How to wait for action of user in Flutter? - flutter

Question

I have a problem with a function. I need to realize a func which will be work correctly when user taps on button. I need to froze this func and wait for user's action. (tap on button).
Maybe y have already to faced to the same prob
void submitAnswer(String submittedAnswer) async {
timerAnimationController.stop();
if (!context.read<QuestionsCubit>().questions()[currentQuestionIndex].attempted) {
context.read<QuestionsCubit>().updateQuestionWithAnswerAndLifeline(context.read<QuestionsCubit>().questions()[currentQuestionIndex].id, submittedAnswer);
updateTotalSecondsToCompleteQuiz();
//change question
await Future.delayed(Duration(seconds: inBetweenQuestionTimeInSeconds));
if (currentQuestionIndex != (context.read<QuestionsCubit>().questions().length - 1)) {
updateSubmittedAnswerForBookmark(context.read<QuestionsCubit>().questions()[currentQuestionIndex]);
timerAnimationController.stop();
//I want to froze this part and wait for user's action.
//When user taps on 'next', it continues working.
//////////////////////////////////////////////////////
changeQuestion();
if (widget.quizType == QuizTypes.audioQuestions) {
timerAnimationController.value = 0.0;
showOptionAnimationController.forward();
} else {
timerAnimationController.forward(from: 0.0);
}
//////////////////////////////////////////////////////
} else {
updateSubmittedAnswerForBookmark(context.read<QuestionsCubit>().questions()[currentQuestionIndex]);
navigateToResultScreen();
}
}
}
When user taps on button, this func continue working
TextButton(
child: Text("Next >>"),
onPressed: () {
setState(() {
callMyFun();
});
//global.setMyStatus == true;
}
)

Answer 1

Disclaimer: while this will solve your problem, it's far away from
good practice, you should split your function into two
different ones
You can achieve that using Completer
Example:
Completer<void>? nextButtonCompleter;
Future<void> submitAnswer(String submittedAnswer) async {
// Your code (removed to make answer short)
// ...
//I want to froze this part and wait for user's action.
//When user taps on 'next', it continues working.
final completer = new Completer<void>();
nextButtonCompleter = completer;
// This line will wait until onPressed called
await completer.future;
// your other code
}
And in your button
TextButton(
child: Text("Next >>"),
onPressed: () {
setState(() {
callMyFun();
});
nextButtonCompleter?.complete();
nextButtonCompleter = null;
}
)