我如何做才能让我的测验让我回答？

Question

我是一个初学者，我正在尝试编写一个简单的程序，先问一个问题，然后提示您在输入对话框中输入“ A”，“ B”或“ C”的形式回答该问题，但没有对话框出现。 其他一切似乎都正常。

这是我的代码：

package homework;

import javax.swing.JOptionPane;

public class Quiz {

    public static void main(String[] args) 
    {


    int x = 0;
    String[] quizQuestion = {"What is the color of the sky?", "What is the         
        color of the sea?", "What is the color of the earth?"};
    int score = 0;
    String correct = "You are correct";
    String incorrect = "You are incorrect";
    String playerAnswerString = " ";
    playerAnswerString.toUpperCase();
    char playerAnswer = playerAnswerString.charAt(0);

    JOptionPane.showMessageDialog(null, "Test Your Knowledge!");
    JOptionPane.showMessageDialog(null, "Select an answer to the questions.");
    for(x = 0; x < 3; x++)
    {
        JOptionPane.showMessageDialog(null, quizQuestion[x]);
        while(quizQuestion.equals(0))
        {
            playerAnswerString = JOptionPane.showInputDialog(null, "A = Blue, B = Green, C = Brown");
            if(playerAnswer == 'A')
            {
                JOptionPane.showMessageDialog(null, correct);
                score++;
            }
            else
            {
                JOptionPane.showMessageDialog(null, incorrect);
            }
        }
        while(quizQuestion.equals(1))
        {
            playerAnswerString = JOptionPane.showInputDialog(null, "A = Blue, B = Green, C = Brown");
            if(playerAnswer == 'B')
            {
                JOptionPane.showMessageDialog(null, correct);
                score++;
            }
            else
            {
                JOptionPane.showMessageDialog(null, incorrect);
            }
        }
        while(quizQuestion.equals(2))
        {
            playerAnswerString = JOptionPane.showInputDialog(null, "A = Blue, B = Green, C = Brown");
            if(playerAnswer == 'C')
            {
                JOptionPane.showMessageDialog(null, correct);
                score++;
            }
            else
            {
                JOptionPane.showMessageDialog(null, incorrect);
            }
        }
    }
    JOptionPane.showMessageDialog(null, "You scored " + score + "/3.");


}
}

提前致谢。

为清楚起见进行了编辑。

Answer 1

char playerAnswer = playerAnswerString.charAt(0);

用户在此处选择答案后，必须分配playerAnswer的值

playerAnswerString = JOptionPane.showInputDialog(null, "A = Blue, B = Green, C = Brown");

否则变量playerAnswer将为空

Answer 2

所做的修改很少，请检查并让我知道代码是否按您的期望工作。

 import javax.swing.JOptionPane;

public class Quiz {

    public static void main(String[] args) 
    {


    int x = 0;
    String[] quizQuestion = {"What is the color of the sky?", "What is the       color of the sea?", "What is the color of the earth?"};
    int score = 0;
    String correct = "You are correct";
    String incorrect = "You are incorrect";
    String playerAnswerString = " ";
    playerAnswerString.toUpperCase();
    char playerAnswer = playerAnswerString.charAt(0);

    JOptionPane.showMessageDialog(null, "Test Your Knowledge!");
    JOptionPane.showMessageDialog(null, "Select an answer to the questions.");
    for(x = 0; x < 3; x++)
    {


        JOptionPane.showMessageDialog(null, quizQuestion[x]);
        if(x==0)
        {
            playerAnswerString = JOptionPane.showInputDialog(null, "A = Blue, B = Green, C = Brown");

            System.out.println(playerAnswerString+"   "+playerAnswer);

            if(playerAnswerString.equals("A"))
            {
                JOptionPane.showMessageDialog(null, correct);
                score++;
            }
            else
            {
                JOptionPane.showMessageDialog(null, incorrect);
            }
        }
        if(x==1)
        {
            playerAnswerString = JOptionPane.showInputDialog(null, "A = Blue, B = Green, C = Brown");
            if(playerAnswerString.equals("B"))
            {
                JOptionPane.showMessageDialog(null, correct);
                score++;
            }
            else
            {
                JOptionPane.showMessageDialog(null, incorrect);
            }
        }
        if(x==2)
        {
            playerAnswerString = JOptionPane.showInputDialog(null, "A = Blue, B = Green, C = Brown");
            if(playerAnswerString.equals("C"))
            {
                JOptionPane.showMessageDialog(null, correct);
                score++;
            }
            else
            {
                JOptionPane.showMessageDialog(null, incorrect);
            }
        }
    }
    JOptionPane.showMessageDialog(null, "You scored " + score + "/3.");


}
}