Presentation about MVVM pattern in mobile cross platform development. It shows how to use MVVM pattern in MvvmCross and Xamarin.Forms

1. MVVM pattern as a way of creating
loosely coupled, maintainable and
testable Xamarin apps
Sylwester Wieczorkowski
sylwester.wieczorkowski@leaware.com

2. Xamarin Platform
ü Native UI, native API access,
and native performance
ü Anything you can do in
Objective-C, Swift, or Java you
can do in C# with Xamarin
ü Ship cutting-edge apps with
same-day support for new OS
releases

3. Xamarin Test Cloud
ü Tests behave as users do–
performing taps, pinches,
swipes, and more
ü Integrates with CI for
continuous automated testing,
testing apps on every change
ü Ensures apps look and feel
excellent with full-frame
screenshots and video playback

4. Xamarin Insights + HockeyApp
ü Get meaningful crash reports
with the most reliable crash
reporting on the market
ü See how your app is used and
what your testers have already
covered
ü Communicate with your users
and get feedback, support
requests, and bug reports from
within your app

5. Silo Approach
iOS App
Objective-C
XCode
Android App
Java
Android Studio
Windows App
C#
Visual Studio

6. Traditional Xamarin Approach
iOS C# UI Android C# UI Windows C# UI
Shared C# Logic

7. Traditional Xamarin Approach
ü Apps that require specialized interactions
ü Apps with highly polished design
ü Apps that use many platform-specific APIs
ü Apps where custom UI is more important than code sharing

8. What’s MVVM?
View ViewModel Model
Presentation and Presentation Logic Business Logic and Data
Data Binding

9. Traditional Xamarin Approach
v Create your own framework
• Shared Project
• Portable Class Library
v Use an existing MVVM solution
• Bind
• MVVM Light
• ReactiveUI
• MvvmCross
Project Styles

10. DEMOMvvmCross

11. Belfius Direct Mobile

12. Belfius Direct Mobile

13. BNP Paribas Fortis

14. BNP Paribas Fortis

15. Xamarin.Forms Approach
Shared C# Logic
Xamarin.Forms - Shared C# UI

16. Xamarin.Forms Approach
ü Data entry apps
ü Prototypes and proofs-of-concept
ü Apps that require little platform-specific functionality
ü Apps where code sharing is more important than custom UI

17. Xamarin.Forms Approach
v Create your own framework
• Stick to Xamarin.Forms mechanisms
(e.g. DependencyService,
MessagingCenter)
• Implement INotifyPropertyChanged
and ICommand
Project Styles
v Use an existing MVVM solution
• Mugen MVVM Toolkit
• MVVM Light
• FreshMvvm
• MvvmCross-Forms
• Prism

18. Prism for Xamarin.Forms
ü MVVM Support
ü Commanding
ü Messaging
ü Navigation
ü Page Dialog Service
ü Logging
ü Dependency Injection

19. DEMOPrism for Xamarin.Forms