mobify/velocity

Accelerated JavaScript animation.

velocity's Issues

We should add a Changelog or Release page

Readme needs to be updated

We should clarify what's different between our Velocity and core Velocity.

'container' option causes animation to fail, when using Zepto object as value

CC @tedtate @donnielrt

Background

• When performing a scroll animation, Velocity will allow you to scroll an element into view of a containing element, rather than window --- this is done by providing a container option
• Take a look at the following example usage:

$.fn.velocity($('.element'), 'scroll', {
        'container': $('.container')
});

• Unfortunately, using $('.element') (a Zepto object) as the value for 'container' will result in the animation function executing, but failing silently (i.e. no animation occurs but no error is thrown either). Providing a raw DOM node (e.g. $('.container')[0]) or a desktop jQuery selection instead will work correctly.

Problem

• The isWrapped function, https://github.com/mobify/velocity/blob/master/velocity.js#L520:

isWrapped: function (variable) {
    return variable && (variable.jquery || (window.Zepto && window.Zepto.zepto.isZ(variable)));
},

• The check for window.Zepto && window.Zepto.zepto.isZ(variable) will fail due to the way we include Zepto as our selector library in adaptive.js projects. window.Zepto.zepto.isZ will always return false
• For posterity, here's the related code in zepto.js:

zepto.Z = function(dom, selector) {
    dom = dom || []
    dom.__proto__ = $.fn
    dom.selector = selector || ''
    return dom
}

zepto.isZ = function(object) {
    return object instanceof zepto.Z
}

Notes

• See http://julian.com/research/velocity/#scroll for documentation on the 'container' option