Rocket.Chat.ReactNative/app/utils/layoutAnimation.js

import { LayoutAnimation } from 'react-native';

import debounce from './debounce';
import { isIOS } from './deviceInfo';

export const animateNextTransition = debounce(() => {
	if (isIOS) {
		LayoutAnimation.configureNext({
			duration: 200,
			create: {
				type: LayoutAnimation.Types.easeInEaseOut,
				property: LayoutAnimation.Properties.opacity
			},
			update: {
				type: LayoutAnimation.Types.easeInEaseOut
			},
			delete: {
				type: LayoutAnimation.Types.easeInEaseOut,
				property: LayoutAnimation.Properties.opacity
			}
		});
	}
}, 200, true);