Check box in header of List grid

[vgattani]

I am using a simple ListGrid, below is the code

isc.ListGrid.create({
ID: "assignedList",
autoFetchData: true,
alternateRecordStyles: true,
canResizeFields: false,
selectionAppearance: "checkbox",
selectionProperty: "is_supervisor",
canEdit: true,
showSelectedStyle: false,
canAutoFitFields:false,
fields: [
{
name: "agent_name",
title: "supervisor",
type: "text",
width: "40%",
canEdit: false,
align: "center",
showDefaultContextMenu:false
}, {
name: "is_supervisor",
title: "supervise",
type: "boolean",
showDefaultContextMenu:false

}, {
name: "allow_start_stop_campaign",
title: "Allow Start",
type: "boolean",
showDefaultContextMenu:false,
}
],
data: getData()
});


2nd and 3rd column of this grid are of type boolean i.e. check box, how can I add a check box in the header of these columns in order to get functionality like "Check All" & "Un-Check All".

I saw some smartclient examples , they have the example where check box is in very first column but I want it in 2 columns. Also there must be a provision so that I can add "check box" in header along with the header text.