Book Image

Mastering Xamarin.Forms

By : Ed Snider
Book Image

Mastering Xamarin.Forms

By: Ed Snider

Overview of this book

Discover how to extend and build upon the components of the Xamarin.Forms toolkit to develop an effective, robust mobile app architecture. Starting with an app built with the basics of the Xamarin.Forms toolkit, we’ll go step by step through several advanced topics to create a solution architecture rich with the benefits of good design patterns and best practices. We’ll start by introducing a core separation between the app’s user interface and the app’s business logic by applying the MVVM pattern and data binding. Discover how to extend and build upon the components of the Xamarin.Forms toolkit to develop an effective, robust mobile app architecture. Starting with an app built with the basics of the Xamarin.Forms toolkit, we’ll go step by step through several advanced topics to create a solution architecture rich with the benefits of good design patterns and best practices. We’ll start by introducing a core separation between the app’s user interface and the app’s business logic by applying the MVVM pattern and data binding. Then we will focus on building out a layer of plugin-like services that handle platform-specific utilities such as navigation, geo-location, and the camera, as well as how to use these services with inversion of control and dependency injection. Next we’ll connect the app to a live web-based API and set up offline synchronization. Then, we’ll dive into testing the app—both the app logic through unit tests and the user interface using Xamarin’s UITest framework. Finally, we’ll integrate Xamarin Insights for monitoring usage and bugs to gain a proactive edge on app quality.
Table of Contents (17 chapters)

Automated UI testing


While unit tests ensure that a significant amount of code is tested, it is specifically focused on testing the logic within the app, leaving the user interface largely untested. This is where UI testing comes into play. UI testing allows us to automate specific actions within the app's user interface to assert that they function properly—just like regular unit tests assert that business logic delivers the desired results or functionality.

Xamarin provides a very rich set of tools for performing automated UI tests—both locally and in the Xamarin Test Cloud. UI tests can be written in C# and NUnit using Xamarin's UITest framework or in Ruby using Xamarin's Calabash framework. For the purposes of this book, we will only focus on using the C# approach using Xamarin.UITest.

The Xamarin UITest framework

The UITest framework enables you to automate interactions with an app using C# and the NUnit testing suite. All interactions take place through an instance of IApp. The ConfigureApp...