npm install react-native-view-shot
react-native link react-native-view-shot

import { captureScreen } from "react-native-view-shot";
captureScreen({
 format: "jpg",
 quality: 0.8
})
.then(
 uri => console.log("Image saved to", uri),
 error => console.error("Oops, snapshot failed", error)
);

import { captureRef } from "react-native-view-shot";
render() {
   return (
 <ScrollView ref="full">
  <View ref="form1”>
   </View>
         <View ref="form2”>
   </View>
 </ScrollView>
);
}
snapshot = refname => () =>
captureRef(refname, {
 format: "jpg",
 quality: 0.8,
 result: "tmpfile",
 snapshotContentContainer: true
})
.then(
 uri => console.log("Image saved to", uri),
 error => console.error("Oops, snapshot failed", error)
);