omnAPP/lib/app/widgets/kr_simple_loading.dart

import 'package:flutter/material.dart';

/// 简单的加载动画组件，替代有问题的flutter_spinkit
class KRSimpleLoading extends StatefulWidget {
  final Color? color;
  final double size;
  final Duration duration;

  const KRSimpleLoading({
    super.key,
    this.color,
    this.size = 40.0,
    this.duration = const Duration(milliseconds: 1000),
  });

  @override
  State<KRSimpleLoading> createState() => _KRSimpleLoadingState();
}

class _KRSimpleLoadingState extends State<KRSimpleLoading>
    with SingleTickerProviderStateMixin {
  late AnimationController _controller;
  late Animation<double> _animation;

  @override
  void initState() {
    super.initState();
    _controller = AnimationController(
      duration: widget.duration,
      vsync: this,
    );
    _animation = Tween<double>(
      begin: 0.0,
      end: 1.0,
    ).animate(CurvedAnimation(
      parent: _controller,
      curve: Curves.easeInOut,
    ));
    _controller.repeat();
  }

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

  @override
  Widget build(BuildContext context) {
    return AnimatedBuilder(
      animation: _animation,
      builder: (context, child) {
        return Transform.rotate(
          angle: _animation.value * 2 * 3.14159,
          child: Container(
            width: widget.size,
            height: widget.size,
            decoration: BoxDecoration(
              shape: BoxShape.circle,
              border: Border.all(
                color: widget.color ?? Theme.of(context).primaryColor,
                width: 2.0,
              ),
            ),
            child: Padding(
              padding: const EdgeInsets.all(2.0),
              child: CircularProgressIndicator(
                strokeWidth: 2.0,
                valueColor: AlwaysStoppedAnimation<Color>(
                  widget.color ?? Theme.of(context).primaryColor,
                ),
              ),
            ),
          ),
        );
      },
    );
  }
}

/// 脉冲加载动画
class KRSimplePulse extends StatefulWidget {
  final Color? color;
  final double size;
  final Duration duration;

  const KRSimplePulse({
    super.key,
    this.color,
    this.size = 40.0,
    this.duration = const Duration(milliseconds: 1500),
  });

  @override
  State<KRSimplePulse> createState() => _KRSimplePulseState();
}

class _KRSimplePulseState extends State<KRSimplePulse>
    with SingleTickerProviderStateMixin {
  late AnimationController _controller;
  late Animation<double> _animation;

  @override
  void initState() {
    super.initState();
    _controller = AnimationController(
      duration: widget.duration,
      vsync: this,
    );
    _animation = Tween<double>(
      begin: 0.0,
      end: 1.0,
    ).animate(CurvedAnimation(
      parent: _controller,
      curve: Curves.easeInOut,
    ));
    _controller.repeat();
  }

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

  @override
  Widget build(BuildContext context) {
    return AnimatedBuilder(
      animation: _animation,
      builder: (context, child) {
        return Transform.scale(
          scale: 0.5 + (_animation.value * 0.5),
          child: Opacity(
            opacity: 1.0 - _animation.value,
            child: Container(
              width: widget.size,
              height: widget.size,
              decoration: BoxDecoration(
                shape: BoxShape.circle,
                color: widget.color ?? Theme.of(context).primaryColor,
              ),
            ),
          ),
        );
      },
    );
  }
}

/// 波浪加载动画
class KRSimpleWave extends StatefulWidget {
  final Color? color;
  final double size;
  final Duration duration;

  const KRSimpleWave({
    super.key,
    this.color,
    this.size = 40.0,
    this.duration = const Duration(milliseconds: 1200),
  });

  @override
  State<KRSimpleWave> createState() => _KRSimpleWaveState();
}

class _KRSimpleWaveState extends State<KRSimpleWave>
    with TickerProviderStateMixin {
  late List<AnimationController> _controllers;
  late List<Animation<double>> _animations;

  @override
  void initState() {
    super.initState();
    _controllers = List.generate(3, (index) {
      return AnimationController(
        duration: widget.duration,
        vsync: this,
      );
    });
    
    _animations = _controllers.map((controller) {
      return Tween<double>(
        begin: 0.0,
        end: 1.0,
      ).animate(CurvedAnimation(
        parent: controller,
        curve: Curves.easeInOut,
      ));
    }).toList();

    for (int i = 0; i < _controllers.length; i++) {
      Future.delayed(Duration(milliseconds: i * 200), () {
        if (mounted) {
          _controllers[i].repeat();
        }
      });
    }
  }

  @override
  void dispose() {
    for (var controller in _controllers) {
      controller.dispose();
    }
    super.dispose();
  }

  @override
  Widget build(BuildContext context) {
    return Row(
      mainAxisSize: MainAxisSize.min,
      children: List.generate(3, (index) {
        return AnimatedBuilder(
          animation: _animations[index],
          builder: (context, child) {
            return Container(
              margin: const EdgeInsets.symmetric(horizontal: 2.0),
              width: widget.size / 6,
              height: widget.size * (0.3 + (_animations[index].value * 0.7)),
              decoration: BoxDecoration(
                color: widget.color ?? Theme.of(context).primaryColor,
                borderRadius: BorderRadius.circular(2.0),
              ),
            );
          },
        );
      }),
    );
  }
}