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Many thanks to the attendees of my presentation tonight covering Developing Cloud Enabled Windows Phone Applications with Windows Azure.  I apologize once again for the technical network-related gremlins that decided to attack us tonight…hopefully the workaround covered the necessary ground and everyone was able to see the concepts I was trying to show.

As promised, I have posted the content for the presentation here.  This includes the slide deck with the various resource links, as well as the final project.  As I mentioned, I have “sanitized” the configuration of the project to omit my specific Access Control (ACS) settings.  This involved changing the AccessControlResources.xaml file in the phone project and the Web.config file in the web role project.  Look for the text [your-xxx-here] for where to substitute your own ACS information.

Because the network issues prevented us from accessing the NuGet site or repository, I wanted to be sure to list the packages that were used in these projects:

I would like to thank the organizers and attendees of the recent 16th (wow!) Boston Code Camp where I did a talk on Developing Cloud-Enabled Windows Phone Applications with Windows Azure – and special thanks to everyone who stuck it out once the snow started falling in order to catch my talk.  Obviously, it took longer than expected to get this content posted – Nashua got hit especially hard by the storm, including a 75% city-wide power outage the day following the Code Camp event, along with accompanying telecom and even cellular outages.  I am happy to say that I finally got my power turned back on mid-week, and am slowly but surely digging out of the mountain of backlog that piled up during the multi-day outage.

The content can be found here.  Because I demoed ACS, some of the items that are placed in the project would normally reference my “real” Azure account…they have been removed and replaced with the phrase “YOUR CONTENT HERE.”  You will need to replace these values with your own from the Azure ACS management portal in order to be able to run the provided code.  Also, in order to use the Azure Emulator, be sure to run Visual Studio in Admin mode when working with this project.

Many thanks to the organizers and attendees of the Boston Azure User Group where I had the chance to speak this past week on Developing Cloud-Enabled Windows Phone Applications with Windows Azure.  I hope everyone who attended enjoyed the presentation as much as I enjoyed doing it.  I certainly appreciate everybody having stuck through considering the A/C glitch causing the room temperature to get a little uncomfortable.

Speaking of weather, I think my house is now as prepared as it is going to be for the upcoming arrival of hurricane Irene to New Hampshire…I really didn’t think I’d be dealing with these anymore after my 15 years in Florida – that we “paid our dues” in New England with our annual rounds of Nor’easters and other winter “fun.”  Nonetheless, the slide deck and code from the presentation have been posted, and can be found here.

The sample code is broken into 5 parts across 4 solutions as follows:

1. Membership (Windows Azure Toolkit for Windows Phone)
2. Storage (Windows Azure Toolkit for Windows Phone)
3. Notification Services (Windows Azure Toolkit for Windows Phone)
4. AppFabric Service Bus
5. OData (Azure Data Marketplace and SQL Azure)

Key “markers” have been placed into the code files as comments that start with the word “NOTE” (a handy way to see *most* of them is to make use of the Visual Studio Task List pane, however, there are a few in the config files that don’t get picked up by this pane.)  The code has been sanitized to point to local storage and/or to remove any keys I had put in that were specific to the sites and accounts I was using for the demo.  Please substitute your own private values where necessary.

I have uploaded the content from my talks at yesterday’s (5/7/2011) New England Code Camp 15.  I had two talks – Introduction to Windows Phone 7 Development with Silverlight and Advanced Windows Phone 7 Development with Silverlight.  The content for my first talk can be found here, and the content for the second talk can be found here.  The content includes:

• Presentation slides, which include the reference links I mentioned during the talk.
• The sample code.  In the second presentation I discussed the Bing Maps control.  I have removed my Map Key and replaced it with the text “YOUR_KEY_HERE.”  To remove the licensing warning that appears when running the project, be sure to get an application key from the Bing Maps Developer Portal and replace the temporary text.

After having done various phone talks over the past year, I decided I needed to overhaul the content prior to this presentation.  This was done both in order to relate the contents of the presentation to something that more closely resembled an actual app, as well as in anticipation of including the upcoming “Mango” content.  I think the presentation got closer on those fronts, but it still needs some tuning (especially the first half, which ran a bit long…my apologies to the attendees for having to rush through some of the material.)

I have also discovered an interesting defect in the application that occurred after adding the code to handle saving page-state when the app is tombstoned.  What happens is that the closing of the DatePicker control (from the Silverlight for Windows Phone Toolkit) sets the value of the property before an OnNavigatedTo event is called, which resets the value to what was serialized when the control first appears.  The net result is that the DatePicker control ceases to change the date.  I included a quick fix for this in the code published above, and will be taking a deeper look at this control in the coming days, with a more thorough post to follow.

While I am actively working on adding new functionality to the LightTouch library (such as adding the Pinch Gesture to bring parity with the GestureListener for Windows Phone from the Silverlight for Windows Phone Toolkit) for an upcoming release, a couple of issues came to light that made adding a new release appropriate.  As the title of this post suggests, these issues relate to support for touch in Popups (especially ChildWindow controls) and for controls where different layers of the control’s visual tree make use of different behaviors.

Support for Popups / Child Windows

At the heart of LightTouch is the Manipulation2DBehavior.  Much of the functionality behind this behavior is discussed here.  One of the basic methods’ responsibilities is to determine, based on the coordinates of the touch event, what controls are under that point and which of those controls have the Manipulation2DBehavior attached.  To do this lookup, the VisualTreeHelper.FindElementsInHostCoordinates function is used, with Application.Current.RootVisual supplied for the relative UIElement.  This is where difficulty with popups occurred.  Popup controls exist outside of the Visual Tree of the application’s RootVisual.  This can be seen in the following UI, with its Visual Tree as reported by Silverlight Spy.  Note how the Popup control appears as a sibling to the MainPage element.

So in order to locate the controls with behaviors in the popup, we have to use the Popup as the relative UIElement for the call to VisualTreeHelper.FindElementsInHostCoordinates.  Now to find the popup in the Visual Tree…this can be accomplished with the VisualTreeHelper.GetOpenPopups call.  Unfortunately, this call does not document how the list is populated relative to the Z-order of the ChildWindow (in case multiple ChildWindows are being displayed, issues of UI-propriety with this approach notwithstanding.)  Empirically, it seems that the topmost child window (if present) is the first in the list, so if any ChildWindows are being shown, we locate the first one in the list, and use it as the argument to FindElementsInHostCoordinates.  From there on, things progress as they had previously.

Supporting “Layers”

Shrek: “NO!  Layers.  Onions have layers.  Ogres have layers.   Onions have layers.  You get it?  We both have layers”
Donkey: “Oh, you both have layers.  Oh.  You know, not everybody likes onions.  What about cake?  Everybody loves cake!”
- Shrek (2001)

So what do I mean about layers?  In this case, I am referring to a situation where multiple related controls under a given point in a visual tree have Manipulation Behaviors attached.  An example would be a ListBox control with the ListBoxTouchScrollBehavior attached, and the underlying data template for the items in the list box having a GestureListener attached with a handler for a DoubleTap event.  The original implementation stopped at the first matching behavior, resulting in the ListBox scrolling, but ignoring the DoubleTap event.  The new implementation now identifies and processes all Manipulations under the given touch point.  This is similar to a Bubbling event, with a couple of key differences.  First, there is no notion of “handled.”  Second, the relationships do not have to exist in common branches of the same visual tree.

Available for Download

The latest code is up on CodePlex and the Alpha-2 release has been built based on these changes, which can be downloaded here.  I hope people find it helpful.

I have uploaded the content from my Introduction to Windows Phone 7 Development with Silverlight talk at the New Hampshire .Net Seacoast User Group meeting last night in Portsmouth. The content can be found here, and includes:

• Presentation slides, which include the reference links I mentioned during the talk.
• The sample code, broken into 2 projects. Because the Notification Services portion of the talk adds extra projects to the solution ad is a little more complex to build and launch, that portion has been broken out into its own separate zip file.

For the Notification Services portion of the demo, the web project should be launched first, followed by the phone project (since the phone app calls the web site to register its URL for receiving notifications.) If the solution is run with the web project set as the default start project, the application bits do get deployed to the phone, but the debugger is not hooked up (unless multiple startup projects are used.) If debugging of the phone app is desired, it can be achieved by right clicking on the phone project and selecting Debug / Start New Instance. Also, this time the Notification Services demo includes the Push Notification Server-Side Helper recipe.

As usual, I have “sanitized” the uploaded code content by removing my personal Bing Maps application key. For information on how to obtain your own map key, please check out the Bing Maps Developer Portal.

I have also added a project that  shows the technique for “immediately” updating the application’s tile via a temporary Notification Services endpoint.  This is based on the code first presented here. 

The posted Slide Deck includes the slides that call out new content in the upcoming “Mango” release of WP7, and I have edited one slide to include one IMPORTANT new addition to the phone SDK that I forgot to previously include – support for Sockets.

Many thanks to Pat Tormey for inviting me to be the inaugural speaker for this new user group, as well as to Mark Mullin and Global Relief Technologies for providing a great site.  Also many thanks are deserved by the attendees, who asked some of the best questions I have gotten since I started doing these talks.

As is often the case when big events happen, sometimes some important announcements can get overlooked and/or overshadowed.  Mix 2011 certainly featured big news, including Silverlight 5 Beta, the Windows Phone 7.5 features, IE10, and the latest in the MVC framework.  However, in all of the hoopla, the release of the SP1 refresh of the Microsoft Visual Studio Async CTP SP1 Refresh, as well as some of the important changes, may have gone unnoticed.

There are a few important things to note regarding the Async CTP Refresh:

• It includes an “As-Is” Go-Live license for use in production environments (albeit with some stern warnings about why you should really consider NOT using it in production code.)
• It includes support for .Net, Silverlight 4, and Windows Phone 7.0.

Let me restate that last point.  The Async CTP works with Windows Phone 7 today.  No need to wait for the Mango update.

Now Just “await” a Minute…

As a CTP, and with the “As Is” license, there is no guarantee that this will eventually make it into the framework, and even if it does, it may take a very different form.  That being said, it is a great opportunity to see where things are headed and to offer feedback to the development team as to how to best shape this functionality to be as useful as it can be. 

That’s Nice.  How Long do I have to “await” to See Some Code?

So what do the Async tools bring to the table?  Among other things, it allows asynchronous code to be written without the “disruption” that currently occurs when that is being done today.  While a full discussion of asynchrony and the problems it solves and the new ones it presents are beyond the scope of this discussion, some brief coverage is merited.  Writing synchronous code today follows the pattern of “do something, wait for it to finish, then proceed.”  Altering this to be asynchronous (often) changes the pattern either the Asynchronous Programming Model/APM (“Call BeginXXX to start the operation, then EndXXX to wait for it to be completed”) or to the Event-Asynchronous Pattern/EAP (“start doing something, and raise an event that I am listening for when you are done.”)  When the completion of one asynchronous operation needs to trigger another one, code can get complicated and messy.  This situation is particularly apparent to those who use Silverlight and the related Silverlight for Windows Phone, as all I/O operations in Silverlight are inherently asynchronous.  The Async CTP brings a third model – the Task-based Asynchronous Pattern/TAP. 

The TAP model features the use of the async and await keywords to allow asynchronous code to be written in a much more linear fashion.  Under the covers, the compiler will generate all of the necessary “goo”, allowing the development to focus on the problem at a higher level.  The following code may help to visualize what this all means.

In the code that follows, a WebClient is spun up to return the data at a given URL.  The number of bytes in that data is returned as the result of the function.  This is the synchronous version of the code.

Note that this code blocks the UI when called, and cannot be used in Silverlight or Silverlight for Windows Phone applications.  So what if you don’t want to block the UI while retrieving the information (or better yet, what if you cannot, as is the case with Silverlight?)  Bring in asynchrony, but notice how it changes the nature of the function.  Where the desire had been to call a function to retrieve a result, now the function is called to eventually signal a response, which must be subscribed to by the calling code.

This is somewhat compressed and contained when inline lambda expressions are brought to bear, but the fundamental problem still exists.  The function has been modified because of its asynchronous implementation. 

Now lets see how using the Async tools change things. 

Note that the functions now much more closely resemble the initial synchronous version. 

I’m Tired of “awaiting”.  Get Me the Bits.

This was just a light overview.  There are many other combinations and applications for the TAP.  Hopefully, this was enough to pique some curiosity.  If interested, the download for the Microsoft Visual Studio Async CTP SP1 Refresh is available at http://msdn.microsoft.com/en-us/vstudio/async.  This includes documentation, samples, and walkthroughs.  The tools require Visual Studio 2010 SP1.  Check out Eric Lippert’s announcement of the release (and additional links) at http://blogs.msdn.com/b/ericlippert/archive/2011/04/13/refreshing-the-async-ctp.aspx.

I have uploaded the content from my Introduction to Windows Phone 7 Development with Silverlight talk at the Tech Valley .Net User Group meeting last night in Albany. The content can be found here, and includes:

• Presentation slides, which include the reference links I mentioned during the talk.
• The sample code, broken into 2 projects. Because the Notification Services portion of the talk adds extra projects to the solution ad is a little more complex to build and launch, that portion has been broken out into its own separate zip file.

For the Notification Services portion of the demo, the web project should be launched first, followed by the phone project (since the phone app calls the web site to register its URL for receiving notifications.) If the solution is run with the web project set as the default start project, the application bits do get deployed to the phone, but the debugger is not hooked up (unless multiple startup projects are used.) If debugging of the phone app is desired, it can be achieved by right clicking on the phone project and selecting Debug / Start New Instance. Also, this time the Notification Services demo includes the Push Notification Server-Side Helper recipe.

As usual, I have “sanitized” the uploaded code content by removing my personal Bing Maps application key. For information on how to obtain your own map key, please check out the Bing Maps Developer Portal.

With all due respect to Steve Martin’s hilarious portrayal of Navin R. Johnson and his quest for “his special purpose” in 1979′s The Jerk. Tonight Microsoft released the Windows Phone Developer Tools January 2011 Update, which can be downloaded here. In addition to the content in the new tools, there’s also some interesting other news concerning the availability of unsubsidized phones for purchase at Zones.com.

The New Tools

The big update item is the addition of Copy & Paste functionality. All TextBox and PasswordBox controls now get Copy and Paste functionality. This apparently applies to applications already in the Marketplace – once the update has been applied to the phone, Copy & Paste is available. The new behavior is bi-directionally compatible…controls within apps already on phones will automatically get Copy & Paste when the phone is upgraded, and apps compiled against the new Developer Tools will not misbehave on phones that have not yet received the update.

Note – the update is only for the developer tools – it is not yet available to be applied to devices – unlocked developer devices or otherwise. It only works in the Emulator.

Looking at the Copy & Paste behavior, when a TextBox has focus and a word is tapped, it gets a special highlight and the Copy Button appears. This works both with the mouse clicking in the emulator, as well as using touch when testing on a touch-enabled PC. There is no option for selecting portions of a word (eg to just select the “op” in the word “Copy”.) That last caveat is probably not that big of a deal, as selecting portions of a word on a touch device the size of a phone probably requires too much finesse. Multiple words can be selected – which is discussed below.

Figure 1- Selecting a Word and Displaying the Copy Button

To select multiple words, once the first word has been selected, it pressing and dragging on either edge allows the amount of text to be copied (in full word increments) to be adjusted

Figure 2- Extending the Selection to Multiple Words

Once text has been copied, a special Paste Button appears over the top of the onscreen keyboard (AKA Software Input Panel or SIP.) This is the same area where type-ahead suggestions appear.

Figure 3- The Paste Button on the Standard (US) SIP

Figure 4- The Paste Button on the SIP with InputScope Set to “TelephoneNumber”

In addition to TextBox and PasswordBox controls, the Copy & Paste functionality extends to controls that internally make use of TextBox controls, such as the Silverlight for Windows Phone Toolkit implementation of the AutoComplete Box. It also works for Text Input controls in web pages displayed in the WebBrowser control or in the phone’s Web Browser. However, in the WebBrowser control, the Copy Button can tend to “wander” a little bit…

Figure 5- Copy & Paste Controls in the Web Browser Control. Note the Odd Copy Button Placement

Paste is fairly straightforward. Select any control where the SIP appears and select the Paste Button. Paste is “single-shot” – there does not appear to be multiple Paste. Once the Paste Button has been pressed, the “clipboard” content is pasted into the target location, and the Paste Button is removed.

Two more quick notes about Copy & Paste:

1. The “clipboard” persists outside of the application, so copied text can be used in other phone applications (for example, copying a Url from an application and pasting it into the browser’s address bar.) This also includes Tombstoning.
2. The update also includes updates to the Pivot and Panorama controls. The update is for when TextBox controls have been added to panels within these controls, and aims to suppress inadvertent swipes when trying to copy text. Apps that have TextBoxes in Pivot or Panorama controls will need to be recompiled to get this change (they will still have Copy & Paste, though there may be some usability issues…)
   1. (Yes, the issue Jeff saw with Tombstoning is still there…)

Other Stuff in the New Tools

Other than the Copy & Paste feature, there are a couple of other things included with the update:

• The Bing Maps Control has been updated for better gesture responsiveness
• The update includes the Windows Phone Connect Tool, which is installed at <x86_ProgramFilesDir>\Microsoft SDKs\Windows Phone\v7.0\Tools\WPConnect. This tool can be used to connect a device for debugging when Zune is not running, which is necessary when debugging apps that use the media APIs.
• The update includes the Windows Phone Capability Detection Tool, which is installed at <x86_ProgramFilesDir>\Microsoft SDKs\Windows Phone\v7.0\Tools\CapDetect. This tool is equivalent to the one used when applications are submitted to the Marketplace to inspect the app’s code so as to determine which capabilities are required by the app. These values are then used to replace the list in the app manifest. This tool can be used to preview what capabilities will be being detected before the app is submitted, in order to prevent issues like one (of admittedly several) issues seen by Shawn Wildermuth (see “Problem Part 4″) when an assembly that was inadvertently left in the application caused the app to report capabilities it actually didn’t need.

In addition to the tools, there is also a separate bug fix (VS10-KB2486994-x86.exe) that addresses a bug that existed whereby XAP files over 64MB could not be deployed by developers to physical devices for testing.

Issues with the Update

There is one known (at this time) defect with the update. Installing the update sets the default target for debugging Windows Phone Applications to be the “Windows Phone 7 Device”, even when a device is not installed. It is easy enough to change the value when Visual Studio barks at you, but it doesn’t “remember” the change, so it gets really old really fast.

Figure 6- The Default Debug Target for Phone Apps Changed to Windows Phone 7 Device

According to the Release Notes, the following steps are necessary in order to change this behavior (they work!)

1. Close all Visual Studio and Windows Phone Emulator instances.
   
2. Delete the contents of %LocalAppData%\Microsoft\Phone Tools\CoreCon.
   
3. Restart Visual Studio.
   

Purchasing Unsubsidized Phones

In addition to publishing these new tools, apparently Microsoft has entered into a partnership with zones.com to allow the purchase of WP7 phones without going through one of the wireless carriers and the associated contract. The phones are locked to a specific carrier (it is not possible to take the Samsung Focus to T-Mobile in the US, for example), but they do allow developers to obtain devices for testing. As of the time of this writing, there is mention on the site of a “coupon code” which can be applied for some kind of discount, but I have no other information about any such offers. There are currently 3 phones available for purchase – the AT&T-offered HTC Surround ($500) and Samsung Focus ($525), and the T-Mobile HTC HD7 ($500). The zones.com developer purchase portal can be found at http://www.zones.com/windowsphonedeveloperpurchase.