# fling

**Repository Path**: changleibox/fling

## Basic Information

- **Project Name**: fling
- **Description**: No description available
- **Primary Language**: Dart
- **License**: MIT
- **Default Branch**: master
- **Homepage**: None
- **GVP Project**: No

## Statistics

- **Stars**: 0
- **Forks**: 0
- **Created**: 2022-02-27
- **Last Updated**: 2023-06-09

## Categories & Tags

**Categories**: Uncategorized

**Tags**: Flutter

## README

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模拟系统`Hero`实现的购物车抛物线动画

## Features

轻松实现购物车抛物线动画

## Getting started

```ymal
fling:
  git: https://github.com/changleibox/fling.git
```

## Usage

实现抛物线动画`flightShuttleBuilder`. 

```dart
FlightShuttleTransition(
  fromFlingContext: fromFlingContext,
  toFlingContext: toFlingContext,
  fromFlingLocation: fromFlingLocation,
  toFlingLocation: toFlingLocation,
  factor: animation,
  interpolator: (end, t) {
    // 二阶贝塞尔曲线
    final Offset control;
    if (end.dx == 0 || end.dy == 0) {
      control = Offset.zero;
    } else if (end.dy < 0) {
      control = Offset(0, end.dy);
    } else {
      control = Offset(end.dx, 0);
    }
    return control * 2 * t * (1 - t) + end * math.pow(t, 2).toDouble();
  },
  builder: (context, bounds, edgeValue, middleValue, fling) {
    final child = (fling.child as _ContextBuilder).child as _ColorBlock;
    return _ColorBlock.fromSize(
      size: Size.lerp(_flightShuttleSize, bounds.size, edgeValue),
      color: Color.lerp(_flightShuttleColor, child.color, edgeValue),
      radius: Radius.lerp(_flightShuttleRadius, child.radius, edgeValue),
      child: edgeValue == 0 ? _flightShuttleChild : child.child,
    );
  },
);
```

完整demo详见：https://github.com/changleibox/flutter_demo.git/