Silverlight 4: Nested DataGrid for Master-Details Scenarios

The Silverlight DataGrid is a very commonly used control for displaying huge amounts of data. Similarly to save screen space and display Master-Details scenarios, a Nested DataGrid is recommended.

In Silverlight, the DataGrid provides ‘RowDetailsTemplate’, using ‘additional details’ of a DataGrid row can be viewed. DataGrid RowDetailsTemplate accepts DataTemplate as its input and in the DataTemplate, we can put any other control like a DataTemplate for ItemsControls. In this article, I have shown a demonstration for the same:

Step 1: Open VS2010 and create a Silverlight application project. Name it as ‘SL4_Master_Details_DataGrid’. In this project, add a class file and name it as DataClasses.cs. Write the following code in it:

silverlight-nested-grid-source

The above class file defines classes for Order and Customer information. It also defines a class for storing Customer-Order details using CustomerCollection class. In a realistic scenario, you can make use of a WCF DataService or WCF Service returning Customer-Order details using a join query.

Now the challenge over here is to display this related data (nested data). In a typical UI, we could have created a ListBox with Customer Details and a DataGrid for displaying Order details. However this could utilize a lot of screen space and we would need to manage two separate controls – first we’d need to write code for data selection in the ListBox and then code to display child records in DataGrid, using some filter on the collection. But in Silverlight, using the RowDetailsTemplate, we can easily have a nested child DataGrid for each DataGrid row, for the parent.

Step 2: In the MainPage.Xaml write the following Xaml code:

silverlight-nested-datagrid-design

The above xaml code defines an instance of the CustomerCollection class in the resources of the UserControl. This instance is further bound with the Grid named LayoutRoot. Here are the important things to observe about the DataGrid, in the XAML code shown above:
  • The HeaderVisibility property of the DataGrid is set to ‘All’. This will display DataGrid Row headers along with column headers. This helps the user to select the row for which the details are to be viewed.
  • In the RowDetailsTemplate of the parent DataGrid, the child DataGrid is added, which is bound with the ‘Orders’ collection from the source.
Step 3: Run the application and click on the header of the row (extreme left). The following result will be displayed:

Silverlight Nested DataGrid

As seen above, the order details are displayed in the child DataGrid for the CustomerId 101.

Where can a Nested DataGrid be useful?

One practical example where this can be useful is if you are developing a Hospital Management System where the UI contains Doctor Details in a Tabular UI format. Now the end-user demands that the details of all patients for a doctor must be displayed immediately in Tabular format, whenever a doctor is selected in the Grid.

Download the source code




About The Author

Mahesh Sabnis is a Microsoft MVP having over 18 years of experience in IT education and development. He is a Microsoft Certified Trainer (MCT) since 2005 and has conducted various Corporate Training programs for .NET Technologies (all versions). He also blogs regularly at DotNetCurry.com. Follow him on twitter @maheshdotnet

2 comments:

Anonymous said...

Nice article but if this thing needs to be done in MVVM pattern will it work because as far as I have tried to make it work in MVVM pattern I have to define inner datagrid datacontext explicitly by mentioning "Binding={PropertyName,Source={StaticResource ViewModelKey}}" and this prevents me to declare my ViewModel as singleton which I want to retain.

Jason Smith said...

Hi Mahesh,

i am quite new to silverlight ( I come from a strong ASP.NET environment) and I must say i really like your examples i am working through most of the examples shown here:
http://www.dotnetcurry.com/ShowArticle.aspx?ID=735

and i see there is a lot created by you. Thank you for the time in creating these they are extremely easy to follow and learn XAML while doing them.