Binding Images to asp:repeater with Fluent API

Posted by Community Admin on 09-Dec-2010 00:00

I wanted to see how I could implement a portfolio gallery using jQuery. I was thinking that I can take a repeater and generate all the markup that I will need for the jQuery and use the API to pull the data for me. I am trying to emulate some of the code in the NewsRotator widget example, but an running into trouble with an "Object reference not set to an instance of an object" error.

1.) I created a user control.
2.) I registered the user control
3.) I added some test markup and code behind and am getting the error.
Here is my user control markup

<asp:Repeater ID="PortfolioRepeater" runat="server">

<HeaderTemplate><ul></HeaderTemplate>

<ItemTemplate>

<li><asp:Image ID="PortfolioImage" runat="server" /></li>

</ItemTemplate>

<FooterTemplate></ul></FooterTemplate>

</asp:Repeater>

Here is my user control code behind

using System;

using System.Collections.Generic;

using System.Linq;

using System.Web;

using System.Web.UI;

using System.Web.UI.WebControls;

using Telerik.Sitefinity;

using Telerik.Sitefinity.GenericContent.Model;

using System.ComponentModel;

namespace SitefinityWebApp.UserControls

public partial class CustomPortfolio : System.Web.UI.UserControl

protected void Page_Load(object sender, EventArgs e)

PortfolioRepeater.DataSource = App.WorkWith().Images().Get().ToList().Where(i => i.Parent.Title == "Portfolio" &&

i.Status == ContentLifecycleStatus.Live);

PortfolioRepeater.ItemDataBound += new RepeaterItemEventHandler(PortfolioRepeater_ItemDataBound);

PortfolioRepeater.DataBind();

void PortfolioRepeater_ItemDataBound(object sender, RepeaterItemEventArgs e)

var image = e.Item.FindControl("PortfolioImage") as Image;

Telerik.Sitefinity.Libraries.Model.Image portImage =

(Telerik.Sitefinity.Libraries.Model.Image)TypeDescriptor.GetProperties(e.Item.DataItem)["i"].GetValue(e.Item.DataItem);

if (image != null) image.ImageUrl = portImage.MediaUrl;

I am pretty sure my problem is in the ItemDataBound event where I am creating the portImage object. I am guessing I need something else in place of the "i" for this line I am pretty sure my problem is in the ItemDataBound event where I am creating the portImage object. I am guessing I need something else in place of the "i" for this line.

(Telerik.Sitefinity.Libraries.Model.Image)TypeDescriptor.GetProperties(e.Item.DataItem)["i"].GetValue(e.Item.DataItem);

I am very new to the API so suggestions on what I am trying to do or a better approach are welcome.

Thanks

Posted by Community Admin on 09-Dec-2010 00:00

Hi Stacey,

You are getting the error, because you are using an object that is "null" in the current context. You can get the image directly from the data item

void repeater_ItemDataBound(object sender, RepeaterItemEventArgs e)

// check whether you are in item template of the repater

var image = e.Item.DataItem as Telerik.Sitefinity.Libraries.Model.Image;

Best wishes,
Ivan Dimitrov
the Telerik team

Check out Telerik Trainer, the state of the art learning tool for Telerik products.

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