javascript - iscroll is not working completely until inspect element is on -

i'm making chat box contains iscroll , dragging fine scroll bar not appearing when dialogues entered , when turn on inspect element works fine ,but when mores dialogues entered scroll bar doesn't change length , again turning on inspect element works fine .

html :

<div id="conversation" class="conversation "> <div id="scroller"> </div> </div> 

css :

.conversation { position:relative;  width: 100%; background: #a00; padding-top: 10px; overflow: auto; height: 205px; } #conversation{ overflow:auto; height: 205px; }  #scroller{ position: relative; background: #000; bottom: 10px; overflow: auto; }  

js :

 var myscroll; function loaded() { myscroll = new iscroll('conversation'); }  document.addeventlistener('touchmove', function (e) { e.preventdefault(); }, false);  document.addeventlistener('domcontentloaded', function () { settimeout(loaded, 200); },              false); 

help please :)