package GraphicsCanvas; import java.awt.BorderLayout; import java.awt.Canvas; import java.awt.Color; import java.awt.Graphics; import java.awt.Image; import java.awt.event.ActionEvent; import java.awt.event.ActionListener; import javax.swing.JButton; import javax.swing.JFrame; import javax.swing.JLabel; import javax.swing.JPanel; import javax.swing.JTextField; import javax.swing.Timer; import javax.swing.UIManager; /**  * 模拟血压计类,高压、低压  *  * @author 樊俊彬  * @Time 2013-12-10  */ public class Blood extends JFrame {  private static final long serialVersionUID = 1L;  private Image iBuffer;  private MyCanvas bloodCanvas = new MyCanvas();  private JTextField highPressText, lowPressText;  // 画布长宽  private final int CANVAS_WIDTH = 400;  private final int CANVAS_HEIGHT = 800;  // 玻璃外壳长宽与起始坐标  private final int BLOOD_WIDTH = 30;  private final int BLOOD_HEIGHT = 650;  private final int BLOOD_X = CANVAS_WIDTH / 2 - BLOOD_WIDTH / 2;  private final int BLOOD_Y = 50;  // 框架大小与起始坐标  private final int FRAME_WIDTH = 120;  private final int FRAME_HEIGHT = 720;  private final int FRAME_X = CANVAS_WIDTH / 2 - FRAME_WIDTH / 2;  private final int FRAME_Y = BLOOD_Y - 20;  // 0刻度线的横纵坐标与长度  private final int ZORELINE_Y = BLOOD_Y + BLOOD_HEIGHT - 10;  private final int ZORELINE_X = CANVAS_WIDTH / 2 + BLOOD_WIDTH / 2;  private final int LINE_LENGTH = 8;  // 输入的高压、低压  private int highPressInput, lowPressInput;  // 高、低压水银柱的动态高度  int highPressHeight = 0;  int lowPressHeight = 0;  int startLow = BLOOD_Y;  // 高、低水银计时器  Timer highPressTimer, lowPressTimer;  public Blood() {   super("自定义血压计模型-FreeDoman");   this.setDefaultCloseOperation(EXIT_ON_CLOSE);   this.setBounds(300, 50, CANVAS_WIDTH, CANVAS_HEIGHT + 20);   // 添加控制到框架北部区   JPanel topPanel = new JPanel();   this.add(topPanel, BorderLayout.NORTH);   highPressText = new JTextField(5);   lowPressText = new JTextField(5);   JButton pressButton = new JButton("显示");   pressButton.addActionListener(new ActionListener() {    @Override    public void actionPerformed(ActionEvent arg0) {     highPressInput = Integer.parseInt(highPressText.getText());     lowPressInput = Integer.parseInt(lowPressText.getText());     ActionListener highPressTaskPerformer = new ActionListener() {      public void actionPerformed(ActionEvent evt) {       // 高度增加 1像素/0.01s,只到满足输入的要求,停止计时       highPressHeight += 1;       bloodCanvas.repaint();       if (highPressHeight == highPressInput * 2) {        highPressTimer.stop();        // 低压水银柱计时器嵌套于高压计时器内部,有先后顺序(高压先走,后低压)        startLow = ZORELINE_Y - highPressHeight;        ActionListener lowPressTaskPerformer = new ActionListener() {         public void actionPerformed(ActionEvent evt) {          lowPressHeight += 1;          bloodCanvas.repaint();          if (lowPressHeight == ZORELINE_Y            - lowPressInput * 2 - startLow)           lowPressTimer.stop();         }        };        lowPressTimer = new Timer(10, lowPressTaskPerformer);        lowPressTimer.start();       }      }     };     // 定义每0.01秒执行一次的事件监听器     highPressTimer = new Timer(10, highPressTaskPerformer);     highPressTimer.start();    }   });   topPanel.add(new JLabel("高压值", JLabel.CENTER));   topPanel.add(highPressText);   topPanel.add(new JLabel("低压值", JLabel.CENTER));   topPanel.add(lowPressText);   // topPanel.add(new JLabel("心率", JLabel.CENTER));   topPanel.add(pressButton);   // 添加画布到中央区   this.add(bloodCanvas, BorderLayout.CENTER);   this.setResizable(false);   this.setVisible(true);  }  /**   * 画布重绘血压计   */  class MyCanvas extends Canvas {   public void paint(Graphics g) {    // 画边框    g.setColor(Color.BLACK);    g.draw3DRect(FRAME_X, FRAME_Y, FRAME_WIDTH, FRAME_HEIGHT, true);    // 画玻璃外壳    g.setColor(Color.ORANGE);    g.fill3DRect(BLOOD_X, BLOOD_Y, BLOOD_WIDTH, BLOOD_HEIGHT, true);    // 高压水银柱    g.setColor(Color.RED);    g.fill3DRect(BLOOD_X, ZORELINE_Y - highPressHeight, BLOOD_WIDTH,      highPressHeight, true);    // 低压高压水银柱    g.setColor(Color.ORANGE);    g.fill3DRect(BLOOD_X, startLow, BLOOD_WIDTH, lowPressHeight, true);    // 画底部水银圆球    g.setColor(Color.RED);    g.fillOval(CANVAS_WIDTH / 2 - 30, ZORELINE_Y - 5, 60, 60);    // 右侧0刻度线起始刻度与坐标(刻度线纵坐标以line_y渐变)    int rightStartDegree = 0;    int line_y = ZORELINE_Y;    for (; line_y > BLOOD_Y; line_y -= 2) {     // 2个像素点为一个最小分度 1度     g.setColor(Color.BLACK);     g.drawLine(ZORELINE_X, line_y, ZORELINE_X + LINE_LENGTH, line_y);     // 每隔10最小分度个画10度刻度线     if (line_y % 20 == 10) {      g.setColor(Color.BLUE);      g.drawLine(ZORELINE_X, line_y,        ZORELINE_X + LINE_LENGTH * 2, line_y);      g.drawString(rightStartDegree + "", ZORELINE_X        + LINE_LENGTH * 3, line_y + 4);      rightStartDegree += 10;     }    }    // 左侧0刻度线起始刻度与坐标(刻度线纵坐标以line_y渐变)    int leftStartDegree = 0;    int leftLine_y = ZORELINE_Y;    for (; leftLine_y > BLOOD_Y; leftLine_y -= 6) {     // 6个像素点为一个最小分度 1度     g.setColor(Color.BLACK);     g.drawLine(BLOOD_X, leftLine_y, BLOOD_X - LINE_LENGTH,       leftLine_y);     // 每隔10最小分度个画10度刻度线     if (leftLine_y % 20 == 10) {      g.setColor(Color.BLUE);      g.drawLine(BLOOD_X, leftLine_y, BLOOD_X - LINE_LENGTH * 2,        leftLine_y);      g.drawString(leftStartDegree + "", BLOOD_X - LINE_LENGTH        * 4, leftLine_y + 4);      leftStartDegree += 10;     }    }   }   /**    * 双缓冲技术：复杂的计算速度慢于屏幕显示，用缓冲解决屏幕闪烁问题    */   @Override   public void update(Graphics g) {    if (iBuffer == null) {     iBuffer = createImage(this.getSize().width,       this.getSize().height);    }    Graphics gBuffer = iBuffer.getGraphics();    gBuffer.setColor(getBackground());    gBuffer.fillRect(0, 0, this.getSize().width, this.getSize().height);    paint(gBuffer);    gBuffer.dispose();    g.drawImage(iBuffer, 0, 0, this);   }  }  public static void main(String[] args) {   // 设置界面的外观，为系统外观   try {    UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());   } catch (Exception e) {    e.printStackTrace();   }   new Blood();  } }