我正在编写一个带有测验元素的程序，当用户得到错误答案时，会给出反馈。问题JFrame由具有实际问题的JLabel和4个具有不同选项的JRadioButtons组成（名为rad1，rad2，rad3，rad4）。我尝试做的是，如果用户出现错误，则具有正确答案背景颜色的单选按钮变为绿色，单选按钮具有用户给出的答案背景变为红色。
这是我用来确定哪些答案正确的FOR循环：
private void btnSubmitActionPerformed(java.awt.event.ActionEvent evt) {
System.out.println("Submit Clicked");
//figures out what choice the user selected
String correctAnswer = questions.get(current).getAnswer();
int numChoice = -1;
String choice = "";
boolean answered = false;
if (rad1.isSelected()) {
numChoice = 0;
answered = true;
choice = rad1.getText();
} else if (rad2.isSelected()) {
numChoice = 1;
answered = true;
choice = rad2.getText();
} else if (rad3.isSelected()) {
numChoice = 2;
answered = true;
choice = rad3.getText();
} else if (rad4.isSelected()) {
numChoice = 3;
answered = true;
choice = rad4.getText();
} else { //user didn't pick a choice
JOptionPane.showMessageDialog(null, "You didn't answer the question, try again!");
}
if (choice.equals(correctAnswer)) {
score++;
System.out.println("score++");
} else {
//figures out which of the answers was correct
rad1.setBackground(Color.RED);
for (int i = 0; i < 4; i++) {
if (questions.get(current).getChoices()[i].equals(correctAnswer)) {
System.out.println(correctAnswer);
System.out.println(i);
//me trying to see if it will change if I put it outside the switch
//confirmed that it will not.
rad1.setBackground(Color.RED);
switch (i) {
case 0:
rad1.setBackground(new Color(51, 204, 51));
break;
case 1:
rad2.setBackground(new Color(51, 204, 51));
break;
case 2:
rad3.setBackground(new Color(51, 204, 51));
break;
case 3:
rad4.setBackground(new Color(51, 204, 51));
break;
}
break;
}
}
switch (numChoice) {
case 0:
rad1.setBackground(new Color(153, 0, 0));
break;
case 1:
rad2.setBackground(new Color(153, 0, 0));
break;
case 2:
rad3.setBackground(new Color(153, 0, 0));
break;
case 3:
rad4.setBackground(new Color(153, 0, 0));
break;
}
}
//loads next question
//loads the next question
if (current < 10) {
updateFrame();
} else {
//ends the quiz
}
}
我一直在玩.setBackground（）方法一段时间，如果我将print语句放在case块中，它们会执行，但着色并没有发生。我有什么东西是愚蠢的吗？
由于
编辑：添加了更多代码，以查看FOR循环是否在btnSubmitActionPerformed（）方法中。当用户点击该按钮时，将判断他们的答案并且要改变单选按钮的颜色。
答案 0 :(得分：1)
立即想到两件事：
尝试设置一些其他属性，例如大小，只是为了看看你是否得到了结果。如果是这样，那么问题是单选按钮没有背景，你将不得不想出另一种设计。如果没有任何反应，那么这可能是第一个问题。
答案 1 :(得分：1)
您希望代码过于复杂且不必要。我自己，我会尝试“OOP-ify”来减少圈复杂度并且
List<String>表示不正确的答案。 public List<String> getShuffledAnswers()返回一个字符串列表，其中包含正确和错误的所有答案，并在自己的列表中随机播放，testAnswer(String test)的布尔方法，并且返回测试的true等于correctAnswer。 然后我创建一个名为QuestionPanel的JPanel
例如：
import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.GridLayout;
import java.awt.event.ActionEvent;
import java.util.ArrayList;
import java.util.Collections;
import java.util.List;
import javax.swing.AbstractAction;
import javax.swing.BorderFactory;
import javax.swing.ButtonGroup;
import javax.swing.ButtonModel;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JOptionPane;
import javax.swing.JPanel;
import javax.swing.JRadioButton;
import javax.swing.SwingUtilities;
@SuppressWarnings("serial")
public class TestQuestions extends JPanel {
private static final Question TEST_QUESTION = new Question("Select the Correct Answer", "This answer is correct",
"Incorrect Answer 1", "Incorrect Answer 2", "Incorrect Answer 3");
private QuestionPanel questionPanel = new QuestionPanel();
public TestQuestions() {
questionPanel.setQuestion(TEST_QUESTION);
JButton testAnswerBtn = new JButton(new AbstractAction("Test Answer") {
@Override
public void actionPerformed(ActionEvent e) {
boolean isCorrect = questionPanel.isCorrectAnswerSelected();
String message = "";
if (isCorrect) {
message = "Correct answer selected!";
} else {
message = "Incorrect answer selected!";
}
JOptionPane.showMessageDialog(TestQuestions.this, message);
questionPanel.displayCorrectWrongAnswers();
}
});
JButton clearAllBtn = new JButton(new AbstractAction("Clear All") {
@Override
public void actionPerformed(ActionEvent e) {
questionPanel.clearAll();
questionPanel.clearSelection();
}
});
JPanel btnPanel = new JPanel(new GridLayout(1, 0, 5, 5));
btnPanel.add(testAnswerBtn);
btnPanel.add(clearAllBtn);
setBorder(BorderFactory.createEmptyBorder(5, 5, 5, 5));
setLayout(new BorderLayout(5, 5));
add(questionPanel, BorderLayout.CENTER);
add(btnPanel, BorderLayout.PAGE_END);
}
private static void createAndShowGui() {
JFrame frame = new JFrame("TestQuestions");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.getContentPane().add(new TestQuestions());
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable() {
public void run() {
createAndShowGui();
}
});
}
}
@SuppressWarnings("serial")
class QuestionPanel extends JPanel {
private static final Color CORRECT_ANSWER_SELECTED_COLOR = new Color(151, 255, 151);
private static final Color CORRECT_ANSWER_NOT_SELECTED_COLOR = new Color(151,151, 255);
private static final Color INCORRECT_ANSWER_SELECTED_COLOR = new Color(255, 151, 151);
private Question question;
private JLabel questionTextLabel = new JLabel();
private List<JRadioButton> answerButtonList = new ArrayList<>();
private JPanel answerPanel = new JPanel(new GridLayout(0, 1));
private ButtonGroup buttonGroup = new ButtonGroup();
public QuestionPanel() {
setLayout(new BorderLayout());
add(questionTextLabel, BorderLayout.PAGE_START);
add(answerPanel, BorderLayout.CENTER);
}
public void setQuestion(Question question) {
this.question = question;
questionTextLabel.setText(question.getQuestionText());
answerPanel.removeAll();
answerButtonList.clear();
buttonGroup = new ButtonGroup();
for (String answer : question.getShuffledAnswers()) {
JRadioButton rBtn = new JRadioButton(answer);
rBtn.setActionCommand(answer);
answerButtonList.add(rBtn);
buttonGroup.add(rBtn);
answerPanel.add(rBtn);
}
}
public boolean isCorrectAnswerSelected() {
ButtonModel model = buttonGroup.getSelection();
if (model == null) {
return false; // nothing selected
} else {
return question.checkAnswer(model.getActionCommand());
}
}
public void clearAll() {
for (JRadioButton jRadioButton : answerButtonList) {
jRadioButton.setOpaque(false);
jRadioButton.setBackground(null);
}
}
public void clearSelection() {
buttonGroup.clearSelection();
}
public void displayCorrectWrongAnswers() {
clearAll();
for (JRadioButton jRadioButton : answerButtonList) {
if (jRadioButton.isSelected()) {
jRadioButton.setOpaque(true);
if (question.checkAnswer(jRadioButton.getActionCommand())) {
jRadioButton.setBackground(CORRECT_ANSWER_SELECTED_COLOR);
} else {
jRadioButton.setBackground(CORRECT_ANSWER_NOT_SELECTED_COLOR);
}
} else if (question.checkAnswer(jRadioButton.getActionCommand())) {
jRadioButton.setOpaque(true);
jRadioButton.setBackground(INCORRECT_ANSWER_SELECTED_COLOR);
}
}
}
}
class Question {
private String questionText;
private String correctAnswer;
private List<String> incorrectAnswerList = new ArrayList<>();
public Question(String questionText, String correctAnswer, String... incorrectAnswers) {
this.questionText = questionText;
this.correctAnswer = correctAnswer;
for (String incorrectAnswer : incorrectAnswers) {
incorrectAnswerList.add(incorrectAnswer);
}
}
public String getQuestionText() {
return questionText;
}
public String getCorrectAnswer() {
return correctAnswer;
}
public List<String> getShuffledAnswers() {
List<String> answers = new ArrayList<>(incorrectAnswerList);
answers.add(correctAnswer);
Collections.shuffle(answers);
return answers;
}
public boolean checkAnswer(String test) {
return correctAnswer.equalsIgnoreCase(test);
}
}