I've been struggling trying to get Ram Swaroop's animateScroll.js to work with Telerik's AppBuilder.
I need the nice fine-grained control of animateScroll, like pre and post scroll event handling, animation easing and controllable scrolling speed (!). However, no matter what I do the scrolling behavior won't actually happen, even though the jquery animate code that does the work (line 162 ) of animateScroll does seem to fire, at as near as I can tell by instrumenting with console.log.
To be clear the behavior I am after is the method in animatescroll where you are scrolling within an existing element as opposed to the default behavior of scrolling the whole page. Scrolling within an element is achieved referencing the containing element as a parameter. Effectively, this approach turns an arbitrary containing div into a "scroller" and can be seen in the demo under the parameter section.
I have a large appbuilder project, so I made an essentially empty appbuilder project from Telerik's demo templates and I get the same result. My assumption is this issue would also affect since Phone and Cordova since they are very, very similar. If anyone is able to help with this I'll do my best to submit the tweaked version under the same MIT license to the various cordova/phonegap plugin directories. It's a really nice scroller - if I can get it to work in a hybrid mobile app context.
Any suggestions or help appreciated. Html code from the non-working demo project follows, then followed by the complete source of the animatescroll plugin.
Thanks, Dave Gerding
<div data-role="view" data-title="Home" data-layout="main" data-model="APP.models.home">
<h1 data-bind="html: title"></h1>
<div>
For Example:<br />
<div id="element-demo">
<p>
<button onclick="$('#last-paragraph').animatescroll({element:'#element-demo',padding:20});">Click here</button> to scroll to the last paragraph within this "div" element
</p>
<p>
This "div" element has a class-name "element-demo" which is the value passed for "element" option while calling the plugin.
</p>
<p>
Compzets.com is India's first open source software and freeware publishing site, Download and Upload Open source software and Freeware relevant to the Paid ones for PC,Mac and Linux.
</p>
<p>
It also makes its own Cloud Applications for making tasks easy. Recently it has launched a new Plugin Showcase too.
</p>
<p>
This website is your source of unprecedented access to all kinds of pc,mac or linux software (Open Source or Freeware only) with detailed coverage of tech infos along with multiple screen shots and moreover you can not only download your favorite gadgets but you can also UPLOAD your own software to reach thousand of audience. Stay connected to all the latest happenings in the gadget world,with regular updates on new software and announcements with the help of our RSS Feed,just at a few clicks!
</p>
<p id="last-paragraph">
The word "Compzets" does not have a literal meaning,it is just derived from the word Gadget which is related to Electronic devices where as Compzets is related to Computer software which are nothing but gadgets for computer.
</p>
<p>
Thanks to <a href="https://plus.google.com/114685591029748634833" target="_blank">Ronan DMP</a> for asking this feature!
</p>
</div>
</div>
AND Ram's animatescroll plugin code:
/*
* @build : 20-07-2013
* @author : Ram swaroop
* @site : Compzets.com
*/
(function ($) {
// defines various easing effects
$.easing['jswing'] = $.easing['swing'];
$.extend($.easing,
{
def: 'easeOutQuad',
swing: function (x, t, b, c, d) {
return $.easing[$.easing.def](x, t, b, c, d);
},
easeInQuad: function (x, t, b, c, d) {
return c * (t /= d) * t + b;
},
easeOutQuad: function (x, t, b, c, d) {
return -c * (t /= d) * (t - 2) + b;
},
easeInOutQuad: function (x, t, b, c, d) {
if ((t /= d / 2) < 1) return c / 2 * t * t + b;
return -c / 2 * ((--t) * (t - 2) - 1) + b;
},
easeInCubic: function (x, t, b, c, d) {
return c * (t /= d) * t * t + b;
},
easeOutCubic: function (x, t, b, c, d) {
return c * ((t = t / d - 1) * t * t + 1) + b;
},
easeInOutCubic: function (x, t, b, c, d) {
if ((t /= d / 2) < 1) return c / 2 * t * t * t + b;
return c / 2 * ((t -= 2) * t * t + 2) + b;
},
easeInQuart: function (x, t, b, c, d) {
return c * (t /= d) * t * t * t + b;
},
easeOutQuart: function (x, t, b, c, d) {
return -c * ((t = t / d - 1) * t * t * t - 1) + b;
},
easeInOutQuart: function (x, t, b, c, d) {
if ((t /= d / 2) < 1) return c / 2 * t * t * t * t + b;
return -c / 2 * ((t -= 2) * t * t * t - 2) + b;
},
easeInQuint: function (x, t, b, c, d) {
return c * (t /= d) * t * t * t * t + b;
},
easeOutQuint: function (x, t, b, c, d) {
return c * ((t = t / d - 1) * t * t * t * t + 1) + b;
},
easeInOutQuint: function (x, t, b, c, d) {
if ((t /= d / 2) < 1) return c / 2 * t * t * t * t * t + b;
return c / 2 * ((t -= 2) * t * t * t * t + 2) + b;
},
easeInSine: function (x, t, b, c, d) {
return -c * Math.cos(t / d * (Math.PI / 2)) + c + b;
},
easeOutSine: function (x, t, b, c, d) {
return c * Math.sin(t / d * (Math.PI / 2)) + b;
},
easeInOutSine: function (x, t, b, c, d) {
return -c / 2 * (Math.cos(Math.PI * t / d) - 1) + b;
},
easeInExpo: function (x, t, b, c, d) {
return (t == 0) ? b : c * Math.pow(2, 10 * (t / d - 1)) + b;
},
easeOutExpo: function (x, t, b, c, d) {
return (t == d) ? b + c : c * (-Math.pow(2, -10 * t / d) + 1) + b;
},
easeInOutExpo: function (x, t, b, c, d) {
if (t == 0) return b;
if (t == d) return b + c;
if ((t /= d / 2) < 1) return c / 2 * Math.pow(2, 10 * (t - 1)) + b;
return c / 2 * (-Math.pow(2, -10 * --t) + 2) + b;
},
easeInCirc: function (x, t, b, c, d) {
return -c * (Math.sqrt(1 - (t /= d) * t) - 1) + b;
},
easeOutCirc: function (x, t, b, c, d) {
return c * Math.sqrt(1 - (t = t / d - 1) * t) + b;
},
easeInOutCirc: function (x, t, b, c, d) {
if ((t /= d / 2) < 1) return -c / 2 * (Math.sqrt(1 - t * t) - 1) + b;
return c / 2 * (Math.sqrt(1 - (t -= 2) * t) + 1) + b;
},
easeInElastic: function (x, t, b, c, d) {
var s = 1.70158; var p = 0; var a = c;
if (t == 0) return b; if ((t /= d) == 1) return b + c; if (!p) p = d * .3;
if (a < Math.abs(c)) { a = c; var s = p / 4; }
else var s = p / (2 * Math.PI) * Math.asin(c / a);
return -(a * Math.pow(2, 10 * (t -= 1)) * Math.sin((t * d - s) * (2 * Math.PI) / p)) + b;
},
easeOutElastic: function (x, t, b, c, d) {
var s = 1.70158; var p = 0; var a = c;
if (t == 0) return b; if ((t /= d) == 1) return b + c; if (!p) p = d * .3;
if (a < Math.abs(c)) { a = c; var s = p / 4; }
else var s = p / (2 * Math.PI) * Math.asin(c / a);
return a * Math.pow(2, -10 * t) * Math.sin((t * d - s) * (2 * Math.PI) / p) + c + b;
},
easeInOutElastic: function (x, t, b, c, d) {
var s = 1.70158; var p = 0; var a = c;
if (t == 0) return b; if ((t /= d / 2) == 2) return b + c; if (!p) p = d * (.3 * 1.5);
if (a < Math.abs(c)) { a = c; var s = p / 4; }
else var s = p / (2 * Math.PI) * Math.asin(c / a);
if (t < 1) return -.5 * (a * Math.pow(2, 10 * (t -= 1)) * Math.sin((t * d - s) * (2 * Math.PI) / p)) + b;
return a * Math.pow(2, -10 * (t -= 1)) * Math.sin((t * d - s) * (2 * Math.PI) / p) * .5 + c + b;
},
easeInBack: function (x, t, b, c, d, s) {
if (s == undefined) s = 1.70158;
return c * (t /= d) * t * ((s + 1) * t - s) + b;
},
easeOutBack: function (x, t, b, c, d, s) {
if (s == undefined) s = 1.70158;
return c * ((t = t / d - 1) * t * ((s + 1) * t + s) + 1) + b;
},
easeInOutBack: function (x, t, b, c, d, s) {
if (s == undefined) s = 1.70158;
if ((t /= d / 2) < 1) return c / 2 * (t * t * (((s *= (1.525)) + 1) * t - s)) + b;
return c / 2 * ((t -= 2) * t * (((s *= (1.525)) + 1) * t + s) + 2) + b;
},
easeInBounce: function (x, t, b, c, d) {
return c - $.easing.easeOutBounce(x, d - t, 0, c, d) + b;
},
easeOutBounce: function (x, t, b, c, d) {
if ((t /= d) < (1 / 2.75)) {
return c * (7.5625 * t * t) + b;
} else if (t < (2 / 2.75)) {
return c * (7.5625 * (t -= (1.5 / 2.75)) * t + .75) + b;
} else if (t < (2.5 / 2.75)) {
return c * (7.5625 * (t -= (2.25 / 2.75)) * t + .9375) + b;
} else {
return c * (7.5625 * (t -= (2.625 / 2.75)) * t + .984375) + b;
}
},
easeInOutBounce: function (x, t, b, c, d) {
if (t < d / 2) return $.easing.easeInBounce(x, t * 2, 0, c, d) * .5 + b;
return $.easing.easeOutBounce(x, t * 2 - d, 0, c, d) * .5 + c * .5 + b;
}
});
$.fn.animatescroll = function (options) {
// fetches options
var opts = $.extend({}, $.fn.animatescroll.defaults, options);
// make sure the callback is a function
if (typeof opts.onScrollStart == 'function') {
// brings the scope to the callback
opts.onScrollStart.call(this);
}
if (opts.element == "html,body") {
// Get the distance of particular id or class from top
var offset = this.offset().top;
// Scroll the page to the desired position
$(opts.element).stop().animate({ scrollTop: offset - opts.padding }, opts.scrollSpeed, opts.easing);
}
else {
// Scroll the element to the desired position
$(opts.element).stop().animate({ scrollTop: this.offset().top - this.parent().offset().top + this.parent().scrollTop() - opts.padding }, opts.scrollSpeed, opts.easing);
}
setTimeout(function () {
// make sure the callback is a function
if (typeof opts.onScrollEnd == 'function') {
// brings the scope to the callback
opts.onScrollEnd.call(this);
}
}, opts.scrollSpeed);
};
// default options
$.fn.animatescroll.defaults = {
easing: "swing",
scrollSpeed: 800,
padding: 0,
element: "html,body"
};
}(jQuery));
The problem appears to be a known and rather longstanding bug in Android where ScrollTop doesn't quite work.
More related links on Stackoverflow:
I was able to get animatescroll behavior to start functioning simply by adding
The simplest workaround for me was to add an inline style to the container div, so element-demo in the code fragment above becomes:
<div id="element-demo" style="height : 500px; overflow : auto;">
Hoping I can get this to work with my other dynamically generated bits... I'll report back if I find anything more useful.
ADDITION TO ANSWER After a bit more poking and prodding I found another problem and fixed it.
There is what I am pretty sure is a bug in the animatescroll.js library. Specifically, the option that allows you to scroll relative to specified element rather than the default behavior of scrolling to the window or document top. In the current code the option element is used but not completely - animatescroll.js currently assumes the element option is the immediate DOM parent of the element to which you are scrolling. In my case I was scrolling to a span, which was inside a p element which was inside the actual "scroller" element - the containing div.
So, in animatescroll.js I changed this:
$(opts.element).stop().animate({ scrollTop: this.offset().top - this.parent().offset().top + this.parent().scrollTop() - opts.padding }, opts.scrollSpeed, opts.easing);
to this:
$(opts.element).stop().animate({ scrollTop: this.offset().top - $(opts.element).offset().top + $(opts.element).scrollTop() - opts.padding }, opts.scrollSpeed, opts.easing);
And now everything really works. I've notified the author of animatescroll.js so he can update the Git repo assuming he agrees with this approach.