The document discusses tips for developing code that can target multiple platforms. It recommends understanding your audience and goals to determine which platforms to target. The document suggests isolating common code like business logic and data layers into portable class libraries to be shared across platforms. Platform-specific code like user interfaces would be separate. It provides an overview of portable class libraries in .NET and design patterns like MVVM for writing cross-platform code.

1. Tips & Tricks for Targeting Multiple Platforms with Portable Code
Presented by Sarah Dutkiewicz, Cleveland Tech Consulting
sarah@cletechconsulting.com

3.  Scenarios
 Tips & tricks for general multiple platform development
 Overview of Portable Class Library in .NET

4.  Experiences that cross from one device/platform to another
 Microsoft Account
 Office
 SkyDrive
 Xbox SmartGlass

5.  Formerly known as a Windows Live ID
 Combination of email address and password
 Unified login for Microsoft tools and other apps that ask for a Microsoft account
 Xbox LIVE
 Outlook.com
 SkyDrive
 Windows Phone
 Skype

7.  Data storage in the cloud
 Office in the browser – including Word,
Excel, PowerPoint, and OneNote
 Supported platforms include:
 Windows 8 (built-in)
 Windows Vista and later
 Mac OS X
 Mobile
 Windows Phone
 iPhone / iPad
 Android

8.  Found for Mac
 iAnnotate for iPad and Android
 SoundGecko for iPhone, Android, and Windows Phone
 Genius Scan+ for iPhone, iPad
 Remarks for iPad
 DocScan for iPhone and iPad

10. How to Develop For Multiple Devices/Platforms

11.  The better understanding of your audience,
the better understanding of which platforms
to target.
 The better understanding of which platforms
to target, the better view of what features are
available as an overall view and platform-
specific

13.  Be sure you understand what it is
you are building and what
platform(s) you are targeting.
 Write the code once and reuse it,
rather than writing the code in
multiple places and then realizing it
can be isolated into one library.

15.  Media – images, video
 Design aspects
 Models
 View Models
 Consumed APIs/RESTful services

16.  Web & Windows Phone – Perhaps HTML5, Silverlight, or C#
 Web,Windows Phone, and Windows Store – C#
 Web & general mobile – consider HTML5

18.  User Interface
 Business Logic
 Data Layer

19.  Some code is shareable without the portable class library
 Share the code that would be the same on each platform
 Typically not the UI
 Mostly as much business logic as possible
 Perhaps data layer
 Portable view models
 Validation
 Use design patterns that lend themselves to reusability
 Model-View-ViewModel (MVVM)
 Model-View-Controller (MVC)
 Use third party tools that support cross-platform development

20.  Appcelerator
 PhoneGap
 RhoMobile
 WidgetPad
 MoSync

21.  Visual Studio for targeting Windows
 MonoGame to help target many platforms:
 iOS
 Android
 Mac OS X
 Linux
 Windows 8 Metro
 Futures include:
 Windows Phone 8
 OUYA (Android-based gaming station)
 PlayStation Mobile

22. A look at Portable Class Libraries

23.  Desktop
 Web
 Phone
 Cloud
 Xbox
 Tablets

24.  .NET 4 and Silverlight 4
 Portable Library Tools for Visual Studio
2010
 Built-in Portable Library support in Visual
Studio 2012

25.  .NET Framework 4, Update 4.0.3 for the
.NET Framework 4, and .NET Framework
4.5
 .NET for Windows store apps
 Windows Phone 7 and higher (Windows
Phone SDK 8.0 for Windows Phone 8
support)
 Silverlight 4 and 5
 Xbox 360

27.  They must be shared across the target platforms you
selected.
 They must behave similarly across those platforms.
 They must not be candidates for deprecation.
 They must make sense in a portable environment,
especially when supporting members are not
portable.
 Portable Class Library support appears under
Version Information for a MSDN article

28.  Include shared business logic and data layer logic in the portable class libraries
 Use MVVM to write the apps
 Models and View Models can be shared across platforms and included in portable
libraries
 Platform-specific views
 Portable abstractions for non-portable functionality
 Implement the abstractions for each platform
 Use IoC or service locator to hook up implementations

29. • How to display information
• Written in XAML, HTML, some other markup language
• Platform-specific
View
• What information to display
• Flow of interaction
• Can be shared in a portable class library
View Model
• Data objects
• Business logic
• Can be shared in a portable class library
Model

30. Portable
Class Library
(Models &
View Models)
Windows
Store App
(Views)
Windows
Phone App
(Views)
Silverlight
(Views)

32.  Calling Non-Portable Members from a Portable Class
 Cannot call the non-portables directly
 Need to create an abstract class in the Portable Class Library project and use that class
from all portable code

33.  HelpDesk Application
 Metro Style App
 Windows Phone 7 App
 Download Source Code

34.  Store common logic in the portable class library
 Business logic, but not UI
 Use abstract classes to work with non-portable code
 For example, this may be applied to the data layer.
 Use the MVVM pattern to help minimize code.

35.  MVVM
 MVVM Light Toolkit (portable fork)
 MvvmCross
 IoC
 Autofac
 PortableIoC
 Ninject (portable fork)
 Microsoft.Composition
 Others
 Json.NET
 Metrolog
 Zlib.Portable
 Portable PRISM

36.  Write Portable Code
 Visual Studio Toolbox: Portable Class Libraries
 Portable Class Libraries Contrib
 Build 2012: Create Cross-platform Apps using Portable Class Libraries
 .NET 4.5: David Kean and Mircea Trofin – Portable Libraries
 Coding4Fun: Portable is as portable does… Maximizing code reuse via the magic of the
Portable Class Library
 Coding4Fun: Digging into your code with the free Microsoft Code Digger and the
power of Pex
 CodeProject: MonoGame Goes Portable
 How to Make Portable Class Libraries Work forYou
 Example: Disentanglement by Daniel Plaisted

38.  Portable Class Libraries and other portable libraries make it easy to develop for
multiple platforms.
 Know the lay of the land.
 Know your audience.
 Know your goals for your app.
 Keep your commonalities together.
 Develop accordingly.