Scroll to top folosind jQuery

Subiect: Scroll to top folosind jQuery Mar Mar 15, 2011 12:18 am

Acesta foloseste jQuery care face in asa fel incat cand dati click pe o imagine (sageata) pagina sa derula nu imediat, ci va aluneca
cum s-ar zice, pana ajunge la capatul paginii, iar cand ajungeti la
capatul pagini imaginea va disparea in ceata. O demonstratie aveti aici (dati in josul paginii pentru a vedea efectul).

Afisati acest cod:

Cod:: <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" lang="en" xml:lang="en">

<script type="text/javascript" src="http://ajax.googleapis.com/ajax/libs/jquery/1.3.2/jquery.min.js"></script>

Intrati in Start › Run › Si scrieti notepad

Copiati codul de mai jos si adaugati-l in notepad-ul deschis:

Cod:: //** jQuery Scroll to Top Control script- (c) Dynamic Drive DHTML code library: http://www.dynamicdrive.com.
//** Available/ usage terms at http://www.dynamicdrive.com (March 30th, 09')
//** v1.1 (April 7th, 09'):
//** 1) Adds ability to scroll to an absolute position (from top of page) or specific element on the page instead.
//** 2) Fixes scroll animation not working in Opera.

var scrolltotop={
//startline: Integer. Number of pixels from top of doc scrollbar is scrolled before showing control
//scrollto: Keyword (Integer, or "Scroll_to_Element_ID"). How far to scroll document up when control is clicked on (0=top).
setting: {startline:100, scrollto: 0, scrollduration:1000, fadeduration:[500, 100]},
controlHTML: '<img src="imagine.png" />', //HTML for control, which is auto wrapped in DIV w/ ID="topcontrol"
controlattrs: {offsetx:5, offsety:5}, //offset of control relative to right/ bottom of window corner
anchorkeyword: '#top', //Enter href value of HTML anchors on the page that should also act as "Scroll Up" links

state: {isvisible:false, shouldvisible:false},

scrollup:function(){
if (!this.cssfixedsupport) //if control is positioned using JavaScript
this.$control.css({opacity:0}) //hide control immediately after clicking it
var dest=isNaN(this.setting.scrollto)? this.setting.scrollto : parseInt(this.setting.scrollto)
if (typeof dest=="string" && jQuery('#'+dest).length==1) //check element set by string exists
dest=jQuery('#'+dest).offset().top
else
dest=0
this.$body.animate({scrollTop: dest}, this.setting.scrollduration);
},

keepfixed:function(){
var $window=jQuery(window)
var controlx=$window.scrollLeft() + $window.width() - this.$control.width() - this.controlattrs.offsetx
var controly=$window.scrollTop() + $window.height() - this.$control.height() - this.controlattrs.offsety
this.$control.css({left:controlx+'px', top:controly+'px'})
},

togglecontrol:function(){
var scrolltop=jQuery(window).scrollTop()
if (!this.cssfixedsupport)
this.keepfixed()
this.state.shouldvisible=(scrolltop>=this.setting.startline)? true : false
if (this.state.shouldvisible && !this.state.isvisible){
this.$control.stop().animate({opacity:1}, this.setting.fadeduration[0])
this.state.isvisible=true
}
else if (this.state.shouldvisible==false && this.state.isvisible){
this.$control.stop().animate({opacity:0}, this.setting.fadeduration[1])
this.state.isvisible=false
}
},

init:function(){
jQuery(document).ready(function($){
var mainobj=scrolltotop
var iebrws=document.all

mainobj.cssfixedsupport=!iebrws || iebrws &&
document.compatMode=="CSS1Compat" && window.XMLHttpRequest //not
IE or IE7+ browsers in standards mode
mainobj.$body=(window.opera)? (document.compatMode=="CSS1Compat"? $('html') : $('body')) : $('html,body')
mainobj.$control=$('<div id="topcontrol">'+mainobj.controlHTML+'</div>')

.css({position:mainobj.cssfixedsupport? 'fixed' : 'absolute',
bottom:mainobj.controlattrs.offsety,
right:mainobj.controlattrs.offsetx, opacity:0, cursor:'pointer'})
.attr({title:'Scroll Back to Top'})
.click(function(){mainobj.scrollup(); return false})
.appendTo('body')

if (document.all && !window.XMLHttpRequest &&
mainobj.$control.text()!='') //loose check for IE6 and below, plus
whether control contains any text

mainobj.$control.css({width:mainobj.$control.width()}) //IE6- seems to
require an explicit width on a DIV containing text
mainobj.togglecontrol()
$('a[href="' + mainobj.anchorkeyword +'"]').click(function(){
mainobj.scrollup()
return false
})
$(window).bind('scroll resize', function(e){
mainobj.togglecontrol()
})
})
}
}

scrolltotop.init()

Inlocuiti din cod imagine.png
cu link-ul imaginii pe care ati ales-o, salvati fisierul ca .js si
uploadati-l. Cei care doresc imaginea cu sageata folosita in exemplu:

Scroll to top folosind jQuery Arrow14

Daca nu stiti sa uploadati un fisier .js, cititi acest tutorial.

Apoi afisati urmatorul cod:

Cod:: <script type="text/javascript" src="scrolltopcontrol.js"></script>

Inlocuiti scrolltopcontrol.js cu link-ul fisierului .js pe care l-ati uploadat si am finalizat.

Sursa: http://www.dynamicdrive.com/ | Tradus de Wisdom