devextreme/dist/transpiled/ui/scroll_view/animator.js

HTML5 JavaScript Component Suite for Responsive Web Development

"use strict";

var noop = require("../../core/utils/common").noop,
    Class = require("../../core/class"),
    abstract = Class.abstract,
    animationFrame = require("../../animation/frame");

var Animator = Class.inherit({

    ctor: function ctor() {
        this._finished = true;
        this._stopped = false;

        this._proxiedStepCore = this._stepCore.bind(this);
    },

    start: function start() {
        this._stopped = false;
        this._finished = false;
        this._stepCore();
    },

    stop: function stop() {
        this._stopped = true;
        animationFrame.cancelAnimationFrame(this._stepAnimationFrame);
    },

    _stepCore: function _stepCore() {
        if (this._isStopped()) {
            this._stop();
            return;
        }

        if (this._isFinished()) {
            this._finished = true;
            this._complete();
            return;
        }

        this._step();
        this._stepAnimationFrame = animationFrame.requestAnimationFrame(this._proxiedStepCore);
    },

    _step: abstract,
    _isFinished: noop,
    _stop: noop,
    _complete: noop,

    _isStopped: function _isStopped() {
        return this._stopped;
    },

    inProgress: function inProgress() {
        return !(this._stopped || this._finished);
    }

});

module.exports = Animator;