Flutter 用自定义转场动画实现页面切换

RouteTransitionsBuilder _standardTransitionsBuilder(
      TransitionType? transitionType) {
    return (BuildContext context, Animation<double> animation,
        Animation<double> secondaryAnimation, Widget child) {
      if (transitionType == TransitionType.fadeIn) {
        return FadeTransition(opacity: animation, child: child);
      } else {
        const Offset topLeft = const Offset(0.0, 0.0);
        const Offset topRight = const Offset(1.0, 0.0);
        const Offset bottomLeft = const Offset(0.0, 1.0);

        Offset startOffset = bottomLeft;
        Offset endOffset = topLeft;
        if (transitionType == TransitionType.inFromLeft) {
          startOffset = const Offset(-1.0, 0.0);
          endOffset = topLeft;
        } else if (transitionType == TransitionType.inFromRight) {
          startOffset = topRight;
          endOffset = topLeft;
        } else if (transitionType == TransitionType.inFromBottom) {
          startOffset = bottomLeft;
          endOffset = topLeft;
        } else if (transitionType == TransitionType.inFromTop) {
          startOffset = Offset(0.0, -1.0);
          endOffset = topLeft;
        }

        return SlideTransition(
          position: Tween<Offset>(
            begin: startOffset,
            end: endOffset,
          ).animate(animation),
          child: child,
        );
      }
    };
  }

const RotationTransition({
    Key? key,
    required Animation<double> turns,
    this.alignment = Alignment.center,
    this.child,
  })  : assert(turns != null),
        super(key: key, listenable: turns);

//逆时针围绕中心旋转
RouterManager.router.navigateTo(
  context,
  RouterManager.transitionPath,
  transition: TransitionType.custom,
  transitionBuilder:
      (context, animation, secondaryAnimation, child) {
    return RotationTransition(
      turns: Tween<double>(
        begin: 0.25,
        end: 0.0,
      ).animate(animation),
      child: child,
    );
  },
);

//...
//顺时针围绕左下角旋转
RouterManager.router.navigateTo(
  context,
  RouterManager.transitionPath,
  transition: TransitionType.custom,
  transitionBuilder:
      (context, animation, secondaryAnimation, child) {
    return RotationTransition(
      alignment: Alignment.bottomLeft,
      turns: Tween<double>(
        begin: -0.25,
        end: 0.0,
      ).animate(animation),
      child: child,
    );
  },
);

RouterManager.router.navigateTo(
  context,
  RouterManager.transitionPath,
  transition: TransitionType.custom,
  transitionBuilder:
      (context, animation, secondaryAnimation, child) {
    return ScaleTransition(
      scale: Tween<double>(
        begin: 0.5,
        end: 1.0,
      ).animate(animation),
      child: child,
    );
  },
);

class SkewTransition extends AnimatedWidget {
  const SkewTransition({
    Key key,
    Animation<double> turns,
    this.alignment = Alignment.center,
    this.child,
  })  : assert(turns != null),
        super(key: key, listenable: turns);

  Animation<double> get turns => listenable as Animation<double>;

  final Alignment alignment;

  final Widget child;

  @override
  Widget build(BuildContext context) {
    final double turnsValue = turns.value;
    final Matrix4 transform =
        Matrix4.skew(turnsValue * pi * 2.0, turnsValue * pi * 2.0);
    return Transform(
      transform: transform,
      alignment: alignment,
      child: child,
    );
  }
}

RouterManager.router.navigateTo(
  context,
  RouterManager.transitionPath,
  transition: TransitionType.custom,
  transitionBuilder:
      (context, animation, secondaryAnimation, child) {
    return SkewTransition(
      turns: Tween<double>(
        begin: -0.05,
        end: 0.0,
      ).animate(animation),
      child: child,
    );
  },
);