Regarding DHTMLX grid cell properties

I want to display three check boxes in on single cell.I have done it using clist.

In that i want to have one small pop up when user clicks in checkbox.

How i can acheive this??

You can modify code of existing excell, or create new one, where any functionality may be implemented in desired way.

In dhtmlxgrid_excell_clist.js you can locate next string

this is code which generate checkbox, you can add any onclick event handlers to it, to provide your custom functionality.