static/components/sticky.js
/*!
* # Semantic UI 1.12.3 - Sticky
* http://github.com/semantic-org/semantic-ui/
*
*
* Copyright 2014 Contributorss
* Released under the MIT license
* http://opensource.org/licenses/MIT
*
*/
;(function ( $, window, document, undefined ) {
"use strict";
$.fn.sticky = function(parameters) {
var
$allModules = $(this),
moduleSelector = $allModules.selector || '',
time = new Date().getTime(),
performance = [],
query = arguments[0],
methodInvoked = (typeof query == 'string'),
queryArguments = [].slice.call(arguments, 1),
returnedValue
;
$allModules
.each(function() {
var
settings = ( $.isPlainObject(parameters) )
? $.extend(true, {}, $.fn.sticky.settings, parameters)
: $.extend({}, $.fn.sticky.settings),
className = settings.className,
namespace = settings.namespace,
error = settings.error,
eventNamespace = '.' + namespace,
moduleNamespace = 'module-' + namespace,
$module = $(this),
$window = $(window),
$container = $module.offsetParent(),
$scroll = $(settings.scrollContext),
$context,
selector = $module.selector || '',
instance = $module.data(moduleNamespace),
requestAnimationFrame = window.requestAnimationFrame
|| window.mozRequestAnimationFrame
|| window.webkitRequestAnimationFrame
|| window.msRequestAnimationFrame
|| function(callback) { setTimeout(callback, 0); },
element = this,
observer,
module
;
module = {
initialize: function() {
module.determineContext();
module.verbose('Initializing sticky', settings, $container);
module.save.positions();
module.checkErrors();
module.bind.events();
if(settings.observeChanges) {
module.observeChanges();
}
module.instantiate();
},
instantiate: function() {
module.verbose('Storing instance of module', module);
instance = module;
$module
.data(moduleNamespace, module)
;
},
destroy: function() {
module.verbose('Destroying previous instance');
module.reset();
if(observer) {
observer.disconnect();
}
$window
.off('load' + eventNamespace, module.event.load)
.off('resize' + eventNamespace, module.event.resize)
;
$scroll
.off('scrollchange' + eventNamespace, module.event.scrollchange)
;
$module.removeData(moduleNamespace);
},
observeChanges: function() {
var
context = $context[0]
;
if('MutationObserver' in window) {
observer = new MutationObserver(function(mutations) {
clearTimeout(module.timer);
module.timer = setTimeout(function() {
module.verbose('DOM tree modified, updating sticky menu');
module.refresh();
}, 100);
});
observer.observe(element, {
childList : true,
subtree : true
});
observer.observe(context, {
childList : true,
subtree : true
});
module.debug('Setting up mutation observer', observer);
}
},
determineContext: function() {
if(settings.context) {
$context = $(settings.context);
}
else {
$context = $container;
}
if($context.length === 0) {
module.error(error.invalidContext, settings.context, $module);
return;
}
},
checkErrors: function() {
if( module.is.hidden() ) {
module.error(error.visible, $module);
}
if(module.cache.element.height > module.cache.context.height) {
module.reset();
module.error(error.elementSize, $module);
return;
}
},
bind: {
events: function() {
$window
.on('load' + eventNamespace, module.event.load)
.on('resize' + eventNamespace, module.event.resize)
;
// pub/sub pattern
$scroll
.off('scroll' + eventNamespace)
.on('scroll' + eventNamespace, module.event.scroll)
.on('scrollchange' + eventNamespace, module.event.scrollchange)
;
}
},
event: {
load: function() {
module.verbose('Page contents finished loading');
requestAnimationFrame(module.refresh);
},
resize: function() {
module.verbose('Window resized');
requestAnimationFrame(module.refresh);
},
scroll: function() {
requestAnimationFrame(function() {
$scroll.trigger('scrollchange' + eventNamespace, $scroll.scrollTop() );
});
},
scrollchange: function(event, scrollPosition) {
module.stick(scrollPosition);
settings.onScroll.call(element);
}
},
refresh: function(hardRefresh) {
module.reset();
if(hardRefresh) {
$container = $module.offsetParent();
}
module.save.positions();
module.stick();
settings.onReposition.call(element);
},
supports: {
sticky: function() {
var
$element = $('<div/>'),
element = $element.get()
;
$element.addClass(className.supported);
return($element.css('position').match('sticky'));
}
},
save: {
lastScroll: function(scroll) {
module.lastScroll = scroll;
},
positions: function() {
var
window = {
height: $window.height()
},
element = {
margin: {
top : parseInt($module.css('margin-top'), 10),
bottom : parseInt($module.css('margin-bottom'), 10),
},
offset : $module.offset(),
width : $module.outerWidth(),
height : $module.outerHeight()
},
context = {
offset : $context.offset(),
height : $context.outerHeight(),
bottomPadding : parseInt($context.css('padding-bottom'), 10)
}
;
module.cache = {
fits : ( element.height < window.height ),
window: {
height: window.height
},
element: {
margin : element.margin,
top : element.offset.top - element.margin.top,
left : element.offset.left,
width : element.width,
height : element.height,
bottom : element.offset.top + element.height
},
context: {
top : context.offset.top,
height : context.height,
bottomPadding : context.bottomPadding,
bottom : context.offset.top + context.height - context.bottomPadding
}
};
module.set.containerSize();
module.set.size();
module.stick();
module.debug('Caching element positions', module.cache);
}
},
get: {
direction: function(scroll) {
var
direction = 'down'
;
scroll = scroll || $scroll.scrollTop();
if(module.lastScroll !== undefined) {
if(module.lastScroll < scroll) {
direction = 'down';
}
else if(module.lastScroll > scroll) {
direction = 'up';
}
}
return direction;
},
scrollChange: function(scroll) {
scroll = scroll || $scroll.scrollTop();
return (module.lastScroll)
? (scroll - module.lastScroll)
: 0
;
},
currentElementScroll: function() {
return ( module.is.top() )
? Math.abs(parseInt($module.css('top'), 10)) || 0
: Math.abs(parseInt($module.css('bottom'), 10)) || 0
;
},
elementScroll: function(scroll) {
scroll = scroll || $scroll.scrollTop();
var
element = module.cache.element,
window = module.cache.window,
delta = module.get.scrollChange(scroll),
maxScroll = (element.height - window.height + settings.offset),
elementScroll = module.get.currentElementScroll(),
possibleScroll = (elementScroll + delta),
elementScroll
;
if(module.cache.fits || possibleScroll < 0) {
elementScroll = 0;
}
else if(possibleScroll > maxScroll ) {
elementScroll = maxScroll;
}
else {
elementScroll = possibleScroll;
}
return elementScroll;
}
},
remove: {
offset: function() {
$module.css('margin-top', '');
}
},
set: {
offset: function() {
module.verbose('Setting offset on element', settings.offset);
$module.css('margin-top', settings.offset);
},
containerSize: function() {
var
tagName = $container.get(0).tagName
;
if(tagName === 'HTML' || tagName == 'body') {
// this can trigger for too many reasons
//module.error(error.container, tagName, $module);
$container = $module.offsetParent();
}
else {
if( Math.abs($container.height() - module.cache.context.height) > 5) {
module.debug('Context has padding, specifying exact height for container', module.cache.context.height);
$container.css({
height: module.cache.context.height
});
}
}
},
scroll: function(scroll) {
module.debug('Setting scroll on element', scroll);
if( module.is.top() ) {
$module
.css('bottom', '')
.css('top', -scroll)
;
}
if( module.is.bottom() ) {
$module
.css('top', '')
.css('bottom', scroll)
;
}
},
size: function() {
if(module.cache.element.height !== 0 && module.cache.element.width !== 0) {
$module
.css({
width : module.cache.element.width,
height : module.cache.element.height
})
;
}
}
},
is: {
top: function() {
return $module.hasClass(className.top);
},
bottom: function() {
return $module.hasClass(className.bottom);
},
initialPosition: function() {
return (!module.is.fixed() && !module.is.bound());
},
hidden: function() {
return (!$module.is(':visible'));
},
bound: function() {
return $module.hasClass(className.bound);
},
fixed: function() {
return $module.hasClass(className.fixed);
}
},
stick: function(scroll) {
var
cachedPosition = scroll || $scroll.scrollTop(),
cache = module.cache,
fits = cache.fits,
element = cache.element,
window = cache.window,
context = cache.context,
offset = (module.is.bottom() && settings.pushing)
? settings.bottomOffset
: settings.offset,
scroll = {
top : cachedPosition + offset,
bottom : cachedPosition + offset + window.height
},
direction = module.get.direction(scroll.top),
elementScroll = (fits)
? 0
: module.get.elementScroll(scroll.top),
// shorthand
doesntFit = !fits,
elementVisible = (element.height !== 0)
;
// save current scroll for next run
module.save.lastScroll(scroll.top);
if(elementVisible) {
if( module.is.initialPosition() ) {
if(scroll.top >= context.bottom) {
module.debug('Element bottom of container');
module.bindBottom();
}
else if(scroll.top >= element.top) {
module.debug('Element passed, fixing element to page');
module.fixTop();
}
}
else if( module.is.fixed() ) {
// currently fixed top
if( module.is.top() ) {
if( scroll.top < element.top ) {
module.debug('Fixed element reached top of container');
module.setInitialPosition();
}
else if( (element.height + scroll.top - elementScroll) > context.bottom ) {
module.debug('Fixed element reached bottom of container');
module.bindBottom();
}
// scroll element if larger than screen
else if(doesntFit) {
module.set.scroll(elementScroll);
}
}
// currently fixed bottom
else if(module.is.bottom() ) {
// top edge
if( (scroll.bottom - element.height) < element.top) {
module.debug('Bottom fixed rail has reached top of container');
module.setInitialPosition();
}
// bottom edge
else if(scroll.bottom > context.bottom) {
module.debug('Bottom fixed rail has reached bottom of container');
module.bindBottom();
}
// scroll element if larger than screen
else if(doesntFit) {
module.set.scroll(elementScroll);
}
}
}
else if( module.is.bottom() ) {
if(settings.pushing) {
if(module.is.bound() && scroll.bottom < context.bottom ) {
module.debug('Fixing bottom attached element to bottom of browser.');
module.fixBottom();
}
}
else {
if(module.is.bound() && (scroll.top < context.bottom - element.height) ) {
module.debug('Fixing bottom attached element to top of browser.');
module.fixTop();
}
}
}
}
},
bindTop: function() {
module.debug('Binding element to top of parent container');
module.remove.offset();
$module
.css('left' , '')
.css('top' , '')
.css('margin-bottom' , '')
.removeClass(className.fixed)
.removeClass(className.bottom)
.addClass(className.bound)
.addClass(className.top)
;
settings.onTop.call(element);
settings.onUnstick.call(element);
},
bindBottom: function() {
module.debug('Binding element to bottom of parent container');
module.remove.offset();
$module
.css('left' , '')
.css('top' , '')
.css('margin-bottom' , module.cache.context.bottomPadding)
.removeClass(className.fixed)
.removeClass(className.top)
.addClass(className.bound)
.addClass(className.bottom)
;
settings.onBottom.call(element);
settings.onUnstick.call(element);
},
setInitialPosition: function() {
module.unfix();
module.unbind();
},
fixTop: function() {
module.debug('Fixing element to top of page');
module.set.offset();
$module
.css('left', module.cache.element.left)
.css('bottom' , '')
.removeClass(className.bound)
.removeClass(className.bottom)
.addClass(className.fixed)
.addClass(className.top)
;
settings.onStick.call(element);
},
fixBottom: function() {
module.debug('Sticking element to bottom of page');
module.set.offset();
$module
.css('left', module.cache.element.left)
.css('bottom' , '')
.removeClass(className.bound)
.removeClass(className.top)
.addClass(className.fixed)
.addClass(className.bottom)
;
settings.onStick.call(element);
},
unbind: function() {
module.debug('Removing absolute position on element');
module.remove.offset();
$module
.removeClass(className.bound)
.removeClass(className.top)
.removeClass(className.bottom)
;
},
unfix: function() {
module.debug('Removing fixed position on element');
module.remove.offset();
$module
.removeClass(className.fixed)
.removeClass(className.top)
.removeClass(className.bottom)
;
settings.onUnstick.call(element);
},
reset: function() {
module.debug('Reseting elements position');
module.unbind();
module.unfix();
module.resetCSS();
module.remove.offset();
},
resetCSS: function() {
$module
.css({
width : '',
height : ''
})
;
$container
.css({
height: ''
})
;
},
setting: function(name, value) {
if( $.isPlainObject(name) ) {
$.extend(true, settings, name);
}
else if(value !== undefined) {
settings[name] = value;
}
else {
return settings[name];
}
},
internal: function(name, value) {
if( $.isPlainObject(name) ) {
$.extend(true, module, name);
}
else if(value !== undefined) {
module[name] = value;
}
else {
return module[name];
}
},
debug: function() {
if(settings.debug) {
if(settings.performance) {
module.performance.log(arguments);
}
else {
module.debug = Function.prototype.bind.call(console.info, console, settings.name + ':');
module.debug.apply(console, arguments);
}
}
},
verbose: function() {
if(settings.verbose && settings.debug) {
if(settings.performance) {
module.performance.log(arguments);
}
else {
module.verbose = Function.prototype.bind.call(console.info, console, settings.name + ':');
module.verbose.apply(console, arguments);
}
}
},
error: function() {
module.error = Function.prototype.bind.call(console.error, console, settings.name + ':');
module.error.apply(console, arguments);
},
performance: {
log: function(message) {
var
currentTime,
executionTime,
previousTime
;
if(settings.performance) {
currentTime = new Date().getTime();
previousTime = time || currentTime;
executionTime = currentTime - previousTime;
time = currentTime;
performance.push({
'Name' : message[0],
'Arguments' : [].slice.call(message, 1) || '',
'Element' : element,
'Execution Time' : executionTime
});
}
clearTimeout(module.performance.timer);
module.performance.timer = setTimeout(module.performance.display, 0);
},
display: function() {
var
title = settings.name + ':',
totalTime = 0
;
time = false;
clearTimeout(module.performance.timer);
$.each(performance, function(index, data) {
totalTime += data['Execution Time'];
});
title += ' ' + totalTime + 'ms';
if(moduleSelector) {
title += ' \'' + moduleSelector + '\'';
}
if( (console.group !== undefined || console.table !== undefined) && performance.length > 0) {
console.groupCollapsed(title);
if(console.table) {
console.table(performance);
}
else {
$.each(performance, function(index, data) {
console.log(data['Name'] + ': ' + data['Execution Time']+'ms');
});
}
console.groupEnd();
}
performance = [];
}
},
invoke: function(query, passedArguments, context) {
var
object = instance,
maxDepth,
found,
response
;
passedArguments = passedArguments || queryArguments;
context = element || context;
if(typeof query == 'string' && object !== undefined) {
query = query.split(/[\. ]/);
maxDepth = query.length - 1;
$.each(query, function(depth, value) {
var camelCaseValue = (depth != maxDepth)
? value + query[depth + 1].charAt(0).toUpperCase() + query[depth + 1].slice(1)
: query
;
if( $.isPlainObject( object[camelCaseValue] ) && (depth != maxDepth) ) {
object = object[camelCaseValue];
}
else if( object[camelCaseValue] !== undefined ) {
found = object[camelCaseValue];
return false;
}
else if( $.isPlainObject( object[value] ) && (depth != maxDepth) ) {
object = object[value];
}
else if( object[value] !== undefined ) {
found = object[value];
return false;
}
else {
return false;
}
});
}
if ( $.isFunction( found ) ) {
response = found.apply(context, passedArguments);
}
else if(found !== undefined) {
response = found;
}
if($.isArray(returnedValue)) {
returnedValue.push(response);
}
else if(returnedValue !== undefined) {
returnedValue = [returnedValue, response];
}
else if(response !== undefined) {
returnedValue = response;
}
return found;
}
};
if(methodInvoked) {
if(instance === undefined) {
module.initialize();
}
module.invoke(query);
}
else {
if(instance !== undefined) {
instance.invoke('destroy');
}
module.initialize();
}
})
;
return (returnedValue !== undefined)
? returnedValue
: this
;
};
$.fn.sticky.settings = {
name : 'Sticky',
namespace : 'sticky',
debug : false,
verbose : false,
performance : false,
pushing : false,
context : false,
scrollContext : window,
offset : 0,
bottomOffset : 0,
observeChanges : true,
onReposition : function(){},
onScroll : function(){},
onStick : function(){},
onUnstick : function(){},
onTop : function(){},
onBottom : function(){},
error : {
container : 'Sticky element must be inside a relative container',
visible : 'Element is hidden, you must call refresh after element becomes visible',
method : 'The method you called is not defined.',
invalidContext : 'Context specified does not exist',
elementSize : 'Sticky element is larger than its container, cannot create sticky.'
},
className : {
bound : 'bound',
fixed : 'fixed',
supported : 'native',
top : 'top',
bottom : 'bottom'
}
};
})( jQuery, window , document );