AlexKenbo

import 'package:flutter/material.dart';
import 'dart:math';

void main() { 
  runApp(new MaterialApp(home: PositionedTiles()));
  

}

AlexKenbo

import 'dart:async';

void main() {
  var streamController = StreamController();
  
  streamController.stream.listen(
    (data) => print('Got eem! $data'),
    onError: (err) => print('Got an error! $err'),
    onDone: () => print('Mission complete!'),
    cancelOnError: false,

AlexKenbo

import 'dart:async';

void main() {
  var controller = StreamController<num>();
  
  // Create StreamTransformer with transformer closure
  var streamTransformer = StreamTransformer<num, num>.fromHandlers(
    handleData: (num data, EventSink sink) {
      sink.add(data * 2);
    }, 

AlexKenbo

import 'dart:async';

void main() {
  var streamController = StreamController();
  
  streamController.stream.listen(print);
  //streamController.stream.listen(print); // ошибка: поток уже слушается, разкомментируйте строку, чтобы увидеть
  streamController.sink.add('Одиночная подписка: 1');
  streamController.sink.add('Одиночная подписка: 2');
  

AlexKenbo

import 'dart:async';

var stream = Stream.fromIterable([1, 2, 3, 4, 5]);

void main() {
  final controller1 = new StreamController();
  final controller2 = new StreamController();

  controller1.addStream(stream);

AlexKenbo

import 'dart:async';
Future<int> sumStream(Stream<int> stream) async {
  var sum = 0;
  await for (var value in stream) {
    sum += value;
  }
  return sum;
}

Stream<int> countStream(int to) async* {

AlexKenbo

import 'dart:async';

Future<int> sumStream(Stream<int> stream) async {
  var sum = 0;
  try {
    await for (var value in stream) {
      sum += value;
    }
  } catch (e) {
    return -1;

AlexKenbo

// asynchronous data 
main() async {
  Duration interval = Duration(seconds: 2);
  Stream<int> stream = Stream<int>.periodic(interval, callback);
  await for(int i in stream){
    print(i);
  }
}
// This callback modify the given value to even number.
int callback(int value){

AlexKenbo

// asynchronous data 
main() async {
  Duration interval = Duration(seconds: 1);
  Stream<int> stream = Stream<int>.periodic(interval,transform);
  // Added this statement
  stream = stream.take(5);
await for(int i in stream){
    print(i);
  }
}

AlexKenbo

// asynchronous data 
main() async {
  Duration interval = Duration(seconds: 1);
  Stream<int> stream = Stream<int>.periodic(interval,transform);
  // Added this statement
  stream = stream.takeWhile(condition);
  await for(int i in stream){
      print(i);
   }
}