Now that you’re all oriented and able to communicate in close quarters I want to see some rockin’ apps! Thanks again for attending! And for those that didn’t make it, you missed an AWESOME magic trick! My best yet.

Session Resources

• Link to Presentation and Class Code Examples
• Link to Session Recording

Overview of Sessions

The links below lead you to Meetup Events where you can RSVP. We look forward to seeing you at our next session!

1. Introductory Lecture (Nov 27th by Danny & Kevin)
2. Introduction to XAML and WinRT’s powerful Control Framework; (Dec 4th by Danny & Kevin Click here for the video recording)
3. Page-Navigation Model and Application Lifecycle (Jan 8th by Danny Click here for the video recording)
4. Fundamentals (Async/Await, WinRT API, Security) (Jan 15th by Kevin Click here for the video recording)
5. Settings and Search Contract (Jan 28th by Danny Click here for the video recording)
6. Share Contract (Feb 4th by Kevin Click here for the video recording)
7. Live Tiles and Background Tasks (March 18th by Kevin Click here for the video recording)
8. Orientation Handling and Proximity using Near Field Communication (NFC) (March 25th by Danny Click here for the video recording)
9. Introduction to ModelViewViewModel (MVVM) (April 8th by Danny)
10. InterKnowlogy’s WinRT MVVM Framework Session Part I/II(April 22nd by Kevin)
11. InterKnowlogy’s WinRT MVVM Framework Session Part II/II(May 6th by Danny)
12. Presentation of Hackathon Results + Certificate/Prize Giveaway(May 20th by Danny and Kevin)

With the advent of Microsoft’s latest OS, a lot of people are asking how to get setup for developing Windows 8 applications. Here is a short post about getting a development environment for Windows 8 up and running.

Where to find Windows 8?

Full OEM

A full copy of Windows 8 can be purchased at http://www.newegg.com/Product/Product.aspx?Item=N82E16832416552. Be careful to only purchase the Windows 8 Pro version and not the Windows 8 version. Only Windows 8 Pro supports developing.

Upgrade

This is the preferred option.  Windows 8 is great OS. This option also guarantees the developer the best environment for developing for Windows 8. Anyone machine running Windows XP SP3, Vista, or Windows 7 can be upgraded. The upgrade cost is currently $40 (until Jan. 31st 2013) at http://windows.microsoft.com/en-US/windows/buy?ocid=GA8_O_WOL_DIS_ShopHP_FPP_Light for digital media. Developers can/need to create physical media from the digital media by using the Windows 7 USB/DVD download tool in order to create a bootable USB or DVD available at http://www.microsoftstore.com/store/msstore/html/pbPage.Help_Win7_usbdvd_dwnTool. The tool allows users to create a bootable DVD or USB. Typically the USB has been found to be the easiest. Physical upgrade media is also available at the same site for $70 (until Jan 31st 2013).

Evaluation Copy of Windows 8

The evaluation copy can be installed natively, in a virtual machine, or on a bootable VHD. The evaluation copy cannot be upgraded and is only good for 90 days. After 90 days Windows would need to be installed via a clean install. The evaluation copy can be found here http://msdn.microsoft.com/en-US/evalcenter/jj554510.aspx?wt.mc_id=MEC_132_1_4. The suggested route with the evaluation copy is to create a virtual machine or a bootable VHD. To learn how to create a bootable VHD read this article http://blogs.interknowlogy.com/2011/09/01/windows7bootablevhd/. To learn about creating a virtual machine read this article http://www.techspot.com/guides/503-windows-8-virtual-machine/. Please be aware that the virtual machine and bootable VHD methods only available in Windows 7 (Home Premium or higher).

Tools and Resources

Once Windows 8 is installed visit http://dev.windows.com and http://msdn.microsoft.com/en-US/windows/apps/br229516.aspx to download Visual Studio 2012 and other tools and resources for developing for Windows 8.

Here is the slide deck and sample code from the presentation I gave last night (8/14/2012).

I had such a great time presenting. vNext is an amazing group! Very intelligent developers and quite creative too. It was fun talking about ideas for apps and speculating about the future.

Feedback is always welcome. If there is something you wish I had presented on but didn’t or if I just spent too much time in slides please let me know. Thank you vNext for letting me come and present on this new and exciting topic! Always a pleasure!

This post is somewhat related to my series WP7 Simplified. I have been writing the series based on an app codenamed LionHeart and just last night I was trying to get the PhoneDataProvider to save three (3) collections of complex objects. Up till now I’ve been regenerating my mock data each run. That’s OK until you want to start persisting data. Now that I’ve disabled the constant regen of data, I’ve uncovered a small mystery that confounded me for a few hours. So in hopes to save you some time here is what I found.

Basic Serialization Overview

Objects stored in IsolatedStorage are serialized. That means objects retrieved from IsolatedStorage are deserialized. IsolatedStorage uses the DataContractSerializer from WCF. I’m not sure if it’s the same, but that doesn’t matter right now. What that means is it relies on an opt-in pattern for objects to be serialized. Objects that are to be serialized but be adorned with the DataContract attribute and all properties that need to be serialized need to be public, have a getter and a setter, and be adorned with the DataMember attribute. That’s a lot of annoying attribute maintenance if you ask me. Luckily, Windows Phone 7 automatically assumes that each class is adorned with DataContract and all public properties with a getter and a setter are adorned with DataMember so you don’t have to messy up your class with the actual attributes. Cool! Thanks, Windows Phone! However not everything is free. Each each type that will be stored in IsolatedStorage MUST have a public paramerterless (default) constructor. If inheritance is used and there are properties of the base type where derived types might be stored then the KnownType attribute MUST be applied to the base type referenced for all derived types.

The Problem and Fix

Now into the problem I ran into. If you are missing KnownType attributes when calling IsolatedStorageSettings.ApplicationSettings.Save() a SerializationException will be thrown. This is actually good because it tells you what to fix. However, if one of the types is missing a parameterless constructor the Save method will not throw any exceptions. Why is this? Because serialization does not require the parameterless constructor, but deserialization does. So, one might expect an exception when deserializing that object from IsolatedStorage. Deserialization does fail but only throws a KeyNotFoundException. That is absolutely NOT helpful. So I scoured the internet and came across this post discussing manual serializing and deserializing. Figuring it was something to do with my objects failing to serialize or deserialize I used the two methods from the sample for Serialize and Deserialize on each collection of objects that I was about to save to IsolatedStorage. Sure enough I found that I was missing a parameterless constructor and deserialize was failing. Once I fixed my object everything saved just fine.

Serialize, Deserialize, and TestSerialization methods:

public class PhoneDataProvider : IDataProvider
{
	private static string Serialize(object objectToSerialize)
	{
		using (MemoryStream ms = new MemoryStream())
		{
			DataContractSerializer serializer = new DataContractSerializer(objectToSerialize.GetType());
			serializer.WriteObject(ms, objectToSerialize);
			ms.Position = 0;
	
			using (StreamReader reader = new StreamReader(ms))
			{
				return reader.ReadToEnd();
			}
		}
	}
	
	private static T Deserialize<T>(string jsonString)
	{
		using (MemoryStream ms = new MemoryStream(Encoding.Unicode.GetBytes(jsonString)))
		{
			DataContractSerializer serializer = new DataContractSerializer(typeof(T));
			return (T)serializer.ReadObject(ms);
		}
	}
	
	private void TestSerialization<T>(T originalObject)
	{
		string serializedObject = Serialize(originalObject);
		T deserializedObject = Deserialize<T>(serializedObject);
	
		if (Equals(deserializedObject, default(T)))
		{
			throw new Exception();
		}
	}
}

Using TestSerialization:

public class PhoneDataProvider : IDataProvider
{
	public void SaveChanges()
	{
			#if DEBUG
			
			TestSerialization(_clients);
			TestSerialization(_sessionNotes);
			TestSerialization(_sessions);
			
			#endif
			
			SaveValue(CLIENTS_KEY, _clients);
			SaveValue(SESSION_NOTES_KEY, _sessionNotes);
			SaveValue(SESSIONS_KEY, _sessions);
	}
}

So now, only in DEBUG mode, each complex object graph is “validated” and then saved to IsolatedStorage. I love it when things finally work!