我正在进行Android测验，并希望在我的每个问答页面上都有计时器。我在测验和播放按钮中有菜单页面以开始游戏。我希望这个计时器在我点击播放按钮时被触发。为此，我必须创建代表我的菜单页面的问题XML TextView。并在QuestionActivity类中实现，代表我的第一个问题页面。我也发布了WelcomeActivity类，尽管它在这个问题上没有任何作用。
播放按钮布局
<Button
android:text="Play"
android:id="@+id/playBtn"
android:layout_width="80dip"
android:layout_alignParentRight="true"
android:layout_height="wrap_content"
android:paddingTop="5dip"
android:paddingBottom="5dip"
android:textColor="#ffffff"
android:background="@drawable/start_button" />
询问代表TextView for Timer的XML
<TextView
android:id="@+id/textView1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_above="@+id/question"
android:layout_centerHorizontal="true"
android:background="@drawable/timer_bttn"
android:onClick="onClick"/>
QuestionActivity我实现了计时器代码
public class QuestionActivity extends Activity implements OnClickListener{
private Question currentQ;
private GamePlay currentGame;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.question);
/**
* Configure current game and get question
*/
currentGame = ((CYKApplication)getApplication()).getCurrentGame();
currentQ = currentGame.getNextQuestion();
Button nextBtn1 = (Button) findViewById(R.id.answer1);
nextBtn1.setOnClickListener(this);
Button nextBtn2 = (Button) findViewById(R.id.answer2);
nextBtn2.setOnClickListener(this);
Button nextBtn3 = (Button) findViewById(R.id.answer3);
nextBtn3.setOnClickListener(this);
Button nextBtn4 = (Button) findViewById(R.id.answer4);
nextBtn4.setOnClickListener(this);
/**
* Update the question and answer options..
*/
setQuestions();
}
/**
* Method to set the text for the question and answers from the current games
* current question
*/
private void setQuestions() {
//set the question text from current question
String question = Utility.capitalise(currentQ.getQuestion());
TextView qText = (TextView) findViewById(R.id.question);
qText.setText(question);
//set the available options
List<String> answers = currentQ.getQuestionOptions();
TextView option1 = (TextView) findViewById(R.id.answer1);
option1.setText(Utility.capitalise(answers.get(0)));
TextView option2 = (TextView) findViewById(R.id.answer2);
option2.setText(Utility.capitalise(answers.get(1)));
TextView option3 = (TextView) findViewById(R.id.answer3);
option3.setText(Utility.capitalise(answers.get(2)));
TextView option4 = (TextView) findViewById(R.id.answer4);
option4.setText(Utility.capitalise(answers.get(3)));
int score = currentGame.getScore();
String scr = String.valueOf(score);
TextView score1=(TextView) findViewById(R.id.score);
score1.setText(scr);
}
@Override
public void onClick(View arg0) {
//Log.d("Questions", "Moving to next question");
if(!checkAnswer(arg0)) return;
/**
* check if end of game
*/
if (currentGame.isGameOver()) {
//Log.d("Questions", "End of game! lets add up the scores..");
//Log.d("Questions", "Questions Correct: " + currentGame.getRight());
//Log.d("Questions", "Questions Wrong: " + currentGame.getWrong());
Intent i = new Intent(this, EndgameActivity.class);
startActivity(i);
finish();
}
else {
Intent i = new Intent(this, QuestionActivity.class);
startActivity(i);
finish();
}
}
@Override
public boolean onKeyDown(int keyCode, KeyEvent event) {
switch (keyCode)
{
case KeyEvent.KEYCODE_BACK :
return true;
}
return super.onKeyDown(keyCode, event);
}
/**
* Check if a checkbox has been selected, and if it
* has then check if its correct and update gamescore
*/
private boolean checkAnswer(View v) {
Button b=(Button) v;
String answer = b.getText().toString();
//Log.d("Questions", "Valid Checkbox selection made - check if correct");
if (currentQ.getAnswer().equalsIgnoreCase(answer))
{
//Log.d("Questions", "Correct Answer!");
currentGame.incrementScore();
}
else {
//Log.d("Questions", "Incorrect Answer!");
currentGame.decrementScore();
}
return true;
}
public void setTimer() {
long finishTime = 5;
CountDownTimer counterTimer = new CountDownTimer(finishTime * 1000, 1000) {
public void onFinish() {
//code to execute when time finished
}
public void onTick(long millisUntilFinished) {
int seconds = (int) (millisUntilFinished / 1000);
int minutes = seconds / 60;
seconds = seconds % 60;
if (seconds < 10) {
txtTimer.setText("" + minutes + ":0" + seconds);
} else {
txtTimer.setText("" + minutes + ":" + seconds);
}
}
};
counterTimer.start();
}
}
WelcomeActivity
public class WelcomeActivity extends Activity implements OnClickListener{
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.welcome);
//////////////////////////////////////////////////////////////////////
//////// GAME MENU /////////////////////////////////////////////////
Button playBtn = (Button) findViewById(R.id.playBtn);
playBtn.setOnClickListener(this);
Button settingsBtn = (Button) findViewById(R.id.settingsBtn);
settingsBtn.setOnClickListener(this);
Button rulesBtn = (Button) findViewById(R.id.rulesBtn);
rulesBtn.setOnClickListener(this);
Button exitBtn = (Button) findViewById(R.id.exitBtn);
exitBtn.setOnClickListener(this);
}
/**
* Listener for game menu
*/
@Override
public void onClick(View v) {
Intent i;
switch (v.getId()){
case R.id.playBtn :
//once logged in, load the main page
//Log.d("LOGIN", "User has started the game");
//Get Question set //
List<Question> questions = getQuestionSetFromDb();
//Initialise Game with retrieved question set ///
GamePlay c = new GamePlay();
c.setQuestions(questions);
c.setNumRounds(getNumQuestions());
((CYKApplication)getApplication()).setCurrentGame(c);
//Start Game Now.. //
i = new Intent(this, QuestionActivity.class);
startActivityForResult(i, Constants.PLAYBUTTON);
break;
case R.id.rulesBtn :
i = new Intent(this, RulesActivity.class);
startActivityForResult(i, Constants.RULESBUTTON);
break;
case R.id.settingsBtn :
i = new Intent(this, SettingsActivity.class);
startActivityForResult(i, Constants.SETTINGSBUTTON);
break;
case R.id.exitBtn :
finish();
break;
}
}
答案 0 :(得分：0)
正如Piyush Gupta所述，您应该在setTimer()的{{1}}中调用onResume方法。
来自Android Developer Documentation：
QuestionActivity
在您的代码中，您还应该在(onResume is) called for your activity to start interacting with the user. This is a good place to begin animations, open exclusive-access devices (such as the camera), etc. 类成员中使用counterTimer，而不是局部变量;如果不这样做，setTimer()电话完成后，它将超出范围，您对它的访问将会丢失。
因此，您需要将以下内容添加到setTimer()：
QuestionActivity以上示例使用您现在的代码，但我建议您使用类成员在public class QuestionActivity extends Activity implements OnClickListener{
// NEW: add counterTimer as a member
private CountDownTimer counterTimer;
// NEW: implement onResume
@Override
public void onResume() {
setTimer();
super.onResume();
}
// CHANGE: setTimer should be changed as follows
public void setTimer() {
long finishTime = 5;
// NOTE: use the member, instead of a local
counterTimer = new CountDownTimer(finishTime * 1000, 1000) {
public void onFinish() {
//code to execute when time finished
}
public void onTick(long millisUntilFinished) {
int seconds = (int) (millisUntilFinished / 1000);
int minutes = seconds / 60;
seconds = seconds % 60;
if (seconds < 10) {
txtTimer.setText("" + minutes + ":0" + seconds);
} else {
txtTimer.setText("" + minutes + ":" + seconds);
}
}
};
counterTimer.start();
}
}
中创建计时器来存储它（即当前在setTimer（）中的所有内容，除了onCreate调用。然后在counterTimer.start();中使用counterTimer.start();。并且可以向onResume添加counterTimer.cancel()调用，以便在活动失去焦点时计时器结束。