Hi Ajay,
You can use aura:doneRendering for this. This event is automatically fired if no more components need to be rendered or rerendered due to any attribute value changes. The aura:doneRendering event is handled by a client-side controller. A component can have only one <aura:handler> tag to handle this event.
<aura:handler event=”aura:doneRendering” action=”{!c.doneRendering}”/>
Hope this helps you.