I saw some smart rendering examples are XML data format to use, smart rendering I want to use the JSON format , mygrid.load(url,“json”); how to use smart rendering 
The technique is the same.
In case of dynamic loading please, make sure that dhtmlxgrid_json.js is included to the page and have a look at the correct format of data:
docs.dhtmlx.com/doku.php?id=dhtm … at_details