I think i almost found a solution, i just need to know another detail.

I added a client-side function to the checkbox from my previous post. When the box is checked i want to update the right cell in the datagrid.

<asp:CheckBox runat="server" OnClick="boxClicked(this);"/>

Here is my javascript function:

function boxClicked(checkbox) {
            var cbid = checkbox.id;
            var cblen=cbid.length
            var idnum = parseInt(cbid.substring(cblen - 2, cblen));

            var ssgrid = $find('<%= SestevalniStevec.ClientID %>');
            var row = ssgrid.get_rows().get_row(idnum);
            var cell = get_cell(2);
        }

But when i call get_cell, i get "Microsoft JScript runtime error: Object expected", does anybody know what could be causing this? I want to get a reference to my selected cell so i can set its value to true or false. I also tried get_cellByColumnKey("Popravek") and got the same result.

EDIT: never mind, i forgot to write row.get_cell. maybe i'll get it working soon and then i'll post what i did.

Now i have transferred some of the functionality from the code-behind to the aspx, now i have a list of columns like this:

<ig:BoundDataField Key="Naziv"><Header Text="Naziv" /></ig:BoundDataField>
<ig:BoundDataField key="Odčitek"><Header Text="Odčitek" /></ig:BoundDataField>
                                                    <ig:TemplateDataField Key="Popravek" Width="50px">
                                                        <HeaderTemplate>Popravek</HeaderTemplate>
                                                        <ItemTemplate>
                                                            <div style="text-align: center;">
                                                            <asp:CheckBox runat="server"/>
                                                        </ItemTemplate>
                                                    </ig:TemplateDataField>
<ig:BoundDataField Key="Količina"><Header Text="Količina" /></ig:BoundDataField>
<ig:BoundDataField key="Preračun"><Header Text="Preračun" /></ig:BoundDataField>

"Popravek " is the only column with a boolean value. All the other columns work properly, and Popravek shows a checkbox, but this checkbox is not linked to the actual data. Is there any way for me to bind it? Or maybe to handle the checkbox events with javascript?