react-native-ui-lib/lib/components/SafeArea/SafeAreaInsetsManager.js

<p align="center"> <img src="https://user-images.githubusercontent.com/1780255/105469025-56759000-5ca0-11eb-993d-3568c1fd54f4.png" height="250px" style="display:block"/> </p> <p align="center">UI Toolset & Components Library for React Native</p> <p a

/* eslint no-underscore-dangle: 0 */
import { NativeModules, NativeEventEmitter } from 'react-native';
import _ from 'lodash';
let SafeAreaInsetsCache = null;
const NativeSafeAreaManager = NativeModules.SafeAreaManager;

class SafeAreaInsetsManager {
  _defaultInsets = {
    top: 0,
    left: 0,
    bottom: 0,
    right: 0
  };
  _safeAreaInsets = {
    top: 0,
    left: 0,
    bottom: 0,
    right: 0
  };
  _safeAreaChangedDelegates = [];

  constructor() {
    this.addSafeAreaChangedListener();
  }

  addSafeAreaChangedListener() {
    if (!NativeSafeAreaManager) {
      return;
    }

    const NativeSafeAreaEvents = new NativeEventEmitter(NativeSafeAreaManager);
    NativeSafeAreaEvents.addListener('SafeAreaInsetsDidChangeEvent', safeAreaInsets => {
      SafeAreaInsetsCache = safeAreaInsets;
      this._safeAreaInsets = SafeAreaInsetsCache;

      _.forEach(this._safeAreaChangedDelegates, delegate => {
        if (delegate.onSafeAreaInsetsDidChangeEvent) {
          delegate.onSafeAreaInsetsDidChangeEvent(this._safeAreaInsets);
        } else {
          console.warn('ERROR', 'SafeAreaInsetsManager', 'safe area changed delegate was added, but it does not implement the onSafeAreaInsetsDidChangeEvent method'); //eslint-disable-line
        }
      });
    });
  }

  async _updateInsets() {
    if (NativeSafeAreaManager && SafeAreaInsetsCache === null) {
      SafeAreaInsetsCache = await NativeSafeAreaManager.getSafeAreaInsets();
      this._safeAreaInsets = SafeAreaInsetsCache;
    }
  }

  async getSafeAreaInsets() {
    await this._updateInsets();
    return this._safeAreaInsets;
  }

  addSafeAreaChangedDelegate(delegate) {
    this._safeAreaChangedDelegates.push(delegate);
  }

  removeSafeAreaChangedDelegate(delegateToRemove) {
    _.remove(this._safeAreaChangedDelegates, currentDelegate => {
      return currentDelegate === delegateToRemove;
    });
  }

  get defaultInsets() {
    return this._defaultInsets;
  }

}

export default new SafeAreaInsetsManager();