react-native-yet-another-sortable/README.md

Drag-and-drop sortable scrollable grid view for React Native.

# react-native-yet-another-sortable

[![Build Status](https://travis-ci.com/k5md/react-native-yet-another-sortable.svg?branch=release)](https://travis-ci.com/k5md/react-native-yet-another-sortable)

A sortable scrollable grid / list component for React Native.
* Change number of columns and row height on the fly
* Much better performance (especially in debug, compared to alternatives)
* Fast updates
* Controllable order
* Auto-scroll when dragged item is close to the container's border
Essentially based on react-native-sortable-grid, it has some improvements and changes, that made me publish it as a separate package instead of making a PR.

<p align="center">
  <img src="https://s7.gifyu.com/images/rnyas.gif">
</p>

## Getting Started
### Installation
```
npm install react-native-yet-another-sortable --save
```
### Usage
Check out [example project](https://github.com/k5md/react-native-yet-another-sortable/tree/master/example).
 
```javascript
import React, { useState, useCallback } from 'react';
import SortableGrid from 'react-native-yet-another-sortable';

const Example = () => {
  const [data] = useState([
    { value: 0, key: 'key0' },
    { value: 1, key: 'key1' },
    { value: 2, key: 'key2' },
  ]);

  const [order, setOrder] = useState(['key2', 'key1', 'key0']);

  const renderItem = useCallback(({ value, color }) => (
    <View style={{ flex: 1 }}>
      <Text>{value}</Text>
    </View>
  ), []);

  return (
    <View style={{ flex: 1 }}>
      <SortableGrid
        order={order}
        data={data}
        renderItem={renderItem}
        onDeactivateDrag={setOrder}
      />
    </View>
  );
};
```

### Props
| parameter  | type   | required | description |
| :--------  | :----  | :------- | :---------- |
| order | array of string keys | yes | array of data key properties used to determine entry order |
| data | array of objects with key property | yes | array of items to be passed to renderItem |
| rowHeight | number | no | row height |
| columns | number | no | number of columns per row |
| activationTreshold | number | no | time in ms required to activate drag on hold |
| transitionDuration | number | no | time in ms required to move cell to its position on release |
| renderItem | function | yes | render function for each entry, is passed a data item |

### Event props
| parameter  | type   | required | description |
| :--------  | :----  | :------- | :---------- |
| onActivateDrag | (key, grid) => void | no |  Will execute after one holds the item for activateTreshold, before onGrantBlock |
| onGrantBlock | (event, gestureState, grid) => void | no | Will execute on drag start |
| onMoveBlock | (event, gestureState, grid) => void | no |  Will execute on each move |
| onReleaseBlock | (event, gestureState, grid) => void | no |  Will execute on drag release |
| onDeactivateDrag | (order, grid) => void | no |  Will execute on active item drop, after onReleaseBlock, with new order as an argument |

### Data item props
| parameter  | type   | required | description |
| :--------  | :----  | :------- | :---------- |
| inactive | boolean | no      | Makes block not draggable |
| key | string | yes | key used to order items

## Development
In order to develop the application or build android .apk from the sources one should:
1. Clone this repository
2. Install package dependencies with `npm install`
3. Navigate to example folder: `cd example`
3. Install example project dependencies `npm install`
3. Run Metro bundler with `react-native start`
4. Connect an emulator or physical device via adb, like this (tested with [mEMU](https://www.memuplay.com/)):
	- `adb connect 127.0.0.1:21503`
	- `adb reverse tcp:8081 tcp:8081`
5. Build and watch with `react-native run-android`, changes from src directory are picked automatically because of example's metro and babel configurations.

## Contributions
PR are always welcome!

## Todos
* Better scroll-on-drag behaviour (smooth scroll without ugly timeouts and large scroll results in the dragged block trembling)
* Refactoring while perserving the performance
* Actual tests