Java Swing实现简单的体重指数(BMI)计算器功能示例

package WeightIndex;
import javax.swing.*;
import javax.swing.border.EmptyBorder;
import java.awt.*;
import java.awt.event.*;
import java.text.DecimalFormat;
import java.util.regex.*;
public class WeightIndex extends JFrame {
 /**
  *
  */
 private static final long serialVersionUID = 1L;
 private JPanel contentPane;
 private JLabel titleLabel;
 private JPanel contentPanel;
 private JButton submitButton;
 private ButtonGroup bg;
 private JPanel sexPanel;
 private JRadioButton ChinaRadio;
 private JRadioButton AsiaRadio;
 private JRadioButton WHORadio;
 private JPanel whPanel;
 private JLabel heightLabel;
 private JLabel weightLabel;
 private JTextField heightText;
 private JTextField weightText;
 private JPanel consolePanel;
 private JLabel consoleLabel;
 private JTextField consoleText;
 private double weight;
 private double height;
 private double BMI;
 /**
  * Launch the application.
  */
 public static void main(String[] args) {
  EventQueue.invokeLater(new Runnable() {
   public void run() {
    try {
     WeightIndex frame = new WeightIndex();
     frame.pack();
     frame.setVisible(true);
    } catch (Exception e) {
     e.printStackTrace();
    }
   }
  });
 }
 /**
  * Create the frame.
  */
 public WeightIndex() {
  setTitle("脚本之家 - 身高体重指数计算器v1.0");
  setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
  setBounds(100, 100, 450, 300);
  //主容器
  contentPane = new JPanel();
  contentPane.setBorder(new EmptyBorder(5, 5, 5, 5));
  contentPane.setLayout(new BorderLayout(0, 0));
  setContentPane(contentPane);
  //标题，主容器北
  titleLabel = new JLabel("身高体重指数计算器");
  titleLabel.setHorizontalAlignment(SwingConstants.CENTER);
  contentPane.add(titleLabel, BorderLayout.NORTH);
  //存放选项的panel，主容器中
  contentPanel = new JPanel();
  contentPanel.setLayout(new BorderLayout());
  contentPane.add(contentPanel,BorderLayout.CENTER);
  //提交按钮，主容器南
  submitButton = new JButton("计算");
  contentPane.add(submitButton, BorderLayout.SOUTH);
  //存放性别选择的panel，选项北
  bg = new ButtonGroup();
  sexPanel = new JPanel();
  sexPanel.setLayout(new FlowLayout());
  contentPanel.add(sexPanel,BorderLayout.NORTH);
  ChinaRadio = new JRadioButton("中国标准");
  ChinaRadio.setSelected(true);
  AsiaRadio = new JRadioButton("亚洲标准");
  WHORadio = new JRadioButton("WHO（世界卫生组织）标准");
  bg.add(ChinaRadio);
  bg.add(AsiaRadio);
  bg.add(WHORadio);
  sexPanel.add(ChinaRadio);
  sexPanel.add(AsiaRadio);
  sexPanel.add(WHORadio);
  //存放身高体重的panel，选项中
  whPanel = new JPanel();
  whPanel.setLayout(new FlowLayout());
  contentPanel.add(whPanel,BorderLayout.CENTER);
  heightLabel = new JLabel("身高（米/m）：");
  weightLabel = new JLabel("体重（千克/kg）：");
  heightText = new JTextField(10);
  heightText.setToolTipText("请输入身高");
  weightText = new JTextField(10);
  weightText.setToolTipText("请输入体重");
  whPanel.add(heightLabel);
  whPanel.add(heightText);
  whPanel.add(weightLabel);
  whPanel.add(weightText);
  //结果
  consolePanel = new JPanel();
  consolePanel.setLayout(new FlowLayout());
  consoleLabel = new JLabel("你的身体质量指数为：");
  consoleText = new JTextField(28);
  consoleText.setEditable(false);
  consolePanel.add(consoleLabel);
  consolePanel.add(consoleText);
  contentPanel.add(consolePanel,BorderLayout.SOUTH);
  submitButton.addActionListener(new ActionListener(){
   public void actionPerformed(ActionEvent e) {
    String hstr = heightText.getText();
    String wstr = weightText.getText();
    Pattern pattern = Pattern.compile("^[0-9]+(.[0-9]+)?$");
    Matcher hisNum = pattern.matcher(hstr);
    Matcher wisNum = pattern.matcher(wstr);
    boolean acc = true;
    if( !hisNum.matches()|| !wisNum.matches()){
      acc = false;
    }
    if(acc)
    {
     height = Double.parseDouble(hstr);
     weight = Double.parseDouble(wstr);
     BMI = weight / (height*height);
     DecimalFormat df = new DecimalFormat("#.0");
     String out = "";
     if(ChinaRadio.isSelected())
     {
      if(BMI<18.5)
       out = "偏瘦，瘦骨嶙峋的，多吃点吧！";
      else if(BMI<23.9)
       out = "正常，棒棒哒！";
      else if(BMI<28)
       out = "偏胖，你胖你就运动减肥！";
      else if(BMI>=28)
       out = "肥胖，现在减肥来的及！";
      else
       out ="外星人派来的你哦，请重新输入！";
     }
     else if(AsiaRadio.isSelected())
     {
      if(BMI<18.5)
       out = "偏瘦，瘦骨嶙峋的，多吃点吧！";
      else if(BMI<22.9)
       out = "正常，棒棒哒！";
      else if(BMI<24.9)
       out = "偏胖，你胖你就运动减肥！";
      else if(BMI<30)
       out = "肥胖，现在减肥来的及！";
      else if(BMI>=30)
       out = "重度肥胖，不是一般人，赶紧减肥吧！";
      else
       out ="外星人派来的你哦，请重新输入！";
     }
     else
     {
      if(BMI<18.5)
       out = "偏瘦，瘦骨嶙峋的，多吃点吧！";
      else if(BMI<24.9)
       out = "正常，棒棒哒！";
      else if(BMI<29.9)
       out = "偏胖，你胖你就运动减肥！";
      else if(BMI<34.9)
       out = "肥胖，现在减肥来的及！";
      else if(BMI<39.9)
       out = "重度肥胖，不是一般人，赶紧减肥吧！";
      else if(BMI>=40)
       out = "极重度肥胖,那可能得去医院看看咯！";
      else
       out ="外星人派来的你哦，请重新输入！";
     }
     consoleText.setText("你的指数为："+df.format(BMI)+"，你的健康状况为："+out);
    }
   }
  });
 }
}