react-native-svg-asset-plugin

    0.5.0 • Public • Published

    react-native-svg-asset-plugin

    Build Status

    Asset plugin for React Native which enables using SVGs with Image components. Works by generating PNGs during compile time, and passing them to the metro transformer.

    📱 If you also want to use SVG images for your application launcher icons, you might want to check out react-native-svg-app-icon.

    Installation

    npm

    npm install --save-dev react-native-svg-asset-plugin

    No dependencies outside of NPM. Uses sharp for SVG rasterization.

    Requires React Native version 0.57 or later to work. Expo not supported, instead you might want to use react-native-svg-transformer.

    metro

    Add 'react-native-svg-asset-plugin' to the list of assetPlugins in your metro.config.js file under the transformer section.

    For example;

    module.exports = {
      transformer: {
        getTransformOptions: async () => ({
          transform: {
            experimentalImportSupport: false,
            inlineRequires: false,
          },
        }),
        assetPlugins: ['react-native-svg-asset-plugin'],
      },
    };

    Usage

    Just require your SVG files directly into React Native Image and ImageBackground components. For example:

    <Image source={require('./assets/image.svg')} />

    Scaled PNGs will be generated under the subdirectory .png-cache alongside the SVG files, so you might want to add a .gitignore entry to exclude the cache directory from your code repo.

    Configuration

    You can configure the plugin behaviour through the optional svgAssetPlugin field in your metro.config.js file under the transformer section.

    For example;

    module.exports = {
      transformer: {
        // ...
        assetPlugins: ['react-native-svg-asset-plugin'],
        svgAssetPlugin: {
          pngCacheDir: '.png-cache',
          scales: [1, 2, 3],
          output: {
            compressionLevel: 9,
          },
        },
      },
    };

    Where the possible configuration values are:

    Field Type Default Description
    cacheDir string '.png-cache' Name of directory to store cached PNGs.
    scales number[] [1, 2, 3] PNG image scales to generate for different screen densities.
    output object {} Sharp PNG output options.
    ignoreRegex RegExp null Regex that will be matched against the source file's full path, if there's a match the file will be ignored.

    You will need to reset the bundler cache with react-native start --reset-cache for configuration changes to take effect for already generated images.

    Comparison with react-native-svg

    Most alternative ways of displaying SVG content in React Native apps are based on the react-native-svg library, which provides runtime rendering of SVG images. react-native-svg-asset-plugin works differently by rasetrizing the vector images to PNGs during compile time, and using the native image rendering APIs.

    react-native-svg react-native-svg-asset-plugin
    Rasterization Runtime Compile time
    Runtime dependencies JS + Native None
    Image compatibility No Yes
    Remote assets Yes No
    App size Smaller Larger

    Technical details

    The plugin works by intercepting loaded SVG assets, and transforming them to PNGs before they are loaded by the metro transformer. After being loaded by the transformer, they work as any other PNG file in React Native, meaning you can use and style them freely in Image components.

    Each SVG file produces three PNG files in 1x, 2x and 3x scales. The size of the PNG images are defined by the width and height attributes of the SVG images.

    SVGs are rasterized to PNGs using the sharp Node.js library, which is based on libvips C library, which includes the librsvg library that renders the SVG images.

    Install

    npm i react-native-svg-asset-plugin

    DownloadsWeekly Downloads

    932

    Version

    0.5.0

    License

    MIT

    Unpacked Size

    19.4 kB

    Total Files

    9

    Last publish

    Collaborators

    • aeirola