react-native-fast-image/FastImage.js

import React, { Component } from 'react'
import {
  requireNativeComponent,
  Image,
  NativeModules,
  View,
} from 'react-native'

const resolveAssetSource = require('react-native/Libraries/Image/resolveAssetSource')

const FastImageViewNativeModule = NativeModules.FastImageView

class FastImage extends Component {
  setNativeProps(nativeProps) {
    this._root.setNativeProps(nativeProps)
  }

  render() {
    const { source, onError, onLoad, onProgress, ...props } = this.props

    // If there's no source or source uri just fallback to Image.
    if (!source || !source.uri) {
      return (
        <Image
          ref={e => (this._root = e)}
          {...props}
          source={source}
          onProgress={onProgress}
          onError={onError}
          onLoad={onLoad}
        />
      )
    }

    const resolvedSource = resolveAssetSource(source)
    return (
      <FastImageView
        ref={e => (this._root = e)}
        {...props}
        source={resolvedSource}
        onFastImageProgress={onProgress}
        onFastImageError={onError}
        onFastImageLoad={onLoad}
      />
    )
  }
}

FastImage.resizeMode = {
  contain: 'contain',
  cover: 'cover',
  stretch: 'stretch',
  center: 'center',
}

FastImage.priority = {
  low: 'low',
  normal: 'normal',
  high: 'high',
}

FastImage.preload = sources => {
  FastImageViewNativeModule.preload(sources)
}

FastImage.defaultProps = {
  resizeMode: FastImage.resizeMode.cover,
  onProgress: Function.prototype,
  onLoad: Function.prototype,
  onError: Function.prototype,
}

const FastImageView = requireNativeComponent('FastImageView', FastImage, {
  nativeOnly: {
    onFastImageProgress: true,
    onFastImageError: true,
    onFastImageLoad: true,
  },
})

export default FastImage