ASP.NET 3.5 GridView - row editing - dynamic binding to a DropDownList
- by marc_s
This is driving me crazy :-)
I'm trying to get a ASP.NET 3.5 GridView to show a selected value as string when being displayed, and to show a DropDownList to allow me to pick a value from a given list of options when being edited. Seems simple enough?
My gridview looks like this (simplified):
<asp:GridView ID="grvSecondaryLocations" runat="server"
DataKeyNames="ID" OnInit="grvSecondaryLocations_Init"
OnRowCommand="grvSecondaryLocations_RowCommand"
OnRowCancelingEdit="grvSecondaryLocations_RowCancelingEdit"
OnRowDeleting="grvSecondaryLocations_RowDeleting"
OnRowEditing="grvSecondaryLocations_RowEditing"
OnRowUpdating="grvSecondaryLocations_RowUpdating" >
<Columns>
<asp:TemplateField>
<ItemTemplate>
<asp:Label ID="lblPbxTypeCaption" runat="server"
Text='<%# Eval("PBXTypeCaptionValue") %>' />
</ItemTemplate>
<EditItemTemplate>
<asp:DropDownList ID="ddlPBXTypeNS" runat="server"
Width="200px"
DataTextField="CaptionValue"
DataValueField="OID" />
</EditItemTemplate>
</asp:TemplateField>
</asp:GridView>
The grid gets displayed OK when not in editing mode - the selected PBX type shows its value in the asp:Label control. No surprise there.
I load the list of values for the DropDownList into a local member called _pbxTypes in the OnLoad event of the form. I verified this - it works, the values are there.
Now my challenge is: when the grid goes into editing mode for a particular row, I need to bind the list of PBX's stored in _pbxTypes.
Simple enough, I thought - just grab the drop down list object in the RowEditing event and attach the list:
protected void grvSecondaryLocations_RowEditing(object sender, GridViewEditEventArgs e)
{
grvSecondaryLocations.EditIndex = e.NewEditIndex;
GridViewRow editingRow = grvSecondaryLocations.Rows[e.NewEditIndex];
DropDownList ddlPbx = (editingRow.FindControl("ddlPBXTypeNS") as DropDownList);
if (ddlPbx != null)
{
ddlPbx.DataSource = _pbxTypes;
ddlPbx.DataBind();
}
.... (more stuff)
}
Trouble is - I never get anything back from the FindControl call - seems like the ddlPBXTypeNS doesn't exist (or can't be found).
What am I missing?? Must be something really stupid.... but so far, all my Googling, reading up on GridView controls, and asking buddies hasn't helped.
Who can spot the missing link? ;-)
Marc
