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Facebook sidebar recreation.(I simply don't know its name...) Using RequireJS and jQuery, but you can easily grab useful parts!
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/** | |
* @file UI.sidebar | |
* Facebook sidebar recreation | |
*/ | |
define(["jquery"],function($){ | |
//from http://stackoverflow.com/a/17961266/2281355 | |
var isAndroid = navigator.userAgent.indexOf('Android') >= 0; | |
var webkitVer = parseInt((/WebKit\/([0-9]+)/.exec(navigator.appVersion) || 0)[1],10) || void 0; | |
var isNativeAndroid = webkitVer <= 534 || ( isAndroid && navigator.vendor.indexOf('Google') == 0 ); | |
//your sidebar, specify it below | |
var $sidebar=$("#sidebar-affix"); | |
//your sidebar need to be wrapped by a block element. | |
//this is useful when you are using grid system since the snippet | |
// will keep the dimension(height/width) for you. | |
var $parent =$sidebar.parent(); | |
//you can set for fixed navbar | |
var offset=60; | |
//you can set custom padding of the sidebar. | |
//the sidebar will apply next beheavior to avoid | |
// these regions just like bootstrap affix. | |
var top =0, | |
bottom=$("#footer").outerHeight(true); | |
var isFirst=true; | |
var heightDelta=0; | |
//cache its dimension | |
var reMeasure=function(){ | |
if(isNativeAndroid)return; | |
var sbw=$parent.width(); | |
var sbh=$sidebar.height(); | |
var pos=$sidebar.css("position"); | |
//Sometimes inner margin collapses, causing wrong | |
// height calculation. | |
var needDelta=(pos=="static"||pos=="relative"); | |
if(sbw!=$sidebar.width()){ | |
$sidebar.css("width",sbw); | |
//console.log("w set"); | |
} | |
if($parent.css("position")=="fixed"){ | |
//remove inline css | |
//taken over by pure css classes | |
$sidebar.css("top",""); | |
$parent.css("height",""); | |
return; | |
} | |
var ph=$parent.height(); | |
//for comparing their height | |
if(needDelta) | |
sbh+=heightDelta; | |
if(isFirst){ | |
//ensure that it is absolute | |
// or we will miss the margin of | |
// the inner elements | |
//also calculate delta | |
var sh1=$sidebar.height(); | |
$sidebar.css("position","absolute"); | |
$parent.css("height",$sidebar.height()); | |
heightDelta=$sidebar.height()-sh1; | |
$sidebar.css("position","relative"); | |
//console.log("h set first",heightDelta); | |
isFirst=false; | |
}else if(sbh!=ph){ | |
//console.log("h set",sbh,bef); | |
$parent.css("height",sbh); | |
} | |
}; | |
var prevScr=-1; | |
var w=$(window); | |
var sidebarHandler=function(){ | |
if(isNativeAndroid) | |
return; | |
//mobile device | |
if($parent.css("position")=="fixed") | |
return; | |
var isFixed=$sidebar.css("position")=="fixed"; | |
var scr=w.scrollTop(); | |
var ot=$sidebar.offset().top; | |
var pt=$parent.offset().top; | |
var wh=w.height(); | |
var ph=$(document).height(); | |
var oh=$parent.outerHeight(true); | |
var delta=scr-prevScr; | |
if(scr<top){ | |
//avoid top | |
if(isFixed) | |
$sidebar.css({position:"absolute",top:top}); | |
}else if(scr+wh>ph-bottom){ | |
//avoid bottom | |
if(isFixed){ | |
$sidebar.css({position:"absolute",top:ph-oh-offset-bottom}); | |
} | |
}else if(delta<0){ | |
//scroll upward | |
if(isFixed&&ot-scr!=offset){ | |
$sidebar.css({position:"absolute",top:ot-offset}); | |
}else if(!isFixed&&ot-offset>scr){ | |
$sidebar.css({position:"fixed",top:offset}); | |
} | |
}else{ | |
//scroll downward | |
if(isFixed&&(ot-scr==offset||ot+oh!=scr+wh)){ | |
if(wh<oh){ | |
$sidebar.css({position:"absolute",top:ot-pt}); | |
} | |
}else if(!isFixed&&ot+oh<scr+wh){ | |
$sidebar.css({position:"fixed",top:wh<oh?wh-oh:offset}); | |
} | |
} | |
reMeasure(); | |
prevScr=scr; | |
}; | |
$(reMeasure);//reMeasure immediately | |
//delegate | |
w.on("resize",reMeasure); | |
w.on("scroll",sidebarHandler); | |
return $sidebar; | |
}); |
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