XamarinTutorial

Introduction to Cross-Platform

One of the advantages to using Cross-Platform over the traditional platform-specific approach is the level of code-sharing you can achieve across iOS, Android and Windows. In this tutorial, we will explore two ways to structure your shared code - Portable Class Libraries (PCLs) and Shared Projects.

Using Shared Projects

Shared Projects, sometimes referred to as "Shared Application Projects" allow you to define a specific project type where the intent is to actually share all of the files in that project with other projects. It acts just like File Linking – except you only have to add one reference to your target to get all of the files added. The IDE then treats all the files and assets included in the shared project as if they were part of each of your platform projects. In addition, because the IDE knows about the relationships, all the normal refactoring and navigation tools should work just fine. The key thing to know about Shared Projects is that they simply define a project container. Unlike all the other project types you typically work with, Shared Projects do not have any output – no EXE or DLL is produced by compiling a shared project. In fact, by itself, the Shared Project isn't even compiled. It must be added to another project in order to have the compiler process the files. When you add a reference to a shared project, the compiler and build tools will act as if all the files in that shared project were added directly to the target. In other words, the C# source files in the shared project are compiled directly with the target, using that project's build settings.

• The build action you select in the shared project becomes the build action used for each target project.
• Shared Projects are the preferred way to manage source-level sharing.
• The only reason to not use them is if you are required to use an older version of the build tools.
• In order to add references to Shared Projects in Visual Studio 2013, you need an extension.

Using Portable Class Libraries

Portable Class Libraries(PCLs) attempt to address this problem by creating a library that is capable of running on multiple .NET platforms (Xamarin.iOS, Xamarin.Android, Windows, etc.). They provide a more structured container for sharing code which is not tied to a specific runtime but also require more architecture and thought when using platform-specific features. Let's take a closer look at how these work.

When you run into a situation where you need to use a platform-specific feature from your shared code, you will need to create an abstraction over the feature. Before you go through that effort however, you should look to see if an abstraction already exists. Here are some good places to look:

• Xamarin.Social The Xamarin.Social component provides an abstraction for popular social networking frameworks such as Facebook and Twitter.
• Xamarin.Auth Xamarin.Auth provides a cross-platform implementation for client-side OAuth interactions.
• Xamarin.Mobile Xamarin.Mobile provides an abstraction for common mobile services such as the camera.
• Open source plugins A big list of community-created cross-platform plug-ins.
• .NET Foundation The .NET Foundation has a bunch of open-source code.
• NuGet NuGet is the place to find shared binary components
• Xamarin Component Store The Xamarin component store has some commercial binary components.

Introduction to Xamarin

• What is Xamarin.Forms?
• Installing Xamarin
• Pages, Controls and Layout
• Using platform-specific features

Introduction to Xamarin.Forms

There are two common approaches to using Xamarin to build mobile applications:

1. The traditional approach where we share primarily business logic and data structures.
2. The Xamarin.Forms approach where we also share the business logic and data structures, but also define the UI using a common set of platform-independent controls - allowing us to also share the UI design. Let's explore this in a bit more detail together.

In Xamarin.forms, remember that each of our applications is made from two components:

Shared code(Portable Class Library) which holds our logic and UI definition and the Platform-Specific projects which are the actual applications we will deploy to the devices and app stores. The PCL is great because it's shared, but it has significant limitations in terms of the APIs we can use.

Many of the platform features which make iOS, Android, and Windows unique are unavailable to us. Those features are available in the platform-specific projects, but then we have to write the code in a non-shared way and try to find some way to "plug" it into our shared UI.

Resources and Styles in Xamarin.Forms

In these video, we will explore how to use static resiurce in XAML

• Avoid duplicate XAML with Resources
• Create consistent UI with Styles
• Make your Resources and Styles available across your entire app
• Apply the user's accessibility choices with built-in Styles

SQLite and Mobile Data

In this videos, we will explore how to use SQLite and the SQLite.NET ORM to manage local data in your Xamarin.iOS, Xamarin.Android and Windows applications

• Data storage options
• Working with SQLite
• Working with SQLite asynchronously

In mobile development there are several options when it comes to persisting data within our mobile applications. Depeninding on the different environment the storage type are changed

1. Preference(Android-SharedPreferences, iOS-NSUserDefaults, Windows-IsolatedStorageSettings/ApplicationDataContainer)
2. File System
3. Database

Consuming REST-based Web Services

In these video, we will explore REST-Based web request, making HTTP request and handeling data

• Obtain the device's network capabilities
• Introduction to REST
• Consuming REST services with Xamarin
• Integrating with the platform

In this repository added some projects which are

1. XAMLCalculator This is the exercise of Resources and Styles in Xamarin.Forms tutorial of the Xamarin University
2. DataStorageDemo This project is the exercise of SQLite and Mobile Data tutorial of the Xamarin University. To compile this you need add a Nuget Package SQLite-net-pcl