react-native-view-shot/README.md

react-native-view-shot

Snapshot a view and save to an image.

The image will be stored in a temporary file that will only exist for as long as the app is running.

Getting started

npm install --save react-native-view-shot

Mostly automatic installation

react-native link react-native-view-shot

Manual installation

iOS

1. In XCode, in the project navigator, right click Libraries ➜ Add Files to [your project's name]
2. Go to node_modules ➜ react-native-view-shot and add RNViewShot.xcodeproj
3. In XCode, in the project navigator, select your project. Add libRNViewShot.a to your project’s Build Phases ➜ Link Binary With Libraries
4. Run your project (Cmd+R)<

Android

1. Open up android/app/src/main/java/[...]/MainActivity.java
   • Add import com.reactlibrary.RNViewShotPackage; to the imports at the top of the file
   • Add new RNViewShotPackage() to the list returned by the getPackages() method
2. Append the following lines to android/settings.gradle: include ':react-native-view-shot' project(':react-native-view-shot').projectDir = new File(rootProject.projectDir, '../node_modules/react-native-view-shot/android')
3. Insert the following lines inside the dependencies block in android/app/build.gradle: compile project(':react-native-view-shot')

Windows

No support yet. Feel free to PR.

Usage

import { findNodeHandle } from "react-native";
import RNViewShot from "react-native-view-shot";

RNViewShot.takeSnapshot(findNodeHandle(aRef), {
  format: "jpeg",
  quality: 0.8
})
.then(
  uri => console.log("Image saved to", uri),
  error => console.error("Oops, snapshot failed", error)
);

Example

Checkout react-native-view-shot-example

Full API

RNViewShot.takeSnapshot(view, options)

Returns a Promise of the image URI.

• view references to a React Native component.
• options may include:
  • width / height (number): the width and height of the image to capture.
  • format (string): either png or jpg/jpeg or webm (Android). Defaults to png.
  • quality (number): the quality. 0.0 - 1.0 (default). (only available on lossy formats like jpeg)

Notes

Snapshots are not guaranteed to be pixel perfect. It also depends on the platform. Here is some difference we have noticed and how to workaround.

• Support of special components like Video / GL views remains untested.
• It’s preferable to use a background color on the view you rasterize to avoid transparent pixels and potential weirdness that some border appear around texts.

Thanks

• To initial iOS work done by @jsierles in https://github.com/jsierles/react-native-view-snapshot
• To React Native implementation of takeSnapshot in iOS by @nicklockwood