListener(a3);
panel04.add(but);
}
panel02.add(lab);
panel04.setBounds(107, 0, 100, 50);
panel02.add(panel04);
frame.add(panel02, BorderLayout.SOUTH);
// 画布
JPanel panel03 = new JPanel();
panel03.setPreferredSize(new Dimension(694, 400));
panel03.setBackground(Color.WHITE);
frame.add(panel03, BorderLayout.CENTER);
frame.setTitle("画图板");
frame.setSize(754, 508);
frame.setResizable(false);
frame.setLocationRelativeTo(null);
frame.setDefaultCloseOperation(3);
MouseListener a1 = new MouseAdapter() {
// 鼠標按下時獲得坐标
public void mousePressed(MouseEvent e) {
x1 = e.getX();
y1 = e.getY();
}
// 鼠标松开时获取坐标
public void mouseReleased(MouseEvent e) {
x2 = e.getX();
y2 = e.getY();
if (biaozhi.equals("shouwei")) {
g.drawLine(x1, y1, x1, y1);
} else if (biaozhi.equals("dianbi")) {
} else if (biaozhi.equals("zhixian")) {
g.drawLine(x1, y1, x2, y2);
} else if (biaozhi.equals("juxing")) {
if (x2 > x1 && y2 > y1) {
x3 = x1;
y3 = y1;
w = Math.abs(x2 - x1);
h = Math.abs(y2 - y1);
g.drawRect(x3, y3, w, h);
} else if (x2 > x1 && y2 < y1) {
x3 = x1;
y3 = y2;
w = Math.abs(x2 - x1);
h = Math.abs(y2 - y1);
g.drawRect(x3, y3, w, h);
} else if (x2 < x1 && y2 < y1) {
x3 = x2;
y3 = y2;
w = Math.abs(x2 - x1);
h = Math.abs(y2 - y1);
g.drawRect(x3, y3, w, h);
} else {
x3 = x2;
y3 = y1;
w = Math.abs(x2 - x1);
h = Math.abs(y2 - y1);
g.drawRect(x3, y3, w, h);
}
} else if (biaozhi.equals("tuoyuan")) {
if (x2 > x1 && y2 > y1) {
x3 = x1;
y3 = y1;
w = Math.abs(x2 - x1);
h = Math.abs(y2 - y1);
g.drawOval(x3, y3, w, h);
} else if (x2 > x1 && y2 < y1) {
x3 = x1;
y3 = y2;
w = Math.abs(x2 - x1);
h = Math.abs(y2 - y1);
g.drawOval(x3, y3, w, h);
} else if (x2 < x1 && y2 < y1) {
x3 = x2;
y3 = y2;
w = Math.abs(x2 - x1);
h = Math.abs(y2 - y1);
g.drawOval(x3, y3, w, h);
} else {
x3 = x2;
y3 = y1;
w = Math.abs(x2 - x1);
h = Math.abs(y2 - y1);
g.drawOval(x3, y3, w, h);
}
} else if (biaozhi.equals("yuanji")) {
if (x2 > x1 && y2 > y1) {
x3 = x1;
y3 = y1;
w = Math.abs(x2 - x1);
h = Math.abs(y2 - y1);
g.drawRoundRect(x3, y3, w, h, 20, 20);
} else if (x2 > x1 && y2 < y1) {
x3 = x1;
y3 = y2;
w = Math.abs(x2 - x1);
h = Math.abs(y2 - y1);
g.drawRoundRect(x3, y3, w, h, 20, 20);
} else if (x2 < x1 && y2 < y1) {
x3 = x2;
y3 = y2;
w = Math.abs(x2 - x1);
h = Math.abs(y2 - y1);
g.drawRoundRect(x3, y3, w, h, 20, 20);
} else {
x3 = x2;
y3 = y1;
w = Math.abs(x2 - x1);
h = Math.abs(y2 - y1);
g.drawRoundRect(x3, y3, w, h, 20, 20);
}
}
}
};
// 添加拖動時的方法
MouseMotionListener a2 = new MouseMotionAdapter() {
public void mouseDragged(MouseEvent e) {
x3 = e.getX();
y3 = e.getY();
// 当鼠标在拖动时也要注意对坐标的赋值
if (biaozhi.equals("huabi")) {
g.drawLine(x1, y1, x3, y3);
x1 = x3;
y1 = y3;
} else if (biaozhi.equals("ca")) {
g.setColor(Color.white);
g.fillRect(x1, y1, 10, 20);
x1 = x3;
y1 = y3;
g.setColor(Color.black);
} else if (biaozhi.equals("shuazi")) {
g.fillRect(x1, y1, 5, 5);
x1 = x3;
y1 = y3;
} else if (biaozhi.equals("youqitong")) {
for (int i = 0; i < 20; i++) {
int j = (int) (Math.random() * 10);
int k = (int) (Math.random() * 10);
g.drawLine(x3 + j, y3 + k, x3 + j, y3 + k);
}
}
}
};
panel03.addMouseListener(a1);
panel03.addMouseMotionListener(a2);
frame.setVisible(true);
g = panel03.getGraphics();
}
public static void main(String[] args) {
DrawingBoard draw = new DrawingBoard();
draw.show();
}
}