import React, { forwardRef } from 'react'; import { Animated } from 'react-native'; import type { ISupportedTransitions, ITransitionConfig, ITransitionProps, } from './types'; const transformStylesMap = { translateY: true, translateX: true, scale: true, scaleX: true, scaleY: true, rotate: true, }; const defaultStyles = { opacity: 1, translateY: 0, translateX: 0, scale: 1, scaleX: 1, scaleY: 1, rotate: '0deg', }; const getAnimatedStyles = (animateValue: any) => ( initial: ISupportedTransitions, to: ISupportedTransitions ) => { const styles: any = { transform: [], }; for (let key in initial) { if (key === 'transition') { continue; } if (key in transformStylesMap) { styles.transform?.push({ [key]: animateValue.interpolate({ inputRange: [0, 1], outputRange: [(initial as any)[key], (to as any)[key]], }), } as any); } else { styles[key] = animateValue.interpolate({ inputRange: [0, 1], outputRange: [(initial as any)[key], (to as any)[key]], }); } } return styles; }; const defaultTransitionConfig: ITransitionConfig = { type: 'timing', useNativeDriver: true, duration: 250, delay: 0, }; export const Transition = forwardRef( ( { children, onTransitionComplete, visible = false, initial, animate, exit, style, as, ...rest }: ITransitionProps, ref: any ) => { const animateValue = React.useRef(new Animated.Value(0)).current; const Component = React.useMemo(() => { if (as) { return Animated.createAnimatedComponent(as); } return Animated.View; }, [as]); const [animationState, setAnimationState] = React.useState( visible ? 'entering' : 'exited' ); const prevVisible = React.useRef(visible); React.useEffect( function startEntryTransition() { const entryTransition = { ...defaultTransitionConfig, ...animate?.transition, }; if (visible) { Animated.sequence([ // @ts-ignore - delay is present in defaultTransitionConfig Animated.delay(entryTransition.delay), Animated[entryTransition.type ?? 'timing'](animateValue, { toValue: 1, useNativeDriver: true, ...entryTransition, }), ]).start(() => { setAnimationState('entered'); }); } }, [visible, onTransitionComplete, animateValue, animate] ); React.useEffect(() => { // Exit request if (prevVisible.current !== visible && !visible) { setAnimationState('exiting'); } prevVisible.current = visible; }, [visible]); React.useEffect( function startExitTransition() { const exitTransition = { ...defaultTransitionConfig, ...exit?.transition, }; if (animationState === 'exiting') { Animated.sequence([ // @ts-ignore - delay is present in defaultTransitionConfig Animated.delay(exitTransition.delay), Animated[exitTransition.type ?? 'timing'](animateValue, { toValue: 0, useNativeDriver: true, ...exitTransition, }), ]).start(() => { setAnimationState('exited'); }); } }, [ exit, onTransitionComplete, setAnimationState, animationState, animateValue, ] ); // If exit animation is present and state is exiting, we replace 'initial' with 'exit' animation initial = animationState === 'exiting' && exit ? { ...defaultStyles, ...exit } : { ...defaultStyles, ...initial }; animate = { ...defaultStyles, ...animate }; const styles = React.useMemo(() => { return [ getAnimatedStyles(animateValue)( initial as ISupportedTransitions, animate as ISupportedTransitions ), style, ]; }, [animateValue, initial, animate, style]); React.useEffect(() => { if (animationState === 'exited') { onTransitionComplete && onTransitionComplete('exited'); } else if (animationState === 'entered') { onTransitionComplete && onTransitionComplete('entered'); } }, [animationState, onTransitionComplete]); return ( {children} ); } );