Book Image

Xamarin 4.x Cross-Platform Application Development - Third Edition

By : Peppers
Book Image

Xamarin 4.x Cross-Platform Application Development - Third Edition

By: Peppers

Overview of this book

Xamarin is a leading cross-platform application development tool used by top companies such as Coca-Cola, Honeywell, and Alaska Airlines to build apps. Version 4 features significant updates to the platform including the release of Xamarin.Forms 2.0 and improvements have been made to the iOS and Android designers. Xamarin was acquired by Microsoft so it is now a part of the Visual Studio family. This book will show you how to build applications for iOS, Android, and Windows. You will be walked through the process of creating an application that comes complete with a back-end web service and native features such as GPS location, camera, push notifications, and other core features. Additionally, you’ll learn how to use external libraries with Xamarin and Xamarin.Forms to create user interfaces. This book also provides instructions for Visual Studio and Windows. This edition has been updated with new screenshots and detailed steps to provide you with a holistic overview of the new features in Xamarin 4.
Table of Contents (13 chapters)

Accessing the photo library and camera


The last major feature of Xamarin.Mobile is the ability to access photos in order to give users the ability to add their own content to your applications. Using a class called MediaPicker, you can pull photos from the device's camera or photo library and optionally display your own UI for the operation.

Let's modify MessageViewModel to support photos. First, add the following property:

public string Image { get; set; } 

Next, we need to modify the following lines in the SendMessage method:

if (string.IsNullOrEmpty(Text) && string.IsNullOrEmpty(Image))
   throw new Exception("Message is blank.");
 
//Then further down 
var message = await service.SendMessage(new Message
{
     UserName = settings.User.Name,
     Conversation = Conversation.Id,
     Text = Text,
     Image = Image,
     Location = location,
});
//Clear our variables 
Text =
      Image = null;  

Next...