Hello Paresh Sen,
In one of the latest internal releases we have introduced a built-in GridViewToggleRowDetails column. You can simply add it as the first column of your grid and it will hook up to the row details automatically.
From then on, if you programmatically change the DetailsVisibility of the parent GridViewRow, the details will collapse and the toggle button will update its sign automatically.
I have prepared a small sample project to demonstrate this. You can use it as a base. I hope it helps.
Sincerely yours,
Ross
the Telerik team