felixblaschke

class BarChartApplication extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return Padding(
      padding: const EdgeInsets.all(20.0),
      child: Row(
        mainAxisAlignment: MainAxisAlignment.spaceEvenly,
        children: <Widget>[
          Bar(0.3, "2013"),
          Bar(0.5, "2014"),

felixblaschke

class Bar extends StatelessWidget {
 // ...

  @override
  Widget build(BuildContext context) {
    return ControlledAnimation(
      duration: Duration(milliseconds: (height * _baseDurationMs).round()),
      tween: Tween(begin: 0.0, end: height),
      builder: (context, animatedHeight) {
        return Column(

felixblaschke

class Bar extends StatelessWidget {
  final double height;
  final String label;

  final int _baseDurationMs = 1000;
  final double _maxElementHeight = 100;

  Bar(this.height, this.label);

  @override

felixblaschke

 var _dataIsLoaded = false;

  _loadData() {
    // Simulate HTTP Request
    _dataIsLoaded = false;
    Future.delayed(Duration(seconds: 4)).then((_) => _dataIsLoaded = true);

    controller.addTasks([
      FromToTask(
          duration: Duration(milliseconds: 700),

felixblaschke

 @override
  Widget build(BuildContext context) {
    return Column(
      mainAxisAlignment: MainAxisAlignment.start,
      crossAxisAlignment: CrossAxisAlignment.center,
      children: <Widget>[_progressIndicator(), _requestButton()],
    );
  }

  var _showCircularProgressIndicator = false;

felixblaschke

class ProgressIndicatorAnimation extends StatefulWidget {
  @override
  _ProgressIndicatorAnimationState createState() =>
      _ProgressIndicatorAnimationState();
}

class _ProgressIndicatorAnimationState extends State<ProgressIndicatorAnimation>
    with AnimationControllerMixin {
  Animation tween;

felixblaschke

    // Animate forward (1s)
    controller
        .addTask(FromToTask(duration: Duration(seconds: 1), to: 1.0));

    // Animate reverse (0,5s)
    controller
        .addTask(FromToTask(duration: Duration(milliseconds: 500), to: 0.0));

    // Clear queue (stop all running tasks) and loop forever
    controller

felixblaschke

class _WidgetWithAnimationState extends State<WidgetWithAnimation>
    with AnimationControllerMixin {
  Animation<double> width;

  @override
  void initState() {
    width = Tween(begin: 100.0, end: 200.0).animate(controller);
    controller.addTask(FromToTask(duration: Duration(seconds: 1), to: 1.0));
    super.initState();
  }

felixblaschke

class _WidgetWithAnimationState /* ... */ {
  AnimationControllerX controller; // change here
  // ...
  @override
  void initState() {
    controller = AnimationControllerX(vsync: this); // change here
    // ...
  }
  // ...
}

felixblaschke

class _WidgetWithAnimationState extends State<WidgetWithAnimation>
    with SingleTickerProviderStateMixin {
  AnimationController controller;
  Animation<double> width;

  @override
  void initState() {
    controller = AnimationController(
      vsync: this,
      duration: Duration(seconds: 1),