RadGrid does not populate

[Anup]

Hi,
I am using 2 Stored Procedures to populate 2 different RadGrids. For RadGrid1, OnNeedDataSource event calls a handler function inside which a SP is executed and the data table is equated to RadGrid1.DataSource. Now, I want to populate RadGrid2 when a row is selected in RadGrid1. For this, OnRowSelected event of RadGrid1 is handled by a Javascript function that is extracting some specific cell values of the selected row and initiates an ajaxRequest() with argument string passed. I am using a RadAjaxManager which looks like :

<

telerik:RadAjaxManager ID="RadAjaxManager1" runat="server" OnAjaxRequest="RadAjaxManager1_OnAjaxRequest">

 <AjaxSettings>

 <telerik:AjaxSetting AjaxControlID="RadGrid1">

 <UpdatedControls>

 <telerik:AjaxUpdatedControl ControlID="RadGrid1" LoadingPanelID="RadAjaxLoadingPanel1" />

 

<telerik:AjaxUpdatedControl ControlID="RadGrid2" LoadingPanelID="RadAjaxLoadingPanel1" />

 </UpdatedControls>

 </telerik:AjaxSetting>

 </AjaxSettings>

 </telerik:RadAjaxManager>

 
In Code-Behind, I have a handler function RadAjaxManager1_OnAjaxRequest() for handling the ajax request. Inside RadAjaxManager1_OnAjaxRequest, I am passing on the arguments to execute an SP and equating the data table returned to RadGrid2.DataSource, as below :

protected

 

void RadAjaxManager1_OnAjaxRequest(object sender, AjaxRequestEventArgs e)

{

String argument = e.Argument;

String[] args = argument.Split("^".ToCharArray());

NameValueCollection parameters = new NameValueCollection();

parameters.Add("@par1", args[0]);

 parameters.Add("@par2", args[1]);

 parameters.Add("@par3", args[2]);

 RadGrid2.DataSource = obj.ExecuteSP("MySP", parameters);

 RadGrid2.Rebind();
}

The problem arises now, when I select a row in RadGrid1, I do not see any RadAjaxLoadingPanel being loaded. Moreover, the RadGrid2 does not populate. However, While debugging I am able to see that the rows are being returned(RadGrid2.DataSource.Rows.Count is greater than 0).

Thanks,
Anup

[Tsvetoslav]

Hi Anup,

It is the RadAjaxManager control that makes the ajax request - so RadAjaxManager should ajaxify the second grid. In other words, you need to following ajax setting:

<telerik:AjaxSetting AjaxControlID="RadAjaxManager1">
    <UpdatedControls>
        <telerik:AjaxUpdatedControl ControlID="RadGrid2" LoadingPanelID="rAjaxLoadingPanel"/>
    </UpdatedControls>
</telerik:AjaxSetting>

Hope it helps.
 
All the best,
Tsvetoslav
the Telerik team

[Anup]

Hi Tsvetoslav,

Thanks alot. This worked :)
But now, after the RadGrid2 gets populated, the selected row in RadGrid1 gets deselected automatically.

How to stop this automatic deselection?

Thanks...

[Tsvetoslav]

Hi Anup,

RadGrid does not automatically persist the selected state of its items. You need to do so programmatically as explained in the followign help topics:
http://www.telerik.com/help/aspnet-ajax/grid-persist-selected-rows-on-sorting.html
http://www.telerik.com/help/aspnet-ajax/grid-persist-selected-rows-client-sorting-paging-grouping-filtering.html


Greetings, Tsvetoslav
the Telerik team

[Anup]

Thanks Tsvetoslav,
I did try the steps described in these links earlier but ended up in another issue. I was able to restore the current selection but, RadGrid also persisted the last selection. I tried hard but could not resolve it.

Finally, I decided to put the code to execute SP and  equate it to RadGrid2 .DataSource in the OnSelectedIndexChanged event of RadGrid1 :)

Do let me know if this is a correct implementation.
Thanks again!!!

[Tsvetoslav]

Hi Anup,

Yes, it is correct. You just need one more step - to call RadGrid2's Rebind() method.

However, if you are using NeedDataSource for RadGrid2, the correct approach will be:

- in the SelectedIndexChanged event for RadGrid1, extract and keep in local variables any information you need for the population of RadGrid2; then call RadGrid2's Rebind() method.

- in the NeedDataSource event for RadGrid2, use the information kept from step1 to correctly call the stored procedure.
 
Greetings,
Tsvetoslav
the Telerik team