var scrollButtonCache={
_count:0,
_idPrefix:"-scroll-button-cache-",
getId:function(){
return this._idPrefix+this._count++;
},
remove:function(o){
delete this[o.id];
}
};
function ScrollButton(oEl,oScrollContainer,nDir){
this.htmlElement=oEl;
this.scrollContainer=oScrollContainer;
this.dir=nDir;
this.id=scrollButtonCache.getId();
scrollButtonCache[this.id]=this;
this.makeEventListeners();
this.attachEvents();
}
ScrollButton.scrollIntervalPause=100;
ScrollButton.scrollAmount=18;
ScrollButton.prototype.startScroll=function(){
this._interval=window.setInterval(
"ScrollButton.eventListeners.oninterval(\""+this.id+"\")",
ScrollButton.scrollIntervalPause);
};
ScrollButton.prototype.endScroll=function(){
if(this._interval!=null){
window.clearInterval(this._interval);
delete this._interval;
}
};
ScrollButton.prototype.makeEventListeners=function(){
if(this.eventListeners!=null)
return;
this.eventListeners={
onmouseover:new Function("ScrollButton.eventListeners.onmouseover(\""+this.id+"\")"),
onmouseout:new Function("ScrollButton.eventListeners.onmouseout(\""+this.id+"\")"),
onunload:new Function("ScrollButton.eventListeners.onunload(\""+this.id+"\")")
};
};
ScrollButton.prototype.attachEvents=function(){
if(this.eventListeners==null)
return;
this.htmlElement.attachEvent("onmouseover",this.eventListeners.onmouseover);
this.htmlElement.attachEvent("onmouseout",this.eventListeners.onmouseout);
window.attachEvent("onunload",this.eventListeners.onunload);
};
ScrollButton.prototype.detachEvents=function(){
if(this.eventListeners==null)
return;
this.htmlElement.detachEvent("onmouseover",this.eventListeners.onmouseover);
this.htmlElement.detachEvent("onmouseout",this.eventListeners.onmouseout);
window.detachEvent("onunload",this.eventListeners.onunload);
};
ScrollButton.prototype.destroy=function(){
this.endScroll();
this.detachEvents();
this.htmlElement=null;
this.scrollContainer=null;
this.eventListeners=null;
scrollButtonCache.remove(this);
};
ScrollButton.eventListeners={
onmouseover:function(id){
scrollButtonCache[id].startScroll();
},
onmouseout:function(id){
scrollButtonCache[id].endScroll();
},
oninterval:function(id){
var oThis=scrollButtonCache[id];
switch(oThis.dir){
case 8:
oThis.scrollContainer.scrollTop-=ScrollButton.scrollAmount;
break;
case 2:
oThis.scrollContainer.scrollTop+=ScrollButton.scrollAmount;
break;
case 4:
oThis.scrollContainer.scrollLeft-=ScrollButton.scrollAmount;
break;
case 6:
oThis.scrollContainer.scrollLeft+=ScrollButton.scrollAmount;
break;
}
},
onunload:function(id){
scrollButtonCache[id].destroy();
}
};