Book Image

Mastering Xamarin UI Development - Second Edition

By : Steven F. Daniel
Book Image

Mastering Xamarin UI Development - Second Edition

By: Steven F. Daniel

Overview of this book

This book will provide you with the knowledge and practical skills that are required to develop real-world Xamarin and Xamarin.Forms applications. You’ll learn how to create native Android app that will interact with the device camera and photo gallery, and then create a native iOS sliding tiles game. You will learn how to implement complex UI layouts and create customizable control elements based on the platform, using XAML and C# 7 code to interact with control elements within your XAML ContentPages. You’ll learn how to add location-based features by to your apps by creating a LocationService class and using the Xam.Plugin.Geolocator cross-platform library, that will be used to obtain the current device location. Next, you’ll learn how to work with and implement animations and visual effects within your UI using the PlatformEffects API, using C# code. At the end of this book, you’ll learn how to integrate Microsoft Azure App Services and use the Twitter APIs within your app. You will work with the Razor Templating Engine to build a book library HTML5 solution that will use a SQLite.net library to store, update, retrieve, and delete information within a local SQLite database. Finally, you will learn how to write unit tests using the NUnit and UITest frameworks.
Table of Contents (15 chapters)

Creating the WalkEntryPageViewModel using C#

Now that we have updated the WalksMainPage code-behind file so that it communicates with our WalksMainPageViewModel as well as each of the associated data bindings for the ContentPage that will be used by the ViewModel, the next step is to create and implement the underlying C# code for our ViewModel that will be used by our WalkEntryPage code-behind file. This allows the user to add or edit walk trail information within our WalkDataModel data model, as well as validate the information that's provided.

Let's take a look at how we can achieve this by following these steps:

  1. First, create a new Empty Class called WalkEntryPageViewModel, like you did in the section entitled Creating the WalksMainPageViewModel using C#, located within this chapter.
  1. Next, ensure that the WalkEntryPageViewModel.cs file is displayed within the...