dreampad/lib/app/shared/widgets/swipe_next_page_container.dart

import 'package:dartx/dartx.dart';
import 'package:dreampad/app/shared/shared.dart';
import 'package:flutter/gestures.dart';
import 'package:flutter/material.dart';
import 'package:flutter_hooks/flutter_hooks.dart';

class SwipeNextPageContainer extends HookWidget {
  /// 叠放[children]
  ///
  /// [children]可用用[SwipeNextPageHandler]套[Widget]使之成为滑动的[handler]
  const SwipeNextPageContainer({
    super.key,
    required this.children,
  });

  final List<Widget> children;

  // 定义一个便捷方法，方便子树中的widget获取共享数据
  static SwipePageHandlerReceiver? of(BuildContext context) {
    return context.getInheritedWidgetOfExactType<SwipePageHandlerReceiver>();
  }

  @override
  Widget build(BuildContext context) {
    return LayoutBuilder(builder: (context, constraint) {
      final height = constraint.maxHeight;
      return HookBuilder(builder: (context) {
        final currentIndex = useState(children.length - 1);
        final controller = useAnimationController(
          lowerBound: 0,
          upperBound: height,
          duration: const Duration(milliseconds: 500),
        );
        useEffect(() {
          void onAnimationStateChanged(AnimationStatus status) {
            if (status == AnimationStatus.completed) {
              currentIndex.value = currentIndex.value - 1;
            }
          }

          controller.addStatusListener(onAnimationStateChanged);
          return () {
            controller.removeStatusListener(onAnimationStateChanged);
          };
        }, [controller]);
        useEffect(() {
          controller.value = 0;
          return null;
        }, [currentIndex.value]);
        return SwipePageHandlerReceiver(
          controller: controller,
          currentIndex: currentIndex,
          child: AnimatedBuilder(
              animation: controller,
              builder: (context, _) =>
                  Stack(
                    fit: StackFit.expand,
                    children: children.mapIndexed((index, child) {
                      final Widget result;
                      if (index > currentIndex.value) {
                        result = const Positioned(child: SizedBox.shrink());
                      } else if (index < currentIndex.value) {
                        result = Positioned.fill(child: child);
                      } else {
                        final offset = controller.value;

                        result = Positioned(
                          left: 0,
                          right: 0,
                          top: 0 - offset,
                          bottom: 0 + offset,
                          child: child,
                        );
                      }
                      return SwipePageItemState(
                        index: index,
                        child: result,
                      );
                    }).toList(),
                  )),
        );
      });
    });
  }
}

class SwipePageHandlerReceiver extends InheritedWidget {
  const SwipePageHandlerReceiver({
    super.key,
    required super.child,
    required this.controller,
    required this.currentIndex,
  });

  // 定义一个便捷方法，方便子树中的widget获取共享数据
  static SwipePageHandlerReceiver? of(BuildContext context) {
    return context.getInheritedWidgetOfExactType<SwipePageHandlerReceiver>();
  }

  final AnimationController controller;

  final ValueNotifier<int> currentIndex;

  @override
  bool updateShouldNotify(covariant InheritedWidget oldWidget) {
    return false;
  }
}

class SwipePageItemState extends InheritedWidget {
  const SwipePageItemState({
    super.key,
    required super.child,
    required this.index,
  });

  // 定义一个便捷方法，方便子树中的widget获取共享数据
  static SwipePageItemState? of(BuildContext context) {
    return context.getInheritedWidgetOfExactType();
  }

  final int index;

  @override
  bool updateShouldNotify(covariant InheritedWidget oldWidget) {
    return false;
  }
}

class SwipeNextPageHandler extends StatelessWidget {
  const SwipeNextPageHandler({
    super.key,
    required this.child,
  });

  final Widget child;

  @override
  Widget build(BuildContext context) {
    final controller = SwipePageHandlerReceiver
        .of(context)
        ?.controller;
    if (controller == null) {
      return child;
    }
    return Material(
      color: Colors.transparent,
      child: InkWell(
        onTap: () {},
        child: GestureDetector(
          behavior: HitTestBehavior.opaque,
          onPanEnd: (details) {
            var velocityY = details.velocity.pixelsPerSecond.dy;
            if (velocityY.abs() > kMinFlingVelocity) {
              if (velocityY < 0) {
                controller.animateTo(
                  controller.upperBound,
                  curve: Curves.decelerate,
                  duration: Duration(
                    milliseconds:
                    (controller.upperBound - controller.value).abs() ~/
                        (velocityY.abs() / 1000).coerceAtLeast(1),
                  ),
                );
              } else {
                controller.animateBack(
                  controller.lowerBound,
                  curve: Curves.decelerate,
                  duration: Duration(
                    milliseconds:
                    (controller.value - controller.lowerBound).abs() ~/
                        (velocityY.abs() / 1000).coerceAtLeast(1),
                  ),
                );
              }
            } else {
              if (controller.value > controller.upperBound * 2 / 3) {
                controller.forward();
              } else {
                controller.reverse();
              }
            }
          },
          onPanCancel: () {
            controller.animateTo(controller.lowerBound, curve: Curves.easeIn);
          },
          onPanUpdate: (details) {
            controller.value -= details.delta.dy;
          },
          child: child,
        ),
      ),
    );
  }
}

class SwipePageFadeOutContainer extends HookWidget {
  const SwipePageFadeOutContainer({
    super.key,
    required this.child,
  });

  final Widget child;

  @override
  Widget build(BuildContext context) {
    return AnimatedBuilder(
      animation: SwipeNextPageContainer.of(context)!.controller,
      builder: (context, _) {
        final controller = SwipeNextPageContainer.of(context)!.controller;
        return Opacity(
          opacity: 1 - controller.value / controller.upperBound,
          child: child,
        );
      },
    );
  }
}

class SwipePageCurrentVisible extends HookWidget {
  const SwipePageCurrentVisible({
    super.key,
    required this.child,
  });

  final Widget child;

  @override
  Widget build(BuildContext context) {
    final currentIndexState = SwipeNextPageContainer.of(context)!.currentIndex;
    final index = SwipePageItemState.of(context)!.index;
    final isVisible =
    useListenableSelector(
        currentIndexState, () => currentIndexState.value == index);
    return Visibility(
      visible: isVisible,
      child: AnimatedVisibilityWidget(
        animationWidgetBuilder: AnimatedVisibilityWidget.fadeAnimationWidgetBuilder,
        duration: const Duration(milliseconds: 800),
        isVisible: true,
        isInitAnimated: true,
        child: child,
      ),
    );
  }
}