This is the first post in a series on Web Parts Connections. This spring I had a series on Web Part Properties that I think was very successful, they got some good comments and feedback and they get a lot of hits from search engines. Please help me out and evolve this new series of posts with some feedback and questions.
What is Web Parts Connections?
Web Parts Connections allows you to connect the Web Part server controls so that they can exchange information. Web Parts can either be a consumer and/or a provider. Once you connect a consumer with a provider the consumer starts receiving data from the provider, all this is done on the server side. Web Parts can be constructed in such way that it can have several consumer and provider connection-points, i.e.it can consume or provide information from several different sources. A provider connection-point can have several consumers but a consumer connection-point can have only one provider.
The image, to the right, illustrates in the top; one Web Part connected to another. The middle sample shows how one provider Web Part is connected to two consumer Web Parts. The sample in the bottom shows a consumer Web Part that have two consumer end-points that are connected to two different provider Web Parts.
Note: Web Parts Connections are a part of the ASP.NET 2.0 framework
Why Connecting Web Parts?
When you connect Web Parts you enhance the experience for the user. You can for example have one Web Part containing a list of items and let that one act as a provider and then have a consumer Web Part that shows detailed information of the item selected in the provider Web Parts.
In SharePoint most of the default Web Parts are either consumers or providers. For example, with some easy clicks in the interface you can connect lists and make one a consumer and the other provider.
The image above shows two custom lists that are connected. The Regions list contains the names of the regions, used in the Sales list. With this simple action we have built a Filter Web Part to filter our Sales list. More about Filter Web Parts later on in the series. The left image shows how you make the actual connection and the image to the right shows you how you can filter the Sales list using the radio buttons on the Regions list.
I've been working a lot building dashboards and applications for BI-solutions and similar. Using connected Web Parts have both made the end-user experience a whole lot better (and more good looking) as well as the development of the dashboards.
This was an introduction to Web Parts Connections, the next part will be up in a couple of days.
Until next time.
SharePoint Saturday Copenhagen is over after an awesome Saturday in Copenhagen. Thank you all organizers, attendees, speakers and sponsors, I had a blast. I will definitely attend more SharePoint Saturdays when I can. These kind of events really are special; everyone attending are there because they really love working with SharePoint, on a Saturday, when the sun is shining outside, for free…
Until next time…
If you have been installing SharePoint you have probably also seen and fixed the DCOM 10016 error. This error occurs in the event log when the SharePoint service accounts doesn't have the necessary permissions (Local Activation to the IIS WAMREG admin service). Your farm will still function, but your event log will be cluttered.
On a Windows Server 2003 or Windows Server 2008 machine you would just fire up the dcomcnfg utility (with elevated privileges) and enable Local Activation for your domain account.
But for Windows Server 2008 R2 (and Windows 7, since they share the same core) you cannot do this, the property dialog is all disabled due to permission restrictions. It doesn't matter if you are logged in as an administrator or using elevated privileges. The change is probably due to some new security improvements.
The reason for it being disabled is that this dialog is mapped to a key in the registry which the Trusted Installer is owner of and everyone else only has read permissions. The key used by the IIS WAMREG admin is:
Image on the left shows the default permissions for Windows Server 2008 R2 and on the right the default settings for Windows Server 2008.
To be able to change the Launch and Activation Permissions with dcomcnfg you have to change the ownership if this key. Start the registry editor (regedit), find the key, click Advanced in the Permissions dialog of this key and select the Owner tab. Now change the owner of the key to the administrators group for example, then set full control to the administrators group. Make sure not to change the permissions for the TrustedInstaller.
Now you have to restart the dcomcnfg application and once find the IIS WAMREG application and then set the Launch and Activation settings that you need to get rid of the DCOM 10016 error.
WARNING: Changing the registry may seriously damage your server. All is on your own risk!
SharePoint Saturday is a free informational and educational event that has been held over-there in US several times with a huge success the last year and it is now coming to Europe and Copenhagen, Denmark to be more specific. A SharePoint Saturday is an event for anyone interested in SharePoint and who like to meet similar-minded people and listen to SharePoint professionals and celebrities.
I'm going to be there - it will be a blast! I will do a presentation called SharePoint Online and Windows Azure - better together! And I will of course listen to all the other really cool people showing up such as SharePoint MVP's and gurus.
If you would like to come, did I mention it's free, then head on over to http://www.sharepointsaturday.org/copenhagen/ and register yourself! I look forward to meeting you all!