textBox Lose focus and entered value on nested Gridview

I have two nested Gridview that parent is for Posts and Child is for Comments, i want to update Post and Comments with a Time Interval so Im using an asp.net Timer, my problem is a TextBox that is in First Gridview lose focus when timer Tick, i Searched the web a lot, Possible solution was the put textbox out of UpdatePanel but in this situation i cant put out the textBox. please help me here is my code

<asp:ScriptManager ID="ScriptManager1" runat="server"></asp:ScriptManager> <asp:Timer ID="Timer1" Interval="10000" OnTick="Timer1_Tick" runat="server"></asp:Timer> <asp:UpdatePanel ID="UpdatePanel1" UpdateMode="Conditional" runat="server"> <Triggers> <asp:AsyncPostBackTrigger ControlID="Timer1" EventName="Tick" /> </Triggers> &l ...