react-native/Libraries/LayoutAnimation/LayoutAnimation.js

/**
 * Copyright (c) 2015-present, Facebook, Inc.
 *
 * This source code is licensed under the MIT license found in the
 * LICENSE file in the root directory of this source tree.
 *
 * @providesModule LayoutAnimation
 * @flow
 * @format
 */
'use strict';

const PropTypes = require('prop-types');
const UIManager = require('UIManager');

/* $FlowFixMe(>=0.54.0 site=react_native_oss) This comment suppresses an error
 * found when Flow v0.54 was deployed. To see the error delete this comment and
 * run Flow. */
const keyMirror = require('fbjs/lib/keyMirror');

const {checkPropTypes} = PropTypes;

const TypesEnum = {
  spring: true,
  linear: true,
  easeInEaseOut: true,
  easeIn: true,
  easeOut: true,
  keyboard: true,
};
const Types = keyMirror(TypesEnum);

const PropertiesEnum = {
  opacity: true,
  scaleX: true,
  scaleY: true,
  scaleXY: true,
};
const Properties = keyMirror(PropertiesEnum);

const animType = PropTypes.shape({
  duration: PropTypes.number,
  delay: PropTypes.number,
  springDamping: PropTypes.number,
  initialVelocity: PropTypes.number,
  type: PropTypes.oneOf(Object.keys(Types)).isRequired,
  property: PropTypes.oneOf(
    // Only applies to create/delete
    Object.keys(Properties),
  ),
});

type Anim = {
  duration?: number,
  delay?: number,
  springDamping?: number,
  initialVelocity?: number,
  type?: $Enum<typeof TypesEnum>,
  property?: $Enum<typeof PropertiesEnum>,
};

const configType = PropTypes.shape({
  duration: PropTypes.number.isRequired,
  create: animType,
  update: animType,
  delete: animType,
});

type Config = {
  duration: number,
  create?: Anim,
  update?: Anim,
  delete?: Anim,
};

function checkConfig(config: Config, location: string, name: string) {
  checkPropTypes({config: configType}, {config}, location, name);
}

function configureNext(config: Config, onAnimationDidEnd?: Function) {
  if (__DEV__) {
    checkConfig(config, 'config', 'LayoutAnimation.configureNext');
  }
  UIManager.configureNextLayoutAnimation(
    config,
    onAnimationDidEnd || function() {},
    function() {
      /* unused */
    },
  );
}

function create(duration: number, type, creationProp): Config {
  return {
    duration,
    create: {
      type,
      property: creationProp,
    },
    update: {
      type,
    },
    delete: {
      type,
      property: creationProp,
    },
  };
}

const Presets = {
  easeInEaseOut: create(300, Types.easeInEaseOut, Properties.opacity),
  linear: create(500, Types.linear, Properties.opacity),
  spring: {
    duration: 700,
    create: {
      type: Types.linear,
      property: Properties.opacity,
    },
    update: {
      type: Types.spring,
      springDamping: 0.4,
    },
    delete: {
      type: Types.linear,
      property: Properties.opacity,
    },
  },
};

/**
 * Automatically animates views to their new positions when the
 * next layout happens.
 *
 * A common way to use this API is to call it before calling `setState`.
 *
 * Note that in order to get this to work on **Android** you need to set the following flags via `UIManager`:
 *
 *     UIManager.setLayoutAnimationEnabledExperimental && UIManager.setLayoutAnimationEnabledExperimental(true);
 */
const LayoutAnimation = {
  /**
   * Schedules an animation to happen on the next layout.
   *
   * @param config Specifies animation properties:
   *
   *   - `duration` in milliseconds
   *   - `create`, config for animating in new views (see `Anim` type)
   *   - `update`, config for animating views that have been updated
   * (see `Anim` type)
   *
   * @param onAnimationDidEnd Called when the animation finished.
   * Only supported on iOS.
   * @param onError Called on error. Only supported on iOS.
   */
  configureNext,
  /**
   * Helper for creating a config for `configureNext`.
   */
  create,
  Types,
  Properties,
  checkConfig,
  Presets,
  easeInEaseOut: configureNext.bind(null, Presets.easeInEaseOut),
  linear: configureNext.bind(null, Presets.linear),
  spring: configureNext.bind(null, Presets.spring),
};

module.exports = LayoutAnimation;