Sitecore MVC error: IDisplayMode

Yesterday I ran into the following error while setting up a MVC project for Sitecore 7.2

Method not found: ‘System.Web.WebPages.IDisplayMode System.Web.Mvc.ControllerContext.get_DisplayMode()’.

Description: An unhandled exception occurred.

Exception Details: System.MissingMethodException: Method not found: ‘System.Web.WebPages.IDisplayMode System.Web.Mvc.ControllerContext.get_DisplayMode()’.

Problem was very easily solved by removing the Microsoft.Web.Mvc.FixedDisplayModes.dll

The dll is an old legacy fix for MVC4 and it can safely be removed when working with MVC5.


Using strongly typed repeaters with Sitecore

Strongly typed repeaters has been around for a little while in .net now and I really like how it makes the front end code in my repeaters look less messy when I am using them in a Sitecore solution.

Consider the following snippet of code:

<asp:Repeater ID="repProductList" runat="server">
            <a href="<%# Sitecore.Links.LinkManager.GetItemUrl(Container.DataItem as Sitecore.Data.Items.Item) %>">
                <sc:Text ID="header" Field="Header" Item="<%# Container.DataItem as Sitecore.Data.Items.Item %>" runat="server" />
        <sc:Text ID="content" Field="Product Overview" Item="<%# Container.DataItem as Sitecore.Data.Items.Item %>" runat="server" />

In this pretty simple example I am only casting the Container.DataItem to a Sitecore item.
Now do the same thing with a typed repeater, note the “ItemType” parameter in the repeater tag:

<asp:Repeater ID="repProductList" ItemType="Sitecore.Data.Items.Item" runat="server">
            <a href="<%# Sitecore.Links.LinkManager.GetItemUrl(Item) %>">
                <sc:Text ID="header" Field="Header" Item="<%# Item %>" runat="server" />
        <sc:Text ID="content" Field="Product Overview" Item="<%# Item %>" runat="server" />
  • No more casting of the repeater datasource item to a Sitecore item. (Costly?)
  • No need for handling ItemDataBound events where you iterate to find your controls and then set the datasource
  • You have access to the whole Item object in the repeater and can get any properties you’ll like

The same thing goes when we are building a repeater returning results from a search using Sitecore Search API, you can set your repeaters ItemType to the generic SearchResultItem provided by Sitecore or your own derived class. More on that in another post.


Responsive Web Design done better with Sitecore Device detection

Responsive Web Design is the new black and there are a ton of ready frameworks and blog posts out there to help you on your way. Just as Lauren Hightower writes in this post the traditional way of doing mobile design in Sitecore is by developing roughly two sets of renderings and layouts and combining these in separate devices in Sitecore. This takes up a lot of time and it gets even harder when you create multiple devices for different smartphones, tablets and other screens. Responsive design targets all of this in a clean way letting you rely on one single layout for almost all devices.

Responsive design usually works by adding CSS and JavaScript to a page. These scripts will calculate the screen width and hide elements that are too big to fit according to the design rules. There are however some things to consider: Sending a full payload of images for a JQuery slider, that is not even shown on a small screen, might not be the best of ideas when the user is on a slow mobile connection . And that nice high resolution jpeg used as background image might take some time to download for anyone that is not on a laptop with a strong WiFi or cable connection. What if you need a separate menu structure for all mobile visitors targeting content more suited for mobile users on the run?

Sitecore off course has a solution to the above problems:

  • Sitecore rules on layouts
  • Dynamic image scaling

Setting rules on layouts

As I wrote above, the normal way of handling browsers with different screen sizes in Sitecore is by separating them using Devices. When developing with Responsive Design there is actually no need for this. Instead we can enhance the experience for the mobile user by setting rules on the renderings for the page.

Using the MobileDeviceDetector you can utilize the WURFL framework. The MDD add a set of rules to the Sitecore Rules Engine that let’s you personalize on the features of the visiting device. In the below screenshot we change the “HeroSlider” to a “HeroImage” for all visitors using mobile devices.

Change Rendering For Mobile Device

Set a different rendering when on a mobile device

Dynamic image scaling

As all Sitecore developers know, Sitecore automatically scales all images on demand. Add a querystring parameter to the image url depending on the screen width and this will make the Sitecore server scale the image to correct size before sending it to the client. More about Sitecore Image Parameters in this blog post by John West.

A couple of days ago Scott Mulligan (@scottmulligan) released his module Sitecore Adaptive Images available on the Sitecore Marketplace. Sitecore Adaptive Images is a cool add on that helps you deliver images to your visitors in a size that is adapted to their resolution.

By using responsive design, layout rules and dynamic image scaling your next Sitecore project will rock!


New features in Sitecore 6.6 – Webinar

The other day I hosted a webinar going through the latest features of Sitecore 6.6 together with the two new modules Sitecore Item Web API and Sitecore Mobile SDK.

New features of Sitecore 6.6 are:

  • MVC – Sitecore now supports mixed utilization of both Web Forms and MVC development.
  • Device Simulators – ability to simulate other devices straight from the Page Editor.
  • Page Preview – lets you preview your pages exactly as they are rendered on the actual device.
  • Engagement Automation enhancements
  • Dictionary enhancements – now supports multiple dictionaries, fallback and inheritance.
  • Recycle Bin and Version Archive changes
  • Executive Dashboard updates – more filtering, better search.
  • Page Editor enhancements – a lot of new features previously only available through Content Editor.
  • Lucene upgrade – 2.9.4
  • SQL Server mirroring

Sitecore Mobile SDK is a new flexible framework that lets the developer build native mobile applications with the ability to read, create and update content in Sitecore.

In order to support Sitecore Mobile SDK, Sitecore released the Sitecore Item Web API. This is a REST-like API that returns JSON. It can be used to integrate Sitecore with f.ex. Java-based systems, build fast loading JQUERY menues or support mobile applications on any platform.

The embedded video is in Swedish, it starts with new Sitecore features and after 27 minutes I start talking about Item Web API and Mobile SDK. Enjoy!


Dynamic anchorlinks in Sitecore

In a current project we have developed a solution with pages that are compiled from several different Sitecore items. This might not seem like a strange thing since allmost all pages served by any CMS is a compilation of items one way or another.

The thing here is that we want all pages to be as modular as possible, giving the editors an easy way to add various functionality over the different pages. Instead of creating a big set of different templates serving every need we instead use a structure with one item that represents the actual page and subitems that add modular content to that page. Content can be shown as one single scrollable page or separated in tabs using JQuery. I hope to be able to elaborate on this in a future post.

Anyway, no matter if the content should be shown in one page, in tabs or in any other way we had to be able to link to the different subitems directly. As I prefer standard HTML using anchors seemed the way to go, anchors works fine in a plain scrollable page but it could also be used in JQuery tabs.

Standard Sitecore behaviour for links would be that if I would link to a subitem of a page the URL for that link would read “http://hostname/page/subitemfolder/subitem”, since the subitem has no layout Sitecore would return an error page. The link should instead read “http://hostname/page#subitem”, Since we are talking Sitecore, this if fairly easy to accomplish.

We override the linkManager section in web.config (preferably by using an include file).

<linkManager defaultProvider="sitecore">
        <!--<add name="sitecore" type="Sitecore.Links.LinkProvider, Sitecore.Kernel" addAspxExtension="true" alwaysIncludeServerUrl="false" encodeNames="true" languageEmbedding="asNeeded" languageLocation="filePath" shortenUrls="true" useDisplayName="false"/>-->
        <add name="sitecore" type="Sitecore64.LinkProvider, Sitecore64" addAspxExtension="true" alwaysIncludeServerUrl="false" encodeNames="true" languageEmbedding="asNeeded" languageLocation="filePath" shortenUrls="true" useDisplayName="false"/>

Then we override the LinkProvider as below.

using Sitecore.Data;
using Sitecore.Data.Managers;
using Sitecore.Data.Templates;

namespace Sitecore64
    public class LinkProvider : Sitecore.Links.LinkProvider
        public override string GetItemUrl(Sitecore.Data.Items.Item item, Sitecore.Links.UrlOptions options)
            Template template = TemplateManager.GetTemplate(item);
                string url = base.GetItemUrl(item.Parent.Parent, options) + "#" + item.DisplayName;
                return url;
            return base.GetItemUrl(item, options);

One thing to note here is that all subitems use a common base template to define that they are actual subitems and should be addressed using a hashtag and pointing to a grandparent.

Off course you would need to add logic to verify that parent elements exists and are based on the correct template and so on.


Using TortoiseMerge when upgrading Sitecore

Upgrading Sitecore has become a lot easier since the release of Sitecore 6.0.1 featuring the Update Installation Wizard.
With the UIW we get a clear overview of what files will be updated or removed, also the affected files are copied to a separate directory under the temp-folder where it is available to us should we need them. When examining the folders further there also seems to be some kind of rollback feature but I have yet to find the documentation for this, so far I have never needed to rollback an upgrade though (knock on wood).

Upgrading Sitecore is as easy as one, two, three… until you get to the web.config

Even after introducing the include-files for web.config it still consists of 3000+ lines of code. Often there are changes made here and there by developers overloading Sitecore functionality or optimizing caching and such.

Today I started to upgrade a solution from Sitecore 6.2.0 rev.091012 to 6.3.0 rev.100716, i was following the very clear instructions at SDN. Basically it is done by first changing a few rows in web.config then running UIW (around 5400 items and files affected) then doing a lot of more changes in web.config. I kind of gave up when I opened the last page of changes and my right-hand scroll quickly was shrunk to about 1/10 of the screen height.

And this was only the developing environment; I also had to do the stage and live servers with their specific web.config’s.

There should be some kind of tool for merging code-filled files… well how about TortoiseMerge? I use it all the time when my colleagues and I make changes to the same files and my commit to subversion fails. I did not know however that I could feed the program with any files I wanted. Well IT JUST WORKS!

Here’s how I did it:

First I downloaded the complete web.config for the version I was upgrading to.

Then opening TortoiseMerge without any parameters brings up this dialog

TortoiseMerge Open File Dialog

TortoiseMerge Open File Dialog

Given the fact that most of the changes was made to the new web.config I used this one as “My File” and my old web.config as “Their file”. I didn’t bother using a base file. I clicked “Ok” and started merging my changes with the new file. Basically everything marked red to the left is worth having a closer look at.

Merging files

Merging files

Then I saved the file and moved it to the web-directory restarted IIS and it worked right away.

This will save me a lot of the frustration and time when upgrading Sitecore solutions in the future.

Link to TortoiseSVN