rotating_plain.dart

import 'dart:ui';

import 'package:flutter/material.dart';

class SpinKitRotatingPlain extends StatefulWidget {
  final Color color;
  final double size;
  final IndexedWidgetBuilder itemBuilder;
  final Duration duration;
  final AnimationController controller;

  SpinKitRotatingPlain({
    Key key,
    this.color,
    this.size = 100,
    this.itemBuilder,
    this.duration = const Duration(seconds: 2),
    this.controller,
  })  : assert(
            !(itemBuilder is IndexedWidgetBuilder && color is Color) &&
                !(itemBuilder == null && color == null),
            'You should specify either a itemBuilder or a color'),
        assert(size != null),
        super(key: key);
  @override
  _SpinKitRotatingPlainState createState() => _SpinKitRotatingPlainState();
}

class _SpinKitRotatingPlainState extends State<SpinKitRotatingPlain>
    with SingleTickerProviderStateMixin {
  AnimationController _controller;
  Animation<double> _animation1, _animation2;

  @override
  void initState() {
    super.initState();
    _controller = (widget.controller ??
        AnimationController(vsync: this, duration: widget.duration))
      ..addListener(() => setState(() {}))
      ..repeat();
    _animation1 = Tween(begin: 0.0, end: 180.0).animate(CurvedAnimation(
        parent: _controller,
        curve: const Interval(0.0, 0.5, curve: Curves.easeIn)));
    _animation2 = Tween(begin: 0.0, end: 180.0).animate(CurvedAnimation(
        parent: _controller,
        curve: const Interval(0.5, 1.0, curve: Curves.easeInOut)));
  }

  @override
  void dispose() {
    super.dispose();
    _controller.dispose();
    super.dispose();
  }

  @override
  Widget build(BuildContext context) {
    final double valorAngulo = 0.0174533;
    double sizeContainerBlur = 100;
    double sizeSigma = 2;
    return Stack(
      children: <Widget>[
        Align(
          child: Center(
            child: BackdropFilter(
              filter: ImageFilter.blur(sigmaX: sizeSigma, sigmaY: sizeSigma),
              child: Container(
                width: sizeContainerBlur,
                height: sizeContainerBlur,
                child: Container(color: Colors.black.withOpacity(0)),
              ),
            ),
          ),
        ),
        Center(
          child: Transform(
            transform: Matrix4.identity()
              ..rotateX((0 - _animation1.value) * valorAngulo)
              ..rotateY((0 - _animation2.value) * valorAngulo),
            alignment: FractionalOffset.center,
            child: SizedBox.fromSize(
                size: Size.square(widget.size),
                child: Container(
                    child: Image.asset(
                  'images/logo_google.png',
                  height: 90,
                  width: 90,
                  alignment: Alignment.center,
                ))),
          ),
        ),
      ],
    );
  }
}