Team:SCU China/jquery.nav
/*
* jQuery One Page Nav Plugin * http://github.com/davist11/jQuery-One-Page-Nav * *
Copyright (c) 2010 Trevor Davis (http://trevordavis.net)
* Dual licensed under the MIT and
GPL licenses.
* Uses the same license as jQuery, see: * http://jquery.org/license * *
@version 3.0.0
* * Example usage: * $('#nav').onePageNav({ * currentClass: 'current', *
changeHash: false,
* scrollSpeed: 750 * }); */
- (function($, window, document, undefined){
// our plugin constructor var OnePageNav = function(elem, options){
this.elem = elem;
this.$elem = $(elem);
this.options = options;
this.metadata = this.$elem.data('plugin-options');
this.$win = $(window);
this.sections = {};
this.didScroll = false;
this.$doc = $(document);
this.docHeight = this.$doc.height();
};
// the plugin prototype
OnePageNav.prototype = {
defaults: {
navItems: 'a',
currentClass: 'current',
changeHash: false,
easing: 'swing',
filter: ,
scrollSpeed: 750,
scrollThreshold: 0.5,
begin: false,
end:
false, scrollChange: false },
init: function() {
// Introduce defaults that can be extended either
//
globally or using an object literal. this.config = $.extend({},
this.defaults, this.options, this.metadata);
this.$nav = this.$elem.find
(this.config.navItems);
//Filter any links out of the nav
if(this.config.filter !== ) {
this.$nav = this.$nav.filter
(this.config.filter); }
//Handle clicks on the nav
this.$nav.on('click.onePageNav', $.proxy(this.handleClick, this));
//Get the section positions this.getPositions();
//Handle scroll changes this.bindInterval();
//Update the
positions on resize too this.$win.on('resize.onePageNav', $.proxy
(this.getPositions, this));
return this; },
adjustNav: function(self, $parent) { self.$elem.find('.' +
self.config.currentClass).removeClass(self.config.currentClass);
$parent.addClass(self.config.currentClass);
},
bindInterval:
function() { var self = this; var docHeight;
self.$win.on('scroll.onePageNav', function() {
self.didScroll = true;
});
self.t = setInterval
(function() { docHeight = self.$doc.height();
//If it was scrolled if(self.didScroll) {
self.didScroll = false;
self.scrollChange();
}
//If the document height changes
if(docHeight !== self.docHeight) {
self.docHeight = docHeight;
self.getPositions();
}
}, 250);
},
getHash:
function($link) { return $link.attr('href').split('#')[1];
},
getPositions: function() { var self = this;
var linkHref;
var topPos;
var $target;
self.$nav.each(function() { linkHref = self.getHash
($(this)); $target = $('#' + linkHref);
if($target.length) { topPos = $target.offset().top;
self.sections[linkHref] = Math.round(topPos);
}
});
},
getSection: function(windowPos) {
var returnValue = null;
var windowHeight = Math.round(this.
$win.height() * this.config.scrollThreshold);
for(var section in
this.sections) { if((this.sections[section] - windowHeight) <
windowPos) { returnValue = section;
}
}
return returnValue; },
handleClick: function(e) { var self = this; var
$link = $(e.currentTarget); var $parent = $link.parent();
var newLoc = '#' + self.getHash($link);
if(!$parent.hasClass
(self.config.currentClass)) { //Start callback
if(self.config.begin) {
self.config.begin();
}
//Change the highlighted nav item
self.adjustNav(self, $parent);
//Removing the
auto-adjust on scroll self.unbindInterval();
//Scroll to the correct position self.scrollTo(newLoc,
function() { //Do we need to change the hash?
if(self.config.changeHash) {
window.location.hash = newLoc;
}
//Add the auto-adjust on scroll back in
self.bindInterval();
//End callback
if(self.config.end) {
self.config.end();
}
});
}
e.preventDefault(); },
scrollChange: function() {
var windowTop = this.$win.scrollTop();
var position =
this.getSection(windowTop); var $parent;
//If the
position is set if(position !== null) { $parent =
this.$elem.find('a[href$="#' + position + '"]').parent();
//If
it's not already the current section if(!$parent.hasClass
(this.config.currentClass)) { //Change the highlighted nav
item this.adjustNav(this, $parent);
//If there is a scrollChange callback if
(this.config.scrollChange) {
this.config.scrollChange($parent);
}
}
}
},
scrollTo: function(target,
callback) { var offset = $(target).offset().top;
$('html, body').animate({ scrollTop: offset
}, this.config.scrollSpeed, this.config.easing, callback);
},
unbindInterval: function() { clearInterval(this.t);
this.$win.unbind('scroll.onePageNav');
}
};
OnePageNav.defaults =
OnePageNav.prototype.defaults;
$.fn.onePageNav = function(options) { return
this.each(function() { new OnePageNav(this, options).init(); });
};
})( jQuery, window , document );