MVVM Basics with Caliburn.Micro

Presented by Stefan Nuxoll, Lithium PC

Overview

• What is MVVM (And why do I care?)• Getting Started (What is Caliburn.Micro?)• Slides are Pointless (Let’s write some code!)• Hello, World is Boring (Let’s do something real)• Review / Q&A

Assumptions

• This is an intermediate (200) level presentation• Working knowledge of C# and .Net needed• You do NOT need to know what IoC or Convention-over-

configuration mean• You do NOT need to know XAML• Though it will help

What is MVVM?And why do you care?

MVVM Explained

• Model-View-ViewModel• Data is pulled by UI, not pushed to it• Complete separation between interface and code

MVVM Relationships

ViewModel

View Model

Benefits of MVVM

• Testable!• UI/UX developers can focus on their job• Cleaner, more maintainable code

Getting StartedWhat is Caliburn.Micro?

What is Caliburn.Micro?

• Fully featured MVVM framework• Utilizes IoC and convention-over-configuration• Fully customizable and extremely flexible• Under 3K LoC (lean and easy to modify)• Supports WPF, Silverlight, Windows Phone and Windows RT• Available at http://caliburnmicro.codeplex.com

Why use Caliburn.Micro?

• Don’t reinvent the wheel• Conventions and Actions• Built-in support for IoC (typically the MEF)• Already has support for all major .net environments

Slides are PointlessLet’s write some code!

Before We Begin

• Sample code and presentation are available online• We will be starting from scratch• If you’ve got Visual Studio on your laptop, feel free to follow along

Creating the Project

• Create a new WPF application• Install Caliburn.Micro from NuGet• Configure bootstrapper

Demonstration

Wiring It Up

• Create our first View• Create our first ViewModel• Demonstrate Data Binding and Actions

Demonstration

Hello, World is BoringLet’s do something real

Let’s Talk to Netflix

• Anyone know what Odata is?• Odata is a great idea with a so-so implementation• Somebody saw SOAP and WSDL and said “What the fuck is

this?”• Think of it as SOAP-but-better (not exactly high praise)• .Net 3.5 and higher have native support, integrates with LINQ• Netflix has an Odata endpoint, making our lives easier

Okay, Let’s *ACTUALLY* Talk to Netflix

• Done complaining about Odata• Add service reference in visual studio• Create a helper class to handle querying Netflix• .Net’s Odata support works with LINQ (easy peasy!)

Demonstration

User Interface

• Search box• Results list• Let’s show cover art too

Demonstration

Holy CrapI understood all that (I think)

MVVM Review

• Cleaner, more readable code• Modular, testable• Separation of UI from code• Means UI/UX developers don’t need to know jack about programming

• Pull, not push• Stop creating a ton of controls in code-behind, let the UI handle all that

Q&A

• You don’t actually have questions, do you?• Fine, I guess I’ll answer them.