好的，这是我的问题。我正在研究一个使用问题计数器显示10个问题的琐事游戏，一旦发生这种情况，就会调用finalscore类。我已经实现了一个计时器，可以为每个问题重置一次，如果时间到了，就会进入下一个问题。但是，如果在最后一个问题上没有点击任何内容，即使在开始新游戏之后它也将继续循环回到finalscore类。
public class game extends Activity implements OnClickListener {
// int[] anArray;
int[] anArray2 = { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 };
int numberOfQuestionsDisplayedCounter = 0;
int nextOrFinishValue = 0;
int randomValueZeroToThree = 0;
int randomValue0to29 = 0;
boolean alreadyDisplayQuestion = false;
boolean validQuestionNumber = false;
boolean rightButton1 = false;
boolean rightButton2 = false;
boolean rightButton3 = false;
boolean rightButton4 = false;
String questionFromDatabase;
String answer1FromDatabase;
String answer2FromDatabase;
String answer3FromDatabase;
String answer4FromDatabase;
String displayedQuestionFromDatabase = "question ";
String displayedAnswer1FromDatabase = "answer1a ";
String displayedAnswer2FromDatabase = "answer2a ";
String displayedAnswer3FromDatabase = "answer3a ";
String displayedAnswer4FromDatabase = "answer4a ";
int categoryId = 0;
int questionId = 0;
int currentScore = 0;
private CountDownTimer mCountDown;
public void onCreate(Bundle savedInstanceState) {
int randomInt = 1;
super.onCreate(savedInstanceState);
categoryId = com.triviagame.Trivia_Game.categoryIdInMainMenu;
// System.out.println("categoryID =" + categoryId);
setContentView(R.layout.displayquestion);
// gathers question and answers from database
gatherInfoBeforePopulating(); // includes generating random number
// between getting info from database 1
// to 30
// displays question, answers, score
populateWithQuestionInfo(displayedQuestionFromDatabase,
displayedAnswer1FromDatabase, displayedAnswer2FromDatabase,
displayedAnswer3FromDatabase, displayedAnswer4FromDatabase,
nextOrFinishValue);
// Sets buttons and listers for the buttons with the 4 possible answers
View answer1button = findViewById(R.id.answer1button);
answer1button.setOnClickListener(this);
View answer2button = findViewById(R.id.answer2button);
answer2button.setOnClickListener(this);
View answer3button = findViewById(R.id.answer3button);
answer3button.setOnClickListener(this);
View answer4button = findViewById(R.id.answer4button);
answer4button.setOnClickListener(this);
final TextView myCounter = (TextView) findViewById(R.id.tv);
mCountDown = new CountDownTimer(21000, 1000) {
@Override
public void onFinish() {
questionCheck();
resetTimer();
}
@Override
public void onTick(long millisUntilFinished) {
myCounter.setText("Time left: "
+ String.valueOf(millisUntilFinished / 1000));
}
}.start();
}
// Displays question, answers, score
public void populateWithQuestionInfo(String question, String answer1,
String answer2, String answer3, String answer4,
int nextQuestionOrFinish) {
// populate the question label
TextView questionLabel = (TextView) findViewById(R.id.question);
questionLabel.setText(question);
// populate answer1
Button buttonAnswer1 = (Button) findViewById(R.id.answer1button);
buttonAnswer1.setText(answer1);
// populate answer2
Button buttonAnswer2 = (Button) findViewById(R.id.answer2button);
buttonAnswer2.setText(answer2);
// populate answer3
Button buttonAnswer3 = (Button) findViewById(R.id.answer3button);
buttonAnswer3.setText(answer3);
// populate answer4
Button buttonAnswer4 = (Button) findViewById(R.id.answer4button);
buttonAnswer4.setText(answer4);
numberOfQuestionsDisplayedCounter++;
}
// Generates a random number between 0 and 3 to be used to display the
// possible answers randomly
int RandomGeneratorZeroToThree() {
int randomInt = 0;
Random randomGenerator = new Random();
for (int idx = 1; idx <= 10; ++idx) {
randomInt = randomGenerator.nextInt(4);
}
return randomInt;
}
// Generates a random number between 0 and 29 to be used to select the
// question to be displayed
int RandomGenerator0To29() {
int randomInt2 = 0;
Random randomGenerator2 = new Random();
for (int idx2 = 1; idx2 <= 10; ++idx2) {
randomInt2 = randomGenerator2.nextInt(30);
}
return randomInt2;
}
// returns true if the question has already been displayed
// returns false if the question has not been already displayed
boolean questionsAlreadyDisplayed(int randomValue0to29) {
for (int i = 0; i < 10; i++) {
if (anArray2[i] == randomValue0to29) {
return true; // question already displayed
}
}
anArray2[numberOfQuestionsDisplayedCounter] = randomValue0to29; // questionId
// added
// to
// array
// of
// displayed
// questions
return false; // random number can be used as it has been used already
}
// Connects to the database to gather the question and 4 possible answers.
// Uses DataBaseHelper class
void getInfoFromDatabase(int categoryId, int questionId) {
DataBaseHelper myDbHelper = new DataBaseHelper(
this.getApplicationContext());
myDbHelper = new DataBaseHelper(this);
try {
myDbHelper.createDataBase();
} catch (IOException ioe) {
throw new Error("Unable to create database");
}
try {
myDbHelper.openDataBase();
questionFromDatabase = myDbHelper.getQuestion(categoryId,
questionId);
displayedQuestionFromDatabase = questionFromDatabase;
System.out
.println("questionFromDatabase = " + questionFromDatabase);
answer1FromDatabase = myDbHelper.getCorrectAnswer(categoryId,
questionId); // correct answer from database
System.out.println("correct answer from db = "
+ answer1FromDatabase);
answer2FromDatabase = myDbHelper.getWrongAnswer1(categoryId,
questionId);
answer3FromDatabase = myDbHelper.getWrongAnswer2(categoryId,
questionId);
answer4FromDatabase = myDbHelper.getWrongAnswer3(categoryId,
questionId);
myDbHelper.close();
} catch (SQLException sqle) {
System.out.println("Errored out");
try {
throw sqle;
} catch (SQLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}
// If the player selects the right answer this method is called to increase
// the score by 10 points
void increaseScore() {
currentScore = currentScore + 10;
com.triviagame.Trivia_Game.finalScore = currentScore;
}
// If the player selects the wrong answer this method is called to decrease
// the score by 10 points
void decreaseScore() {
currentScore = currentScore - 10;
// score can't go below 0
if (currentScore < 0) {
currentScore = 0;
}
com.triviagame.Trivia_Game.finalScore = currentScore;
}
// Displays the current scores on the activity
void displayScore() {
TextView yourScore = (TextView) findViewById(R.id.yourscore);
String currentScoreText;
currentScoreText = Integer.toString(currentScore);
yourScore.setText(currentScoreText);
}
void resetTimer() {
if (mCountDown != null) {
mCountDown.cancel();
}
final TextView myCounter = (TextView) findViewById(R.id.tv);
mCountDown = new CountDownTimer(21000, 1000) {
@Override
public void onFinish() {
questionCheck();
resetTimer();
}
@Override
public void onTick(long millisUntilFinished) {
myCounter.setText("Time left: "
+ String.valueOf(millisUntilFinished / 1000));
}
}.start();
}
void cancelTimer() {
if (mCountDown != null) {
mCountDown.cancel();
}
}
void questionCheck() {
if (nextOrFinishValue == 1) {
Intent e = new Intent(this, finalscore.class);
startActivity(e);
cancelTimer();
}
if (nextOrFinishValue == 0) { // If 10 questions have not been displayed
// yet, display the next question
gatherInfoBeforePopulating();
displayScore();
populateWithQuestionInfo(displayedQuestionFromDatabase,
displayedAnswer1FromDatabase, displayedAnswer2FromDatabase,
displayedAnswer3FromDatabase, displayedAnswer4FromDatabase,
nextOrFinishValue);
}
}
// gathers question and answers from database
void gatherInfoBeforePopulating() {
categoryId = Trivia_Game.getCategoryIdInMainMenu();
// Loop until a valid questionId that hasn't been used is obtained
while (validQuestionNumber == false) {
randomValue0to29 = RandomGenerator0To29();
System.out.println("random30 in onClick = " + randomValue0to29);
alreadyDisplayQuestion = questionsAlreadyDisplayed(randomValue0to29);
if (alreadyDisplayQuestion == true) {
System.out
.println("question number already displayed looking for a non displayed question");
}
if (alreadyDisplayQuestion == false) {
System.out.println("question not displayed yet");
validQuestionNumber = true;
}
}
validQuestionNumber = false;
alreadyDisplayQuestion = false;
questionId = randomValue0to29; // sets the valid random generated number
// to the questionID
// connect to database to gather the question and answers
getInfoFromDatabase(categoryId, questionId);
// Calls random number from 0 to 3 to determine which button will
// display the correct answer
randomValueZeroToThree = RandomGeneratorZeroToThree();
System.out.println("random4 in onClick = " + randomValueZeroToThree);
// Sets the order according to the button that is to display the correct
// answer
switch (randomValueZeroToThree) {
case 0:
displayedAnswer1FromDatabase = answer1FromDatabase; // correct
// answer
displayedAnswer2FromDatabase = answer2FromDatabase;
displayedAnswer3FromDatabase = answer3FromDatabase;
displayedAnswer4FromDatabase = answer4FromDatabase;
rightButton1 = true;
rightButton2 = false;
rightButton3 = false;
rightButton4 = false;
break;
case 1:
displayedAnswer2FromDatabase = answer1FromDatabase; // correct
// answer
displayedAnswer1FromDatabase = answer2FromDatabase;
displayedAnswer3FromDatabase = answer3FromDatabase;
displayedAnswer4FromDatabase = answer4FromDatabase;
rightButton1 = false;
rightButton2 = true;
rightButton3 = false;
rightButton4 = false;
break;
case 2:
displayedAnswer3FromDatabase = answer1FromDatabase; // correct
// answer
displayedAnswer1FromDatabase = answer2FromDatabase;
displayedAnswer2FromDatabase = answer3FromDatabase;
displayedAnswer4FromDatabase = answer4FromDatabase;
rightButton1 = false;
rightButton2 = false;
rightButton3 = true;
rightButton4 = false;
break;
case 3:
displayedAnswer4FromDatabase = answer1FromDatabase; // correct
// answer
displayedAnswer1FromDatabase = answer2FromDatabase;
displayedAnswer3FromDatabase = answer3FromDatabase;
displayedAnswer2FromDatabase = answer4FromDatabase;
rightButton1 = false;
rightButton2 = false;
rightButton3 = false;
rightButton4 = true;
break;
default:
displayedAnswer1FromDatabase = answer4FromDatabase; // no correct
// answer
displayedAnswer2FromDatabase = answer2FromDatabase;
displayedAnswer3FromDatabase = answer3FromDatabase;
displayedAnswer4FromDatabase = answer1FromDatabase;
rightButton1 = false;
rightButton2 = false;
rightButton3 = false;
rightButton4 = false;
}
// After the 9th question is displayed, the nextOfFinishValue should be
// set to 1 so the button displayes Finish instead of Next
if (numberOfQuestionsDisplayedCounter < 9) {
nextOrFinishValue = 0;
} else {
nextOrFinishValue = 1;
}
}
// Listeners for the 4 buttons with answers and the Next or Finish buttons
public void onClick(View v) {
switch (v.getId()) {
case R.id.answer1button:
if (rightButton1 == true) {
increaseScore();
resetTimer();
// put here to change color of button
} else {
decreaseScore();
resetTimer();
// change button to red
}
questionCheck();
break;
case R.id.answer2button:
if (rightButton2 == true) {
increaseScore();
resetTimer();
} else {
decreaseScore();
resetTimer();
}
questionCheck();
break;
case R.id.answer3button:
if (rightButton3 == true) {
increaseScore();
resetTimer();
} else {
decreaseScore();
resetTimer();
}
questionCheck();
break;
case R.id.answer4button:
if (rightButton4 == true) {
increaseScore();
resetTimer();
} else {
decreaseScore();
resetTimer();
}
questionCheck();
break;
}
}
@Override
protected void onResume() {
super.onResume();
music.play(this, R.raw.musicbackground); // play background music
}
@Override
protected void onPause() {
super.onPause();
music.stop(this); // stop playing background music
}
}
答案 0 :(得分：5)
mCountdown永远不会为空，因此请更改代码
void cancelTimer() {
if (mCountDown != null) {
mCountDown.cancel();
}
}
到
void cancelTimer() {
mCountDown.cancel();
}