diceservice.java

HeadFirstCode系列图书里的源代码

import javax.swing.*;
import java.awt.event.*;
import java.io.*;

public class DiceService implements Service {

    JLabel label;
    JComboBox numOfDice;

    public JPanel getGuiPanel() {
       JPanel panel = new JPanel();
       JButton button = new JButton("Roll 'em!");
       String[] choices = {"1", "2", "3", "4", "5"};
       numOfDice = new JComboBox(choices);
       label = new JLabel("dice values here");
       button.addActionListener(new RollEmListener());
       panel.add(numOfDice);
       panel.add(button);
       panel.add(label);
       return panel;
    }

   public class RollEmListener implements ActionListener {
      public void actionPerformed(ActionEvent ev) {
         // roll the dice
         String diceOutput = "";
         String selection = (String)  numOfDice.getSelectedItem();
         int numOfDiceToRoll = Integer.parseInt(selection);
         for (int i = 0; i < numOfDiceToRoll; i++) {
            int r = (int) ((Math.random() * 6) + 1);
            diceOutput += (" " + r);
         }
        label.setText(diceOutput);
         
      }
    }
       
}