iOS: Update RCTAlertManager to use new RCTAlertController

[devon94]

Summary

This should fix #29082 and #10471

Currently when an alert is being shown while a modal is being dismissed, it causes the alert not to show and In some cases it causes the UI to become unresponsive. I think this was caused by using RCTPresentedViewController to try and display the Alert the currently presented view. The View the Alert was going to be shown on is dismissed and the modal doesn't show. I implemented a new RCTAlertController to show the alert on top of the view, the modal being dismissed should now not interfere with the alert being shown.

Changelog

[iOS] [Fixed] - Fixed showing Alert while closing a Modal

Test Plan

To recreate the bug:

1. npx react-native init Test --version 0.63.0-rc.1
2. Paste the following code into App.js

/**
 * Sample React Native App
 * https://github.com/facebook/react-native
 *
 * @format
 * @flow strict-local
 */

import React from 'react';
import {
  SafeAreaView,
  StyleSheet,
  View,
  Text,
  StatusBar,
  Modal,
  Alert
} from 'react-native';

const App: () => React$Node = () => {
  const [visible, setVisible] = React.useState(false)

  const onShowModal = () => {
    setVisible(true)
  }

  onCloseBroken = () => {
    setVisible(false)
    Alert.alert('Alert', 'Alert won\'t show')
  }

  onCloseWorking = () => {
    setVisible(false)
    setTimeout(() => Alert.alert('Alert', 'Works fine'), 10)
  }

  return (
    <>
      <StatusBar barStyle="dark-content" />
      <SafeAreaView style={styles.container}>
        <Text onPress={onShowModal}>Show modal</Text>
      </SafeAreaView>
      <Modal animationType="fade" visible={visible} onRequestClose={onCloseWorking} >
        <View style={styles.container}>
          <Text onPress={onCloseBroken}>Close modal immediately</Text>
          <Text onPress={onCloseWorking}>Close modal with delay</Text>
        </View>
      </Modal>
    </>
  )
}

const styles = StyleSheet.create({
  container: {
    flex: 1,
    alignItems: 'center',
    justifyContent: 'space-around',
  },
})

export default App

3. cd Test && npx react-native run-ios
4. Show the modal and click the Close modal immediately button

The first button doesn't show the alert, the second does because it gets rendered after the modal view is dismissed. After this commit, the alert always shows on top of every view properly. You can test by pointing the react native package to my branch by modifying the package json file like this

    "react-native": "https://github.com/devon94/react-native.git#fix-ios-modal"

I was unable to reproduce the case where it causes the UI to be responsive in the test app but was able to reproduce it in our react native app at work. I can provide a video later if needed but the code is too complex to simplify into a test case.

[analysis-bot]

Platform	Engine	Arch	Size (bytes)	Diff
ios	-	universal	n/a	--

Base commit: 08d7b54

[analysis-bot]

Platform	Engine	Arch	Size (bytes)	Diff
android	hermes	arm64-v8a	6,763,624	-5,383
android	hermes	armeabi-v7a	6,426,579	-9,028
android	hermes	x86	7,151,253	-5,725
android	hermes	x86_64	7,041,184	-5,529
android	jsc	arm64-v8a	8,935,566	-3,470
android	jsc	armeabi-v7a	8,590,927	-7,122
android	jsc	x86	8,766,341	-3,789
android	jsc	x86_64	9,341,891	-3,607

Base commit: 08d7b54

[PeteTheHeat]

Nice fix!

[facebook-github-bot]

@PeteTheHeat has imported this pull request. If you are a Facebook employee, you can view this diff on Phabricator.

[PeteTheHeat]

@devon94 One question: Should this be the key window size?

The scenario I'm thinking about is iPad split screen. I think this would return the entire device screen size instead of the app's window.

[devon94]

Ah yea, you're right! I didn't think about iPad/split screen when looking at this issue. The keyWindow bounds should fix that scenario. I can add that later today

[react-native-bot]

This pull request was successfully merged by @devon94 in f319ff3.

^{When will my fix make it into a release? | Upcoming Releases}