Java示例：输入密钥。 Java新手

Question

感谢您花时间阅读本文，但我会简化它。我的问题是我有一个程序可以改变一种温度并将其转换为另一种温度。我想添加到程序中的是，当用户单击按钮时，当用户点击键盘上的“输入”时，它会在另一个框中显示新的温度。这是下面的代码：

import javax.swing.*; 
import javax.swing.event.*; 

import java.awt.*; 
import java.awt.event.*; 
import java.text.DecimalFormat; 
import java.util.InputMismatchException; 


public class Testlab { 

    static String celciusString = "Celcius"; 
    static String fahrenheitString = "Fahrenheit"; 
    static String kelvinString = "Kelvin"; 

    static String celcius1String = "Celcius2"; 
    static String fahrenheit1String = "Fahrenheit2"; 
    static String kelvin1String = "Kelvin2"; 

    private JLabel in = new JLabel("Input Scale"); 
    private JLabel out = new JLabel("Output Scale"); 

    private JLabel in1 = new JLabel("Input"); 
    private JLabel out1 = new JLabel("Output"); 

    private JTextField input = new JTextField(7); 
    private JTextField output = new JTextField(7); 

    private JFrame f = new JFrame("BasicGui"); // Create Frame 
    private JPanel pnlNorth = new JPanel(); //North Quadrant 
    private JPanel pnlSouth = new JPanel(); //South Quadrant 
    private JPanel pnlEast = new JPanel(); //East Quadrant 
    private JPanel pnlWest = new JPanel(); // West Quadrant 
    private JPanel pnlCenter = new JPanel(); // Center Quadrant 


    private JRadioButton celciusButton = new JRadioButton(celciusString); 
    private JRadioButton fahrenheitButton = new JRadioButton(fahrenheitString); 
    private JRadioButton kelvinButton = new JRadioButton(kelvinString); 

    private JRadioButton celcius1Button = new JRadioButton(celciusString); 
    private JRadioButton fahrenheit1Button = new JRadioButton(fahrenheitString); 
    private JRadioButton kelvin1Button = new JRadioButton(kelvinString); 

    //Menu 
    private JMenuBar mb = new JMenuBar(); // Menu Bar 
    private JMenu mnuFile = new JMenu("File"); // File Entry of Menu Bar 
    private JMenuItem mnuItemQuit = new JMenuItem("Quit"); // Quit Sub item 
    private JMenu mnuHelp = new JMenu("Help"); //Help Menu Entry 
    private JMenuItem mnuItemAbout = new JMenuItem("About"); //About Entry 

    //Constructor for GUI 
    public Testlab(){ 
     //Set Menubar 
     pnlEast.setLayout(new GridLayout (4,1)); 
     pnlWest.setLayout(new GridLayout (4,1)); 

     f.setJMenuBar(mb); 

     //Radio Button --New 
     celciusButton.setMnemonic(KeyEvent.VK_C); 
     celciusButton.setActionCommand(celciusString); 
     celciusButton.setSelected(true); 

     fahrenheitButton.setMnemonic(KeyEvent.VK_F); 
     fahrenheitButton.setActionCommand(fahrenheitString); 

     kelvinButton.setMnemonic(KeyEvent.VK_K); 
     kelvinButton.setActionCommand(kelvinString); 

     celcius1Button.setMnemonic(KeyEvent.VK_C); 
     celcius1Button.setActionCommand(celcius1String); 
     celcius1Button.setSelected(true); 

     fahrenheit1Button.setMnemonic(KeyEvent.VK_F); 
     fahrenheit1Button.setActionCommand(fahrenheit1String); 

     kelvin1Button.setMnemonic(KeyEvent.VK_K); 
     kelvin1Button.setActionCommand(kelvin1String); 

     //Group the radio Buttons. 

     ButtonGroup group = new ButtonGroup(); 
     group.add(celciusButton); 
     group.add(fahrenheitButton); 
     group.add(kelvinButton); 

     ButtonGroup group2 = new ButtonGroup(); 
     group2.add(celcius1Button); 
     group2.add(fahrenheit1Button); 
     group2.add(kelvin1Button); 


     //Register A listener for the radio Buttons. 
     celciusButton.addActionListener(new RadioButtonEvent()); 
     fahrenheitButton.addActionListener(new RadioButtonEvent()); 
     kelvinButton.addActionListener(new RadioButtonEvent()); 

     celcius1Button.addActionListener(new RadioButtonEvent()); 
     fahrenheit1Button.addActionListener(new RadioButtonEvent()); 
     kelvin1Button.addActionListener(new RadioButtonEvent()); 


     //Build Menus 
     mnuFile.add(mnuItemQuit); //Create Quit Line 
     mnuHelp.add(mnuItemAbout); //Create About Line 
     mb.add(mnuFile);  // Add Menu Items to form 
     mb.add(mnuHelp); 

     //Add Buttons 
     //pnlNorth.add(btnNorth); 

     pnlNorth.add(in1); 
     pnlSouth.add(out1); 
     pnlNorth.add(input); 
     pnlSouth.add(output); 

     pnlWest.add(in); 
     pnlWest.add(celciusButton); 
     pnlWest.add(fahrenheitButton); 
     pnlWest.add(kelvinButton); 

     pnlEast.add(out); 
     pnlEast.add(celcius1Button); 
     pnlEast.add(fahrenheit1Button); 
     pnlEast.add(kelvin1Button); 


     //Setup Main Frame 
     f.getContentPane().setLayout(new BorderLayout()); 
     f.getContentPane().add(pnlNorth, BorderLayout.NORTH); 
     f.getContentPane().add(pnlSouth,BorderLayout.SOUTH); 
     f.getContentPane().add(pnlEast,BorderLayout.EAST); 
     f.getContentPane().add(pnlWest,BorderLayout.WEST); 
     f.getContentPane().add(pnlCenter,BorderLayout.CENTER); 

     //Allows the Swing App to be closed 
     f.addWindowListener(new ListenCloseWdw()); 

     // Add Menu Listener 
     mnuItemQuit.addActionListener(new ListenMenuQuit()); 
    } 

    public class ListenMenuQuit implements ActionListener{ 
     public void actionPerformed(ActionEvent e){ 
      System.exit(0); 
     } 

    } 



    //NEW STUFF TO ADD 
    public class RadioButtonEvent implements ActionListener{ 
     public void actionPerformed(ActionEvent e){ 
      String action = e.getActionCommand(); 

      int temperture; 
      double newtemperture = 0.00; 
      try { 
      temperture = Integer.parseInt(input.getText()); 

     if (celciusButton.isSelected() & celcius1Button.isSelected()) 

      newtemperture = temperture; 


     else if (celciusButton.isSelected() & fahrenheit1Button.isSelected()) 

      newtemperture = ((temperture * 1.8)) + 32; 

      else if (celciusButton.isSelected() & kelvin1Button.isSelected()) 

       newtemperture = temperture + 273.15; 

      else if (fahrenheitButton.isSelected() & celcius1Button.isSelected()) 

       newtemperture = (temperture - 32) * .55555555555; 

      else if (fahrenheitButton.isSelected() & fahrenheit1Button.isSelected()) 

       newtemperture = temperture; 

      else if (fahrenheitButton.isSelected() & kelvin1Button.isSelected()) 

       newtemperture = (temperture + 459.67) * 5/9; 

      else if (kelvinButton.isSelected() & celcius1Button.isSelected()) 

       newtemperture = (temperture - 273.15); 

      else if (kelvinButton.isSelected() & fahrenheit1Button.isSelected()) 

       newtemperture = (temperture * 9/5) - 459.67; 

      else if (kelvinButton.isSelected() & kelvin1Button.isSelected()) 

       newtemperture = temperture; 


      } catch (Exception a) { 
       JOptionPane.showMessageDialog(null, "You did not input a value"); 
      } 



     output.setText(new DecimalFormat("##.##").format(newtemperture)); 
      } 
    } 



    public class ListenCloseWdw extends WindowAdapter{ 
     public void windowClosing(WindowEvent e){ 
      System.exit(0); 

     } 
    } 

    public void launchFrame(){ 
     //Display Frame 
     f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); 
     f.pack(); // Adjusting panel to components for Display 
     f.setVisible(true); 
    } 
    public static void main(String args[]){ 

     Testlab gui = new Testlab(); 
     gui.launchFrame(); 
    } 
} 

Answer 1

只需添加到Testlab()：

input.addActionListener(new RadioButtonEvent()); 

也没有为每个组件创建相同的ActionListeners。您只能创建一个并将其注册到任意数量的组件。