animated/lib/DecayAnimation.js

Declarative Animations Library for React and React Native

'use strict';var _createClass=function(){function defineProperties(target,props){for(var i=0;i<props.length;i++){var descriptor=props[i];descriptor.enumerable=descriptor.enumerable||false;descriptor.configurable=true;if("value"in descriptor)descriptor.writable=true;Object.defineProperty(target,descriptor.key,descriptor);}}return function(Constructor,protoProps,staticProps){if(protoProps)defineProperties(Constructor.prototype,protoProps);if(staticProps)defineProperties(Constructor,staticProps);return Constructor;};}();function _classCallCheck(instance,Constructor){if(!(instance instanceof Constructor)){throw new TypeError("Cannot call a class as a function");}}function _possibleConstructorReturn(self,call){if(!self){throw new ReferenceError("this hasn't been initialised - super() hasn't been called");}return call&&(typeof call==="object"||typeof call==="function")?call:self;}function _inherits(subClass,superClass){if(typeof superClass!=="function"&&superClass!==null){throw new TypeError("Super expression must either be null or a function, not "+typeof superClass);}subClass.prototype=Object.create(superClass&&superClass.prototype,{constructor:{value:subClass,enumerable:false,writable:true,configurable:true}});if(superClass)Object.setPrototypeOf?Object.setPrototypeOf(subClass,superClass):subClass.__proto__=superClass;}

var Animation=require('./Animation');
var RequestAnimationFrame=require('./injectable/RequestAnimationFrame');
var CancelAnimationFrame=require('./injectable/CancelAnimationFrame');var








DecayAnimation=function(_Animation){_inherits(DecayAnimation,_Animation);








function DecayAnimation(
config)
{_classCallCheck(this,DecayAnimation);var _this=_possibleConstructorReturn(this,(DecayAnimation.__proto__||Object.getPrototypeOf(DecayAnimation)).call(this));

_this._deceleration=config.deceleration!==undefined?config.deceleration:0.998;
_this._velocity=config.velocity;
_this.__isInteraction=config.isInteraction!==undefined?config.isInteraction:true;return _this;
}_createClass(DecayAnimation,[{key:'start',value:function start(


fromValue,
onUpdate,
onEnd)
{
this.__active=true;
this._lastValue=fromValue;
this._fromValue=fromValue;
this._onUpdate=onUpdate;
this.__onEnd=onEnd;
this._startTime=Date.now();
this._animationFrame=RequestAnimationFrame.current(this.onUpdate.bind(this));
}},{key:'onUpdate',value:function onUpdate()

{
var now=Date.now();

var value=this._fromValue+
this._velocity/(1-this._deceleration)*(
1-Math.exp(-(1-this._deceleration)*(now-this._startTime)));

this._onUpdate(value);

if(Math.abs(this._lastValue-value)<0.1){
this.__debouncedOnEnd({finished:true});
return;
}

this._lastValue=value;
if(this.__active){
this._animationFrame=RequestAnimationFrame.current(this.onUpdate.bind(this));
}
}},{key:'stop',value:function stop()

{
this.__active=false;
CancelAnimationFrame.current(this._animationFrame);
this.__debouncedOnEnd({finished:false});
}}]);return DecayAnimation;}(Animation);


module.exports=DecayAnimation;