Xamarin Webinar on Say Hello to Xamarin.Forms

1. Say Hello To Xamarin.Forms
Nish Anil
@nishanil | nish@xamarin.com

2. Traditional Xamarin Development
Using the Native UI SDKs
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Build native UIs
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UIKit & Storyboards on iOS
■
AXML for Android
■
XAML for Windows Phone
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Write shared C# code
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Database, Web Services
■
Business Logic
■
Share 60-80% of the code
UIKit Layout XAML

3. Using Xamarin.Forms
Shared UI Code!
To Build the User Interface
■
Use the same strategies for sharing
■
Database, Web Services
■
Business Logic
■
Build the UI with a single shared
codebase
■
Share 99% of the code
UIKit Layout XAML

4. Using Xamarin.Forms
Shared UI Code!
■
Code sharing/re-use
■
Native look and feel
■
Access to native SDKs using Custom
Renderers and DependencyService
■
Camera, accelerometer, GPS,
■
NFC & more on Android
■
PassKit & more on iOS
■
Tiles & more on Windows Phone
Benefits UIKit Layout XAML
Shared C# User Interface Code

5. Meet Xamarin.Forms
Build native UIs for iOS, Android and Windows Phone
from a single, shared C# codebase.

6. Meet Xamarin.Forms
Build native UIs for iOS, Android and Windows Phone
from a single, shared C# codebase.

7. Meet Xamarin.Forms
Build native UIs for iOS, Android and Windows Phone
from a single, shared C# codebase.

8. Meet Xamarin.Forms
Build native UIs for iOS, Android and Windows Phone
from a single, shared C# codebase.

9. Meet Xamarin.Forms
Build native UIs for iOS, Android and Windows Phone
from a single, shared C# codebase.

10. Meet Xamarin.Forms
Build native UIs for iOS, Android and Windows Phone
from a single, shared C# codebase.

11. Meet Xamarin.Forms
public class HelloWorld : ContentPage
{
public HelloWorld ()
{
var button = new Button
{ Text = "Say Hello" } ;
button.Clicked += SayHelloClicked;
Content = new StackLayout {
new Label { Text = "Hello World" } ,
button
};
}
void SayHelloClicked (object s, EventArgs e)
{
// do something
}
}
<?xml version="1.0" encoding="UTF-8"?>
<ContentPage xmlns="http://xamarin.com/schemas/2014/fo
x:Class="HelloForms.HelloWorld">
<StackLayout>
<Label Text="Hello World" />
<Button Text="Say Hello"
OnClick="SayHelloClicked" />
</StackLayout>
</ContentPage>
public partial class HelloWorld : ContentPage
{
public HelloWorld ()
{
InitializeComponent ();
}
void SayHelloClicked (object s, EventArgs e)
{
// do something
}
}
C# XAML

12. Demo
■
File > New Project
■
Create a screen
■
Add some code
■
Run on iOS, Android,
& Windows Phone

14. How Xamarin.Forms works
Anatomy of a Xamarin.Forms Solution
■
PCL or Shared Project

15. How Xamarin.Forms works
Anatomy of a Xamarin.Forms Solution
■
PCL or Shared Project
■
NuGet Package

16. How Xamarin.Forms works
Anatomy of a Xamarin.Forms Solution
■
PCL or Shared Project
■
NuGet Package
■
App Class

17. How Xamarin.Forms works
Anatomy of a Xamarin.Forms Solution
■
PCL or Shared Project
■
NuGet Package
■
App Class
■
Android app

18. How Xamarin.Forms works
Anatomy of a Xamarin.Forms Solution
■
PCL or Shared Project
■
NuGet Package
■
App Class
■
Android app
■
iOS app

19. How Xamarin.Forms works
Anatomy of a Xamarin.Forms Solution
■
PCL or Shared Project
■
NuGet Package
■
App Class
■
Android app
■
iOS app
■
Windows Phone app

20. Platform Renderers
Taking Xamarin.Forms UI to the people (devices)
?
?
?

21. Platform Renderers
Taking Xamarin.Forms UI to the people

22. Platform Renderers
Taking Xamarin.Forms UI to the people

23. Platform Renderers
Taking Xamarin.Forms UI to the people

24. Xamarin.Forms brings common UX to everyone
iOS does not have a native control
for the iPhone, however
Xamarin.Forms uses
UISplitViewController on iPad.
Android has a native 'drawer'
control which Xamarin.Forms uses.
Windows Phone doesn’t have a
comparable UI metaphor, so
Xamarin.Forms provides an
implementation.
MasterDetailPage

25. Xamarin.Forms brings common UX to everyone
iOS has the UINavigationController
which Xamarin.Forms leverages.
Android has the navigation stack
built in, but Xamarin.Forms adds
the automatic 'back' button for API
consistency.
Windows Phone also has a back-
stack with hardware button, so
Xamarin.Forms takes advantage of
that.
NavigationPage

26. 140+ new Controls!
http://components.xamarin.com
From our Partners!

27. Demo
■
Write Platform Specific Code

28. Dependency Service
Easily call into platform-specific code
■
In the common code
■
Code to an Interface
public interface ITextToSpeech
{
void Speak (string text);
}

29. Dependency Service
Easily call into platform-specific code
■
In the common code
■
Code to an Interface
■
Use DependencyService
public interface ITextToSpeech
{
void Speak (string text);
}
DependencyService.Get<ITextToSpeech>().Speak("Hello from Xamarin Forms");

30. Dependency Service
Easily call into platform-specific code
■
In the common code
■
Code to an Interface
■
Use DependencyService
■
For each platform
■
implement the Interface
[assembly: Xamarin.Forms.Dependency (typeof (Speech))]
public class Speech : ITextToSpeech
{
public Speech () { }
public void Speak (string text)
{
var speechSynthesizer = new AVSpeechSynthesizer ();
var speechUtterance = new AVSpeechUtterance (text) {
Rate = AVSpeechUtterance.MaximumSpeechRate/4,
Voice = AVSpeechSynthesisVoice.FromLanguage ("en-US"),
Volume = 0.5f,
PitchMultiplier = 1.0f
} ;
speechSynthesizer.SpeakUtterance (speechUtterance);
}
}

31. Dependency Service
Easily call into platform-specific code
■
In the common code
■
Code to an Interface
■
Use DependencyService
■
For each platform
■
implement the Interface
■
use Dependency
attribute on the
assembly
[assembly: Xamarin.Forms.Dependency (typeof (Speech))]
public class Speech : ITextToSpeech
{
public Speech () { }
public void Speak (string text)
{
var speechSynthesizer = new AVSpeechSynthesizer ();
var speechUtterance = new AVSpeechUtterance (text) {
Rate = AVSpeechUtterance.MaximumSpeechRate/4,
Voice = AVSpeechSynthesisVoice.FromLanguage ("en-US"),
Volume = 0.5f,
PitchMultiplier = 1.0f
} ;
speechSynthesizer.SpeakUtterance (speechUtterance);
}
}

32. Data Binding
Sync views and models
■
Enables MVVM-style development
■
SetBinding in C#
■
{Binding} in XAML
■
also supports the Command pattern

33. Custom Renderers
Extend or Create Xamarin.Forms Controls
■
Subclass the built-in Platform Renderers
■
Build your own Xamarin.Forms
control and renderers
(eg. OxyPlot)

34. Further Reading…
■
developer.xamarin.com
■
forums.xamarin.com
■
Creating Mobile Apps with
Xamarin.Forms - Charles Petzold
Available as a FREE download

35. Thanks!
Nish Anil
@nishanil | nish@xamarin.com