Prism Framework provides a very good solution for creating Modular applications in Silverlight.

First of we need to download Prism Framework from the Microsoft site

http://www.microsoft.com/download/en/details.aspx?id=4922.

The dlls would be downloaded as shown below:

dll in silverlight

I guess it would help if one has bit of understanding of how MEF works . Since that would make life easier.

Well lets start. Here I would demonstrate a simple working example of Prism Implementation.

Create a new Silverlight Library Project and named it as FirstHello.

Just add a view First.xaml.

<Grid x:Name="LayoutRoot" Background="White">
 <TextBlock Text="HelloWorld" FontSize="26" HorizontalAlignment="Center" VerticalAlignment="Center" />
 </Grid>
Create a new Module.
public class Module : IModule
 {
#region IModule Members

private IRegionManager regionManager;
IUnityContainer container;
public void Initialize()
{
if (this.regionManager.Regions.ContainsRegionWithName("FirstHello"))
{
this.regionManager.Regions["FirstHello"].Add(this.container.Resolve<First>());
}
}

public Module(IRegionManager regionManager, IUnityContainer container)
{
this.container = container;
this.regionManager = regionManager;
}
#endregion
}
The Module implements the Imodule Interface.

namespace Microsoft.Practices.Prism.Modularity
{
// Summary:
 // Defines the contract for the modules deployed in the application.
 public interface IModule
 {
// Summary:
 // Notifies the module that it has be initialized.
 void Initialize();
}
}

Similarly lets add a another Silverlight library project.

Second.xaml is the View.

<UserControl x:Class="SecondHello.View.Second"
 xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
 xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
 xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
 xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
 mc:Ignorable="d"
 d:DesignHeight="300" d:DesignWidth="400">
<Grid x:Name="LayoutRoot" Background="White">
 <TextBlock Text="GreetingWorld" FontSize="26" HorizontalAlignment="Center" VerticalAlignment="Center" />
 </Grid>
</UserControl>

The next Module looks as:

public class Module1 : IModule
 {
 #region IModule Members
private IRegionManager regionManager;
IUnityContainer container;
public void Initialize()
{
if (this.regionManager.Regions.ContainsRegionWithName("SecondHello"))
{
this.regionManager.Regions["SecondHello"].Add(this.container.Resolve<Second>());
}
}

public Module1(IRegionManager regionManager, IUnityContainer container)
{
this.container = container;
this.regionManager = regionManager;
}
#endregion
}

Let us create a new Silverlight Project SLPrismPart1.

Lets Create a Bootstrapper.

 public class Bootstrapper : UnityBootstrapper
 {
protected override DependencyObject CreateShell()
{
Shell shell = new Shell();
Application.Current.RootVisual = shell;
return shell;
}
protected override IModuleCatalog CreateModuleCatalog()
{
ModuleCatalog modules = new ModuleCatalog();
modules.AddModule(typeof(FirstHello.Module));
modules.AddModule(typeof(SecondHello.Module1));
return modules;
}
}
The Bootstrapper class extends the UnityBootstrapper class. The UnityBootstrapper class looks as below:

class in silverlight

The Bootstrapper class looks as follows:

 public class Bootstrapper : UnityBootstrapper
 {
protected override DependencyObject CreateShell()
{
Shell shell = new Shell();
Application.Current.RootVisual = shell;
return shell;
}
protected override IModuleCatalog CreateModuleCatalog()
{
ModuleCatalog modules = new ModuleCatalog();
modules.AddModule(typeof(FirstHello.Module));
modules.AddModule(typeof(SecondHello.Module1));
return modules;
}
}

The xaml Shell which would display both our Modules will look as follows:

<UserControl xmlns:toolkit="http://schemas.microsoft.com/winfx/2006/xaml/presentation/toolkit" x:Class="SLPrismPart1.Shell"
 xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
 xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
 xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
 xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
 xmlns:Regions="clr-namespace:Microsoft.Practices.Prism.Regions;assembly=Microsoft.Practices.Prism"
 mc:Ignorable="d"
 d:DesignHeight="300" d:DesignWidth="400">
<Grid x:Name="LayoutRoot" ShowGridLines="True">
<Grid.ColumnDefinitions>
 <ColumnDefinition/>
 <ColumnDefinition/>
 </Grid.ColumnDefinitions>
 <Grid.RowDefinitions >
 <RowDefinition Height="Auto"/>
 <RowDefinition Height="*"/>
 </Grid.RowDefinitions>
<TextBlock Text="Sample MVVM Hello World Application" FontSize="16" HorizontalAlignment="Center" Grid.Row="0" Grid.ColumnSpan="2"/>

<ContentControl Grid.Row="1" Grid.Column="0" x:Name="FirstHello" Regions:RegionManager.RegionName="FirstHello" HorizontalAlignment="Center"
VerticalAlignment="Center"/>
 <ContentControl Grid.Row="1" Grid.Column="1" x:Name="SecondHello" Regions:RegionManager.RegionName="SecondHello" HorizontalAlignment="Center"
 VerticalAlignment="Center"/>
</Grid>
</UserControl>

The Application_Startup in the App.xaml will look as follows :

 private void Application_Startup(object sender, StartupEventArgs e)
{
Bootstrapper bootStrapper = new Bootstrapper();
bootStrapper.Run();
}

We are done lets give it a run:

Silverlight Prism Series output

In my next post I would go more indepth into the Prism Framework. Thanks. Happy coding.