Overview

This topic describes how to build a XAML-based module catalog for a solution that uses the Composite Application Library. The module catalog contains the metadata for modules and modules groups in the application; it can be populated in different ways and from different sources. For example, it can be populated from a XAML file. An advantage of having a XAML catalog is that declaring object elements in XAML instantiates the corresponding .NET Framework object through its default constructor.

Note:
This topic assumes that you are familiar with modules. For more information about modules, see the Module technical concept.

Prerequisites

This topic assumes that you have a solution built with the Composite Application Library that has a module. For information about how to do this, see the following topics:

• How to: Create a Solution Using the Composite Application Library. This topic describes how to create a solution with the Composite Application Library.
• How to: Create a Module. This topic describes how to add a new module to your solution.

Steps

The following procedure describes how to build a XAML-based module catalog.

To build a XAML-based module catalog

1. Add a new .xaml file, named ModulesCatalog.xaml, in your Shell project.
2. The root element of this .xaml file should be a ModuleCatalog instance. In addition to specifying the default namespaces, this root element must also specify the Modularity namespace, as shown in the following code.
   XAML

   Copy

   xmlns:Modularity="clr-namespace:Microsoft.Practices.Composite.Modularity;assembly=Microsoft.Practices.Composite"
   

3. Add a ModuleInfoGroup child element to the ModuleCatalog root element for each module group you have.

   Note:
   Putting modules inside module groups is optional. The properties that are set for a group will be applied to all its contained modules. Note that modules can also be registered without being inside a group.

4. Set the corresponding properties to each ModuleInfoGroup. The properties defined by the ModuleInfoGroup class are the following:
   • Ref. The content of this property indicates the location from where the modules in the module group should be obtained.
   • InitializationMode. This property specifies how all the group modules are going to be initialized. The possible values for this property are: WhenAvailable and OnDemand.
5. Add ModuleInfo objects to the catalog. ModuleInfo objects can be registered within a group or without a group. Note the following:
   • If you want to register modules in a group, put one ModuleInfo element inside the ModuleInfoGroup tags for each module that the module group contains.
   • If you want to register modules without a group, put the ModuleInfo element inside the ModuleCatalog tags.

   Each ModuleInfo instance has the following properties:

   • ModuleName. This property specifies the logical name of the module.
   • ModuleType. This property specifies the type of the module.
   • Ref. The content of this property indicates the location from where the modules in the module group should be obtained. This property should be set if the module is not inside a module group.
   • InitializationMode. This property specifies how all the group modules are going to be initialized. The possible values for this property are WhenAvailable and OnDemand. The default value is WhenAvailable.
   • DependsOn. This property can be set to a list of the modules names that this module depends on.

     Note:
     For more information about setting dependencies between modules, see How to Define Dependencies between Modules.

Note:

The module catalog can also be created programmatically, by looking up modules in a specific folder or by reading a configuration file. For more information about populating a module catalog programmatically, see How to: Populate the Module Catalog from Code. For more information about populating a module catalog from a directory lookup or from a configuration file in WPF applications, see How to: Populate the Module Catalog from a Configuration File or a Directory in WPF.

The following code shows the XAML-based Module Catalog implementation included in the Remote Modularity QuickStart.

<Modularity:ModuleCatalog xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
               xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
                xmlns:sys="clr-namespace:System;assembly=mscorlib"
               xmlns:Modularity="clr-namespace:Microsoft.Practices.Composite.Modularity;assembly=Microsoft.Practices.Composite">
    <Modularity:ModuleInfoGroup Ref="ModuleX.Silverlight.xap" InitializationMode="OnDemand">
        <Modularity:ModuleInfo ModuleName="ModuleX" ModuleType="ModuleX.ModuleX, ModuleX.Silverlight, Version=1.0.0.0" />
    </Modularity:ModuleInfoGroup>
    <Modularity:ModuleInfoGroup Ref="ModulesWY.Silverlight.xap" InitializationMode="WhenAvailable">
        <Modularity:ModuleInfo ModuleName="ModuleY" ModuleType="ModuleY.ModuleY, ModulesWY.Silverlight, Version=1.0.0.0">
            <Modularity:ModuleInfo.DependsOn>
                <sys:String>ModuleW</sys:String>
            </Modularity:ModuleInfo.DependsOn>
        </Modularity:ModuleInfo>
        <Modularity:ModuleInfo ModuleName="ModuleW" ModuleType="ModuleW.ModuleW, ModulesWY.Silverlight, Version=1.0.0.0">
        </Modularity:ModuleInfo>
    </Modularity:ModuleInfoGroup>
    <!-- Module info without a group -->
    <Modularity:ModuleInfo Ref="ModuleZ.Silverlight.xap" ModuleName="ModuleZ" ModuleType="ModuleZ.ModuleZ, ModuleZ.Silverlight, Version=1.0.0.0" />
</Modularity:ModuleCatalog>

Outcome

A module catalog, which contains metadata for all the application's modules, is created and populated from a XAML file.

More Information

For information about other ways that you can populate the module catalog, see the following topics:

• How to: Populate the Module Catalog from Code
• How to: Populate the Module Catalog from a Configuration File or a Directory in WPF

For more information related to working with modules, see the following topics:

• How to: Load Modules On Demand
• How to: Define Dependencies Between Modules
• How to: Prepare a Module for Remote Downloading

For a complete list of How-to topics included with the Composite Application Guidance, see Development Activities.

Home page on MSDN | Community site