After run pod install react get removed while upgrading react-native version - react-native

Question

Can anyone explain why the pod install removing the React. Also it shows the React missing in product-->Edit scheme.
I need any good solution
RCTBrigeModule.h file not found error?
I dont have any idea how to fix this.
Before unlinking the package and not run pod install
# Uncomment the next line to define a global platform for your project
platform :ios, '9.0'
require_relative '../node_modules/#react-native-community/cli-platform-ios/native_modules'
pod 'Fabric'
pod 'Crashlytics'
target 'App' do
# Uncomment the next line if you're using Swift or would like to use dynamic frameworks
# use_frameworks!
# Pods for App
target 'App-tvOSTests' do
inherit! :search_paths
# Pods for testing
pod 'rn-fetch-blob', :path => '../node_modules/rn-fetch-blob'
pod 'BVLinearGradient', :path => '../node_modules/react-native-linear-gradient'
pod 'RNVectorIcons', :path => '../node_modules/react-native-vector-icons'
pod 'RNImageCropPicker', :path => '../node_modules/react-native-image-crop-picker'
pod 'react-native-camera', :path => '../node_modules/react-native-camera'
pod 'RNImageRotate', :path => '../node_modules/react-native-image-rotate'
pod 'RNShare', :path => '../node_modules/react-native-share'
pod 'RNViewShot', :path => '../node_modules/react-native-view-shot'
pod 'RNFS', :path => '../node_modules/react-native-fs'
pod 'BugsnagReactNative', :path => '../node_modules/bugsnag-react-native'
pod 'RNGestureHandler', :path => '../node_modules/react-native-gesture-handler'
pod 'react-native-webview', :path => '../node_modules/react-native-webview'
end
target 'AppTests' do
inherit! :search_paths
# Pods for testing
end
end
After linking and run pod install
# Uncomment the next line to define a global platform for your project
platform :ios, '9.0'
require_relative '../node_modules/#react-native-community/cli-platform-ios/native_modules'
pod 'Fabric'
pod 'Crashlytics'
target 'App' do
# Uncomment the next line if you're using Swift or would like to use dynamic frameworks
# use_frameworks!
# Pods for App
target 'App-tvOSTests' do
inherit! :search_paths
# Pods for testing
end
target 'AppTests' do
inherit! :search_paths
# Pods for testing
end
end

Answer 1

If you trying to to upgrade to v0.60+, you have to do this manually with this tool.
(https://react-native-community.github.io/upgrade-helper/). There is many breaking changes including pod support and androidX support.
Update all libraries to latest version, remove all manual linked libraries before RN upgrade from Xcode, to avoid Xcode crashes.
This article may help https://reactnative.thenativebits.com/courses/upgrading-react-native/upgrade-to-react-native-0.60/