React-native-fs: undefined is not an object (evaluating 'RNFSManager.RNFSFileTypeRegular')

[925941723]

I got this error in RN 0.49:undefined is not an object (evaluating 'RNFSManager.RNFSFileTypeRegular')

I have tried:
npm install react-native-fs --save
react-native link react-native-fs
and delete ios/build,delete node_moudles,delete app and rebuild again.
But not work.

I just used by a simple code:
var RNFS = require('react-native-fs');

I only run on IOS,and terminal show:
rnpm-install info Android module react-native-fs is already linked
rnpm-install info iOS module react-native-fs is already linked

I have no idea to solve, anyone can help me?

[925941723]

It work by Adding Manually in XCode,thanks