@moxy/react-page-swapper/es/SwapTransition.js

An orchestrator that eases out the implementation of page transitions

import _omit from "lodash/omit";

function _defineProperty(obj, key, value) { if (key in obj) { Object.defineProperty(obj, key, { value: value, enumerable: true, configurable: true, writable: true }); } else { obj[key] = value; } return obj; }

import { Component } from 'react';
import PropTypes from 'prop-types';
import shallowequal from 'shallowequal';
import memoizeOne from 'memoize-one';
import once from 'once';
export default class SwapTransition extends Component {
  constructor(...args) {
    super(...args);

    _defineProperty(this, "state", {
      transitioning: false
    });

    _defineProperty(this, "wrapOnEntered", memoizeOne(onEntered => once(async () => {
      const {
        in: inProp,
        transitioning
      } = this.state;

      if (!inProp || !transitioning) {
        return;
      }

      await Promise.resolve();
      this.setState({
        transitioning: false
      }, () => {
        onEntered === null || onEntered === void 0 ? void 0 : onEntered();
      });
    })));

    _defineProperty(this, "wrapOnExited", memoizeOne(onExited => once(async () => {
      const {
        in: inProp,
        transitioning
      } = this.state;

      if (inProp || !transitioning) {
        return;
      }

      await Promise.resolve(); // `transitioning` is not changed to false as the view will be unmounted afterwards
      // This effectively avoids one useless re-render

      onExited === null || onExited === void 0 ? void 0 : onExited();
    })));
  }

  static getDerivedStateFromProps(props, state) {
    let transitioning; // Transitioning is set to true if the `in` prop changed
    // There's an exception which is when mounting, which we take into consideration the `hasPrevNode` prop

    if (props.in !== state.in) {
      transitioning = state.in == null ? !!props.prevNodeKey : true;
    } else {
      transitioning = state.transitioning;
    }

    return { // TransitionGroup adds the properties below, so we filter them out
      ..._omit(props, ['appear', 'enter', 'exit', 'onExited']),
      // TransitionGroup changes `onExited` in every render unnecessarily,
      // so we keep it constant to avoid re-renders
      onExited: state.onExited || props.onExited,
      transitioning
    };
  }

  shouldComponentUpdate(prevProps, prevState) {
    // Only update when state changes, which was derived in `getDerivedStateFromProps`
    return !shallowequal(this.state, prevState);
  }

  render() {
    const {
      children,
      onEntered,
      onExited,
      ...rest
    } = this.state;
    return children({ ...rest,
      onEntered: this.wrapOnEntered(onEntered),
      onExited: this.wrapOnExited(onExited)
    });
  } // eslint-disable-next-line react/sort-comp


}

_defineProperty(SwapTransition, "propTypes", {
  node: PropTypes.element.isRequired,
  nodeKey: PropTypes.string.isRequired,
  prevNodeKey: PropTypes.string,
  mode: PropTypes.oneOf(['simultaneous', 'out-in']).isRequired,
  animation: PropTypes.string,
  in: PropTypes.bool,
  style: PropTypes.object,
  onEntered: PropTypes.func,
  onExited: PropTypes.func,
  children: PropTypes.func.isRequired
});

_defineProperty(SwapTransition, "defaultProps", {
  in: false,
  style: {}
});