spherewindow.java

mvc模式的示例代码。输入球的半径

import javax.swing.*;
import java.awt.event.*;
/**
 * <p>Title: SphereWindow</p>
 * <p>Description: The Controller part of the model-view paradigm</p>
 * <p>Copyright: Copyright (c) 2005</p>
 * @author Smart Lee
 * @version 1.1
 */
public class SphereWindow extends SphereFrame implements
    ActionListener, MouseListener, MouseMotionListener{

  // 创建视图一
  TextView tView = new TextView();
  // 创建视图二
  GraphicsView gView = new GraphicsView();
  // 创建模型
  Sphere model = new Sphere();

  //Construct the application
  public SphereWindow() {
    try {
      jbInit();
    }
    catch(Exception e) {
      e.printStackTrace();
    }
  }
  //Main method
  public static void main(String[] args) {
    try {
   UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
    }
    catch(Exception e) {
      e.printStackTrace();
    }
    new SphereWindow();
  }
  private void jbInit() throws Exception {
    // 添加视图
    contentPane.add(tView);
    contentPane.add(gView);
    this.setVisible(true);
    // 建立模型与视图一的关联
    model.addObserver(tView);
    tView.update(model, null);
    // 建立模型与视图二的关联
    model.addObserver(gView);
    gView.update(model, null);
    // 为视图一各控件添加事件监听器
    tView.radiusTextField.addActionListener(this);
    tView.volumeTextField.addActionListener(this);
    tView.surfAreaTextField.addActionListener(this);
    // 为视图二添加鼠标事件
    gView.addMouseListener(this);
    gView.addMouseMotionListener(this);
  }
  public void actionPerformed(ActionEvent e) {
    if (e.getSource() == tView.radiusTextField) {
      JTextField jtf = (JTextField)e.getSource();
      // 捕获异常字符
      try {
        double radius = Double.parseDouble(jtf.getText());
        // 更改模型数据
        model.setRadius(radius);
      } catch (Exception ex) {
        JOptionPane.showMessageDialog(null,"illegal character!");
      }
      // 调用视图二的绘图方法以更新视图
      gView.repaint();
    }
    if (e.getSource() == tView.volumeTextField) {
      JTextField jtf = tView.volumeTextField;
      try {
        double volume = Double.parseDouble(jtf.getText());
        model.setVolume(volume);
      } catch(Exception ex) {
          JOptionPane.showMessageDialog(null,"illegal character!");
      }
      gView.repaint();
    }
    if (e.getSource() == tView.surfAreaTextField) {
      JTextField jtf = (JTextField)e.getSource();
      try {
        double surfArea = Double.parseDouble(jtf.getText());
        model.setSuArea(surfArea);
      } catch(Exception ex) {
        JOptionPane.showMessageDialog(null,"illegal character!");
      }
      gView.repaint();
    }
  }
  public void mousePressed(MouseEvent e) {
    int X = gView.getWidth() / 2;
    int Y = gView.getHeight() / 2;
    gView.bShowDim = true; // 控制是否显示点坐标
    gView.x = e.getX();
    gView.y = e.getY();
    // 圆心坐标(X, Y)
    gView.radius = pointDistance(gView.x, gView.y, X, Y);
    // 更改数据模型
    model.setRadius(gView.radius);
    gView.repaint();
  }
  public void mouseReleased(MouseEvent e) {
    // 鼠标离开时不再显示点坐标
    gView.bShowDim = false;
    gView.repaint();
  }
  public void mouseEntered(MouseEvent e) {

    }
  public void mouseExited(MouseEvent e) {

  }
  public void mouseClicked(MouseEvent e) {

    }
  public void mouseMoved(MouseEvent e) {

    }
  public void mouseDragged(MouseEvent e) {
    int X = gView.getWidth() / 2;
    int Y = gView.getHeight() / 2;
    gView.bShowDim = true;
    gView.x = e.getX();
    gView.y = e.getY();
    gView.radius = pointDistance(gView.x, gView.y, X, Y);
    model.setRadius(gView.radius);
    gView.repaint();
  }
  /**
   * 求两点距离
   * @param x1 double 点1的横坐标
   * @param y1 double 点1的纵坐标
   * @param x2 double 点2的横坐标
   * @param y2 double 点2的纵坐标
   * @return double
   */
  protected double pointDistance(double x1, double y1, double x2, double y2) {
    return Math.pow(((x1 - x2) * (x1 - x2) + (y1 - y2) * (y1 - y2)), 1/2.0);
  }

}