00:01Alright, guys. Welcome to the Building Applications for ArcGIS Runtime SDK for Windows Phone, part II.

00:05So this is really the advanced session for building Windows Phone-based applications using our SDK.

00:11My name is Rex Hansen, product lead for Microsoft clients at Esri.

00:16I'm joined by Eager Ip, lead dev. for Windows Phone, and Kylie Donia, the lead product engineer for Windows Phone as well.

00:30But we're going to get right to the demos as soon as we possibly can, so just a brief look at the agenda here.

00:36We're actually just going to do a quick discussion on Metro, just to get an idea of the new design interface...

00:38Alright, so I'm going to take us through just a brief intro.

00:41...or the design paradigm that really is the foundation for a lot of the application building...

00:47...building an application, designing an application for Windows Phone specifically...

00:51...and then also something that you're going to see in Windows 8 actually, too, so this might be interesting...

00:55...to get kind of a background on that.

00:57Something to keep in mind is that you might see some of the Metro design and the Metro workflow in the apps that are built today.

01:04So keep an eye out for that. It might be something to look for.

01:07Then we'll finish with a little Q&A on some of the stuff that we saw in the demo today.

01:13Now, if you go to Microsoft's site, they have a nice little PDF actually on the Metro design...

01:19...and the actual document itself is Metro, right.

01:23Minimalistic. They start off with a nice statement here that talks about Metro as our design language, right.

01:27We call it Metro because it's modern and clean.

01:32And so it's kind of interesting that the document itself is Metro.

01:34It's very minimalistic.

01:36It is also quite crisp.

01:39So really that kind of highlights a lot of the functionality that's...if we hit some of the details of what underlies Metro...

01:47...is it's not just a code name for, you know, the Windows Phone user experience and application design...

01:55...which emphasizes that clean, crisp user experience; intuitive; personal, right; deliberate.

02:03But it's made up of a variety of different components, right.

02:05And then all these components have something technical that backs them, right.

02:09So we have a set of themes.

02:10We start in the upper left. We have a set of themes.

02:12Really, these themes really work out to be a set of resources, right, a set of styles and templates that are actually used...

02:19...to really personalize the look and feel of an application that you build on Windows Phone.

02:23Same thing for Windows 8, a Windows 8 application, right.

02:26These are common themes, common threads that are used across application development in general for the Metro-style applications.

02:35Static resources, right.

02:36This is a technical way for actually working with those resources specifically.

02:40There's a common set of resources and schemes and styles that you can use.

02:44Page anatomy. Page anatomy applies to the Metro design, the look and feel by offering different layouts, right.

02:51So a panorama of pages, maybe working with a set of application tabs that have maybe a pivot experience...

02:59...and you might see that experience within, let's say, our ArcGIS application, it's in the marketplace.

03:05Basically, different ways of interacting with content, the clean, crisp content that happens to be in your app.

03:10You might have a single page utility app.

03:12So there's really a couple different types of Metro applications as far as page anatomy is designed.

03:21Within those pages, you might see something like a title, might see something like an application bar.

03:26That application bar might have menu items, right, and there's a sort of a refined standard for how that...

03:33...for how applications are built and how they flow.

03:36Next option here is animations and transitions.

03:38Really, this is a...if you're thinking about animation, it may be associated with a user interaction, but it's really local.

03:47It's defined to give the user feedback, but it needs to be responsive and effective, right, and clean.

03:54Basically trying to transition a user from one view to another might be a good animation...

04:00...to indicate that something's happening and be deliberate about it.

04:05The transition itself is usually a response to user action, right.

04:09So you're providing some sort of feedback to teach the user how to use the application, right.

04:15So this transition allows you to respond to a deliberate user action, right.

04:19And so that should be a common flow within the application within the Metro design experience.

04:25There's an execution model, and this is an underlying execution model for how the applications work, how they perform...

04:33...when they're active, when they're in the background, when they're actually a tombstoned...

04:36...and when they're brought back to the foreground, how they run in the background...

04:41...and what you have access to and what you can do.

04:44So working with the application in page state and persisting that application in page state.

04:49Working with application and page events, right, and being able to manage that within the tombstoning concept.

04:57Matter of fact, Eager, I think, is going to touch on the execution model in more detail here.

05:00We'll see a brief graph, what that looks like.

05:04And lastly, the form factor, right.

05:07So, in general, what we've seen with Windows Phone is we have a very standard...fairly standard form factor...

05:12...where we have a common set of hardware controls that we can assume are generally there, whether it happens to be a...

05:18...obviously a multitouch screen or working with a common set of buttons on the interface on the hardware...

05:24...the hardware device itself, an 800 by 400 pixel display, right.

05:29So there's some common characteristics of the form factor when working on a Windows Phone device.

05:40Obviously, just recently, with the Tango update, we're expanding that form factor to include devices that have...

05:51...maybe less resources or less functionality, lower-cost devices, right.

05:55So we can work with a device that has 256 megabytes of, you know, of RAM instead of requiring, let's say, 512.

06:03We can work with maybe flash storage, more flash storage, greater amounts of storage.

06:07There's usually an A-GPS or an accelerometer actually included as well.

06:11Optionally, you might see something like on a Mango device, you might see something, or a 75 device...

06:17...you might see something like a compass or a gyro.

06:19There's usually a camera involved.

06:21And so a lot of these devices are really sensors that can be used...

06:24...and you can discover and utilize within your application development experience...

06:29...to bring it all together to really package up really a single app that feels like a Metro-styled app, right.

06:36It's clean, crisp, effective, and responsive.

06:38So we're going to see a lot of this functionality in some of the apps that are going to be built today.

06:44Now there's really two apps, and I'm just going to do a brief I guess...actually, I'll let you guys introduce the app.

06:49I'll let the developers introduce the app, and so I'll move it over to Kylie, I believe, first.

06:55We're going to take a look at, really, a general audience app here at this point.

06:59I guess I'll just talk about this briefly to intro where we're coming from.

07:03Many cases, you're building an app that's not GIS-centric, right.

07:07You're not building an app where they want to see a map the first time they open up the app, right.

07:11So you're not a GIS analyst.

07:12You're not actually gathering information in the field, you're not out there...

07:15You know, you need to know where you are right now.

07:18A lot of times, with general audience apps, a bit more focused.

07:23So in this example, we're going to be talking about working with, let's say, a pizza company...

07:29...and we want to be able to provide the end user with the ability to discover how close...they want to make an order.

07:34They want to discover how close the location is that they're going to purchase the pizza is from.

07:38They don't necessarily need a map, right.

07:40But they're going to use logic that requires some spatial orientation.

07:44And so, there's...the general audience that's out there now, that, you know...

07:49...doesn't need to work with a map-centric application but can still leverage some of our controls and our functionality.

07:53So the idea here is that we want to be able to work within that general audience space...

07:56...but also handle situations where we're working with a true GIS, maybe it's a map-centric-based application.

08:03So we're going to take a look at both of those here.

08:04So I'm going to pass it over to Kylie to take a look at the general audience app.

08:09Alright. Thanks, Rex.

08:10So in this example, as Rex mentioned, what we're going to look at is an application if you wanted to, say, order a pizza.

08:18Let's go ahead and we'll open up the app, and the first thing a user...or a consumer wants to do when they order a pizza...

08:23...is set up what pizza they want to order.

08:25So we jump right on into that part of the workflow for them.

08:28We're not going to put them to a map, have them look at graphics first.

08:31If you're having a pizza delivered to your house, do you care the exact location of the branch?

08:36Do you want to see it on a map?

08:37No, not really.

08:39So let's go ahead and we set up a pizza.

08:41In this case, I put in some defaults so we can just go ahead and add that to our order.

08:45And we can add a second one as well.

08:46Let's make that one extra large, and let's give it some toppings.

08:49Let's go with pepperoni and sausage today.

08:53And, again, we can add that to our order.

08:56Now, in this case, I'm using a pivot, and we can see on the next part of the pivot here is how we place our order.

09:02So if we go ahead and swipe on over, we can choose with this order if we want it to be delivery or pickup.

09:08And we can choose what branch we want to use.

09:11And we can also review our order down at the bottom there. It has the foods that we've added.

09:16Now, if I want to do delivery, I probably want closest to my location, because it's going to be delivered, so just get...

09:22...I just want it to arrive as soon as possible.

09:24And I'm going to pick it up, there's a chance I'll want to do either a closest location or a favorite location...

09:31...say the one by a friend's house.

09:32So in this case, we've given the user some options.

09:35They can just use the closest location, which, as you can see here, the branch is already listed as the Palm Springs Airport branch...

09:42...because that's the closest to where we are right now.

09:45Or you can choose it from a map or from a drop-down.

09:47So let's look at the drop-down quickly.

09:49We see that there are four branches in this pizza parlor.

09:53And, you know what, I don't really want to look at that.

09:55I want to see it on the map.

09:57So we can, instead, decide...decide instead to pick it from the map, and you can see here that they can tap on a pizza joint...

10:03...and it will set it as their default.

10:06I'm going to go back to closest to my location, and if I had chosen a different branch than I'm closest to...

10:11...it would change right now what my branch is set to.

10:14So I'm ready to place my order.

10:16I've added some foods. I've chosen where. I've decided that I actually want to go pick this up.

10:21And I'm going to go ahead and place the order now.

10:24Still, unless they wanted to see a map to pick that branch, we haven't forced a map upon this user.

10:30They just want food.

10:32So we can fill out their information, and, again here, I've set some defaults just to save us from typing it all in.

10:39We can go ahead and place that order.

10:42At that time, we're switched to another part of the pivot.

10:45And in here, we're seeing the order, and, as you can see in red, the status of our pizza is changing.

10:50It was in the oven.

10:51Now it's being boxed, and it's actually ready for takeout.

10:56However, since this user is taking...doing takeout for this pizza, they do need to know where it is.

11:01They need the directions or the information about how to actually go pick up this pizza.

11:05And so from here, they can actually go ahead and look at those directions, and it'll generate the directions...

11:09...having total distances and time, information about all their turns, and for the user who likes to visualize the route they're going to take...

11:16...they can also view the map, and it will show the route that they should follow to get to their pizza.

11:26So that's a quick look at this app.

11:28Very consumer-based, as Rex mentioned.

11:30We're not looking at a map.

11:32We're not doing heavy GIS work.

11:34We're using location in a way that a consumer with a mobile device might need to use their location.

11:41Let's go ahead and look at some of the code for the API that's behind this application.

11:49So one of the first things that was done in the application was that it was able to make that drop-down of all the branches.

11:55Now to do that, I ran a query task, and I pointed it at, it's actually a hosted service that contains these four branches as points.

12:05I found all of the branches that are in that service, and then I just added those in...span that next part...

12:15...added each of those branches into a collection so that I could actually have the UI update based on what had been found.

12:22So if a new branch is added to the pizza company, they don't need to go release a new app.

12:27They update their hosted service that has all of their branches in it...

12:30...and the application would automatically then read in the new branch locations the next time it was used.

12:40Another task in the application that is using location behind the scenes is how it found the closest branch.

12:47Now to do that, again, we're using a task that is part of the API.

12:52We have the current location from the phone using the location service, and then we're going to use a closest facility task...

12:59...by saying our location as well as where all of the options of where we can get to...

13:04...it's able to find for us which of those branches is closest and return the information about that single closest branch.

13:15In this case, I know that my list of branches is going to match what's in my drop-down...

13:19...because I gathered them from that same service, and so I'm able to associate them back together and keep those in sync.

13:25So my selected branch is always a valid branch, and, at this time, it's now the closest branch.

13:37The other task that we're using from the API is finding directions.

13:42So in here, let me go up a little bit.

13:46Actually, that one got set up a little earlier in the code.

13:48So in here we set up a route task and, again, we just set some basic parameters like we do need the route back...

13:55...we want directions as well, what units to use, and if we're caring about time windows...

14:01...so there's a number of parameters that we can set up here.

14:04And then when the user actually clicks the button that says, Yes, give me directions, it just passes those...

14:14...it sets the parameters up that it...it already set most of them.

14:17It adds in where your start location is and where you're going to, and it solves a route between the two.

14:24Now one thing to mention really quick here, because I am kind of showing a lot of code really fast...

14:28...is that we are going to be providing all of the code for this demo after the session is over.

14:34They'll be available for download off one of the sites.

14:36So don't worry about all the details in the code. It will be available.

14:42So once we have solved the route, and we have a route passed back to us, we've set some parameters...

14:48...so that we can give the user back the distance and the time, as you saw at the top of that window.

14:54I've also taken each of the directions that returned, and in this case, I actually made its own type a direction class.

15:00So I was able to set the different pieces of the direction, about the time, the distance, and the actual text that goes with it.

15:06So that then in my UI, I was able to format that to best fit on a phone screen.

15:11The fitting is a little bit different than when you're working in a web API, because your real estate is a lot smaller.

15:16So that was one thing to keep in mind.

15:17We didn't want to just remember the list of directions but remember what each piece of direction was.

15:27So those are the key parts of the API that I was really using here.

15:30And let's take a look at the XAML as well.

15:34One thing that we did is made sure that we did some binding so that the UI isn't cluttered, right?

15:41As I mentioned, if you've said, I want this pizza delivered, you don't want directions.

15:45You don't want a map.

15:47So the option of viewing directions, viewing a map, those only appear if the person specified takeout.

15:52So that's one of the things to keep in mind on a phone, is that with limited real estate...

15:56...you really want to make the best use of that space that you do have.

16:01Another thing that I used in here from our API...let me scroll down a little bit...is called a child page.

16:10Now, when you saw the customer information up here, it kind of slid out nicely over the pivot.

16:16It didn't lose all my state in my pivot.

16:19It didn't...since it's a demo app, I didn't actually make full copies of all the data so that it would be tombstoned correctly...

16:26...and Eager's going to talk a bit more about those processes.

16:30But I just wanted it to work, and I didn't want to be switching pages.

16:33So we have this concept of a child page in the API, which basically is a little slider window...

16:38...that comes out on top without losing your context of where you're at in your application.

16:43I find it very helpful when I just want to present something really quickly or offer a choice without going away...

16:49...and doing something completely new.

16:56So those are the basics of this application.

16:58Again, I just want to reiterate that the focus is that it's not on a map.

17:03The API is more than just maps to display data.

17:06That's very important in a lot of applications. We'll use it.

17:09As you saw, we used it briefly even in this application.

17:12However, it doesn't have to be the focus.

17:14And so it's something to keep in mind when working on the phone, is that you can make these consumer-based apps...

17:19...and think about it how a user would want to use it as opposed to how a GIS analyst would approach the problem...

17:25...because sometimes you'll come up with a slightly different workflow and design.

17:30Alright. So turn it back over to Rex.

17:33Great. Thanks, Kylie. Good review there about a general audience app.

17:38Something to think about if...anyone here actually building a non-GIS-centric app, actually?

17:44Yeah. So something where you're just going to be plugging in some, I guess, some spatial capabilities at some point?

17:50Okay. Cool. Good deal.

17:54Great. So probably pretty commonplace for folks that just need to plug in...

17:57...and utilize some spatial operations or capabilities behind the scenes, but the next...so value across multiple platforms...

18:05...and multiple...for multiple...in multiple capacities.

18:10The next app that we're going to look at is more of a GIS-centric app, we're going to cover a lot of functionality...

18:19...in both the Windows Phone platform as well as the API, and it looks like...you guys good to go?

18:26Alright. So Eager's going to take it from here.

18:29I am testing the AML, actually.

18:32It's...

18:34Is it showing up?

18:35Shutting down by itself, so let's see.

18:43While we are waiting, I can switch on...

18:52So this is the second demo.

18:55It's about...Kylie's demo is about, like, a consumer-based app where you consume data.

19:02Like you grab it from line and then you run some GIS analysis to determine your best route, you know, where you are at.

19:10This app also does that because most of the time you need to grab some data first, right, to show your user...

19:17...and this one is on a service that do...recording some noise with your phone.

19:25So let's assume there are some microphone calibration experts that tell us, Hey, we know how the phone micro...

19:35...we can use the phone microphone to collect some sound data, and then we just say...

19:39...Okay, put it on the map and then let people, like, look at it to determine where your converse zone is...

19:47...or if you like party zone, right, you just...some, it's like an app; that way you can look at data and also collect data.

19:57So this is, lack of better name, is called noise crowdsourcing app.

20:06So let me try to see if it comes back to life.

20:11Is it OK or it's bad?

20:18You can see it? Alright.

20:22So what it does, the first screen, what it shows is pulled from a feature service similar to the pizza app we have.

20:29We have a hosted feature service on ArcGIS Online where it will show you the latest sound data collected so far...

20:38...and then what you can do is select one of them and then what it shows you like a general location of where it is...

20:47...the sound level is peak at 70, and then the average is 66, and it's...notice I use a component one control on it...

20:58...this little sound gauging control, and...let me show you another point location.

21:06This is a pivot control, showing the data of the specific point, and what you can also do is...

21:13...what it's doing now is just trying to find the zone that the noise level is lower than the selected point you have.

21:21So that's why you see this shape here.

21:25If you go tap on that, and see, because there are other data points around it, and they are louder than this selected point.

21:35So this is, little bit, an analysis map showing, Hey, you know, this is the area that is kind of like the zone of this sound level.

21:47So we did some advanced buffering and query to determine this area I'm showing on the map.

21:54And one thing you might notice, that it is the pivot, and generally you don't want to put a map on the pivot...

22:00...because it will conflict with the gesture.

22:03So I put a Zoom In and Zoom Out button here if you want to zoom in and zoom out, but if you really want to interact with the map...

22:13...by design is you tap on it and you will see the pivot kind of disappears, so now you're free to like use a gesture...

22:21...and then click the Back...tap the Back button and then we're back to the pivot mode.

22:27So it's one thing like pivot is...pivot and panorama is a very common natural design and it...you can, you know, make it work.

22:37So, but you just need to put some thinking about it, the interaction with it.

22:44So that's the query and analysis part of this app, and what I want to show you now is, we want to collect some data...

22:54...and so we tap on this Recording button, and if I press and hold the tap and hold button, it will start using the microphone...

23:04...and detect noise levels, sound level bites from the microphone.

23:09The algorithm is pretty arbitrary. It's not decibel. It's not, but it just shows you how it's done.

23:15We're using the microphone as the sensor.

23:17And then once I release it, it will say, Hey, you collected some sound data.

23:21We do the analysis and say, Hey, the peak level is 73, the average is 53; do you want to upload the data now?

23:28And I can say, OK, and what it does is...what it does now is starting the GPS location, and once I get the GPS location...

23:36...I would then push the data up to the feature service.

23:39So this is done.

23:41And if I go back to this list and hit Refresh...

23:47...you will see this data get submitted on the feature service and get pulled down onto your client.

23:58So this is pretty much basic and then we add some...it will be hard to see on the emulator.

24:05Something I want to show later in the code is, on the Windows Phone, there is something called reactive extension...

24:12...which is pretty cool for a programmer, and what it does here, I'm just collecting accelerometer data...

24:21...and when I do the shake, it will start...do the autorefresh itself.

24:26So it detects a shake and then invokes a command, and the command here is a refresh.

24:32Let me actually try to do this so that you can see it better.

24:44Waiting isn't fun...a GPS location.

24:48So on top is the progress indicator where you can data bind to some property, and I'm still locating GPS location...

24:58...so don't know what's happening.

25:05Yes. So that's pretty much what this app does.

25:09So let's dive into some code quickly and see how it's done.

25:22So in the first part of the demo, I'm just showing the same similar query as Kylie showed on her app.

25:28One thing new at the 3.0 - we're using the 3.0 prerelease API - is in the query, you can specify an order by fields.

25:36So that's why you will see I'm order by the date/time.

25:39There's a DateTime field in every record so then I don't have to do the sorting myself.

25:44You can...the query task, you can specify it.

25:49So pretty much pretty basic code, asynchronous programming, query task, run the task.

25:56Whenever it completes, then we populate the items.

26:02So that's query, and I'm sure you guys seen a lot of it, so let's dive into another thing about the secure...about the hosted service.

26:12One thing you can do with a service, a hosted service, you can secure it on ArcGIS Online, and new at...say new at 3.0...

26:23...the API 3.0 API, we provide the identity manager for you to easily set credential to access your service.

26:35So the way to do it is assign a challenge method, and the challenge method has this delegate signature to it...

26:44...and what it does, it's pretty simple.

26:47You can call...you're going to steal my user name and password...generate credential with your user name and password...

26:53...and once it's successful, it will get a callback here and then you just say, Let the identity manager know...

26:59...Hey, use this credential for this URL.

27:03So that's pretty straightforward.

27:06Of course, in a more event, or in a real app, you don't hard code the user name and password.

27:14You will have to store it in your app or, you know, pop up a dialog.

27:18So there will be, you know, little more work to be done to provide a user experience, but this code just shows you...

27:25...this is new and you can easily use it.

27:30And one thing I mention is some of the token generation requires you to set a referrer header.

27:38So the identity manager provides a mechanism to do that.

27:44And a little trick on Windows Phone is, on every web request, the phone will actually stay attached to the referrer header...

27:56...which has this format.

27:58It will be files:Applications/Install and the product ID you specify in your app manifest right there.

28:12And don't try to hard code this if you're going to submit this app to the Marketplace...

28:17...because when the Marketplace publishes your app, it will change your ID.

28:23So this is a little code that helps you to figure out, read the XML file and then pick out the product ID for you.

28:34So you will have this code where we're going to...so you can look at it in detail how it's implemented.

28:42So that covers identity manager where you can access secure services.

28:50I should do that from the screen.

29:00So next I want to show...there were a couple times Kylie and Rex mentioned about the life cycle of the Windows Phone app...

29:07...which is, if you come from the Silverlight development or other OSs, which is something I think it's new and different...

29:18...that you have to be aware of.

29:23So to track those events...so an app when you first start it from the Start screen, the launching event will be fired...

29:35...but the recommendation is, don't do too much in it, because that's why, otherwise, your app will take a while to start...

29:44...and it's not responsive.

29:47So there are different strategies you can use, like we'll have to wait till maybe the first map page, I mean, first page to be loaded...

29:53...then you start doing...grabbing your data. So that's one tip.

30:03And when the app closes, that means when the user taps the Back button...

30:11...when you are on the first page of your app, then the app is closed and exit.

30:17If you're using the Silverlight flavor of Windows Phone development, you cannot call, there's no...

30:25...you cannot call Exit to exit your app at any time.

30:28So keep that in mind.

30:30The only way that actually the app exits is when the user taps the Back button on the first page of your app.

30:39But there's another trick if you throw in unhandled exception, the app will close, but I don't think that is recommended.

30:47So, but in a simpler world, that would be perfect.

30:51Launching and exit, great.

30:53But on a phone is multitasking, you know. You may get a phone call or you might be in the middle of something...

30:59...you want to go to...start sending an e-mail or something.

31:04So what it does is, before Mango, all the apps will get tombstoned.

31:11What tombstone does basically, actually what it means is your app, the process is killed, it's terminated.

31:20But when the user comes back to your app through the Back button, the back stacking, the guidance is...

31:27...you have to make it feel like actually the user hasn't left the app.

31:34So there are two other events to check, to track.

31:38One is Deactivated.

31:39So whenever the user taps the Start, Windows Start screen, or get a phone call, or, you know, they sort of decide to use the camera...

31:47...your app got deactivated, and that's where you need to store transient data and also any application cross section data too...

31:59...because your app might never...your app might get relaunched again from the home screen...

32:05...and then the launching process will restart.

32:08So Deactivated is your last call to cache data when the user leaves the app by using...through tombstoning...

32:21...or when they switch over to another app.

32:25So once the app gets deactivated and the user comes back to the app, before Mango, all the apps get tombstoned...

32:34...and then restore from tombstone, like what I said. It's because the app...the process got killed...

32:40...and then you have to reestablish all...rehydrate all the data yourself.

32:46Usually you will store your data into the application state object...

32:52...but after Mango, there's a state...they have a new function, an IT feature called fast app switching.

32:58So what it does is, when the user taps the Home button, your app got pushed to the background.

33:07So it's still running, but it's not in the foreground.

33:11So all your memory and state is preserved as if you haven't left the app.

33:16So then when a user comes back to your app, you don't need to do much, like...

33:21...because basically all the memory and the state is restored for you.

33:25But, in case, when it actually got tombstoned, then you need to like load the data again.

33:31And there's a flag for you to check whether or not the app gets actually tombstoned or gets dormant...

33:38...which is not killed but it's just pushed into the background.

33:44So these are the events to look for and to...for the life...to maintain the life cycle of your application.

33:58And one thing we learned during writing the ArcGIS app is, you shouldn't try to store large data on the application state.

34:12Your app will get...when your app gets dormant, you won't see any message...

34:18...but actually there's some unhandled exception gets thrown...

34:21...but you won't see it even though you put a message box in the UnhandledException event...

34:27...and then the mysterious part for a user is when you come back to the app, [unintelligible] dormant...

34:33...you see Resuming... and then like a second later and then your app just closes without any warning.

34:39So we were trying to figure out like, what's happening, what's going on?

34:42We don't...we want the debug information, and then we found out what happened is...

34:52...in the Windows Phone ArcGIS app, we are storing some attachments, a lot of photos...

34:57...and then we are storing in the state, and if you run this code on deactivation, basically we throw an exception...

35:07...but this exception got silent because your app got dormant, and then when you come back, you're like...

35:13...I don't know what we did. What's going on?

35:15Then we did some...a bunch of things, look at different things, and then we finally figure out actually...

35:19...because the exception is pretty ambiguous, is a calm exception, which generally for Windows Phone development...

35:28...you don't expect to see calm exceptions, and you don't want to see calm exception because it's native code.

35:35So one trick, what we find out is, it's always a good idea in your UnhandledException handler...

35:43...that we...you just cache and serialize any exception thrown, because the message box when the app goes dormant...

35:52...message box won't show, so you won't see it.

35:55So it was a good idea that, you know, cache it and maybe put a debugger if statement there, if the debugger is attached then...

36:04...or in the debugging configuration just for you to troubleshoot, you know, during your development cycle.

36:09So track that and then at...you can later on sometime when the app relaunches again show, hey, there's exception thrown last time.

36:21At least you can see some information.

36:24Another trick you don't have to show in the app is I think you can use the isolated storage explorer...

36:28...so you can just grab this file and then just look at it.

36:32So it's a little...application life cycle is tricky, depending on your app, and you will find surprises like this...

36:41...and this is one thing we did to find out what's happening.

36:49Okay, so next.

36:55So in the app, you will see we collect some sound data using the microphone, and then once we collected the buffer...

37:06...we will turn on the GPS and collect some...collect your location and then submit it to the feature service.

37:15So one thing we learned from developing the ArcGIS app, same time, is there is a precision setting on your GeoCoordinateWatcher...

37:30...so generally when you do tracking, you want to use high.

37:33That will consume more battery power.

37:35It will take longer to start up.

37:40Keep that in mind.

37:41And also, it will be nice to set a movement threshold, and here I set it to 20 meters.

37:47I don't care about high precision, and if you want really high precision, we set it to 5 in the app...

37:55...but I don't think the phone can get any better, so we set it to 5.

37:58So what it does is, only when you move 5 meters from...well, 20 meters in this case, from your last location...

38:06...then you will get the PositionChanged event.

38:08So you won't get constant firing.

38:10If you don't set this movement threshold up, you will get an event fire every second.

38:17So one thing to keep in mind, you know, is initialize GPS parameters appropriately for your app.

38:23And another scenario, like, if you want just to use a general search application to find your general vicinity...

38:31...you don't need to use the high accuracy.

38:33You should use the default accuracy so then you consume less battery power and it's faster.

38:39Another thing we learned is try to have only one instance of GeoCoordinateWatcher in your app...

38:45...because if you have multiple ones and they have different parameters and settings, it kind of conflict each other...

38:55And one last thing is, it's also...always a good idea to check the time stamp of your geoposition returned by the PositionChanged event.

39:08What happens, we found if you have turned on your GPS earlier on in a different location...

39:15...and then you move to your current location and then you turn on the GPS again, sometimes what it does...

39:25...it will give you actually the last position right away, say, Hey, this is the position...

39:30...but, which...I call it stale location, because it might be accurate, depends on how far you've moved from your last location...

39:37...but if you check the time stamp, try to weed out location that is not current, is also a good practice for...

39:48...especially for GIS workflow, mostly you want, you know, you don't want a stale location. It's wrong.

39:55One last thing we learned about while programming the GPS layer is, you guys should know there's the emulator.

40:03I think Kylie kind of showed the emulator, and it's good...

40:11...to simulate location, but it doesn't have any accuracy set to each point.

40:18And also, if you want to task between high accuracy and default accuracy as I mentioned, there's no facility here to say...

40:27...Hey...to detect that scenario.

40:32Because one thing we found while developing the app is, well, somehow the setting got...didn't get set to high...

40:39...and then we were walking around and say, Why the GPS layer is way off?

40:43We're like, what's happening?

40:45And then later...and then if I test it on the emulator, of course, there's no different...

40:49...because we'll report the location where you click, but when you're in the field, if you don't have the accuracy set to high...

40:58...your location would be maybe based on your cell tower, so it will be off and then you try and figure out, Hey, what's going on?

41:07So in the field it doesn't work and, you know, when I'm debugging sitting in the office, it works fine...

41:16...and so, it's one thing to keep in mind; it's like, keep track of your GPS parameter settings on the phone.

41:31So let's...and if you're familiar with...and one more thing, after...right after we got the GPS location...

41:39...we just submit the graphic to the feature service, and I'm not going over the detail on how it's done...

41:47...because it's basic API call and nothing fancy, nothing special.

41:51We just create a graphic and call SaveEdits and add to the graphic collection to the layer.

42:07So let's do something fun.

42:13I'm going to show you one more thing before that.

42:17New, I think 2.4...before 2.4 when you have your own graphics layer and when you add graphics...

42:24...you have to make sure the graphic is the same spatial reference as all the other graphics.

42:30At 2.3, I believe, 2.4, 2.3, there's a new property in your graphics layer where you can specify the projection service...

42:42...and what it does, it, the class, you have to implement it yourself as...you have to implement IProjectionService.

42:51What it does is it will...when you add a graphic that's in a different spatial reference as the graphics layer...

42:58...it will call your projection service and say, Hey, you have to reproject it for display of the layer.

43:05So then you don't have to change your...if you don't have to bind to your graphic stores and you want to keep the original data...

43:12...this is a good way that, you know, you don't change your model or your model data, but for the display, it will still work.

43:22And then one note that if your...I think at 2.3, if you have geographic and web Mercator coordinate system thing...

43:32...it will automatically reproject it for you so that you don't have to do any work.

43:35So if you're sure your layer and your data is between, you know, is either on geographic WGS84...

43:44...or the web Mercator coordinate system, then you don't need to worry about using...implementing your own projection service.

43:53But this guy, the source code will be available, what it does is, it will try and use the client-side projection, if possible...

44:05...otherwise, we have to send it to the server using the geometry service.

44:15So one thing I'm trying to show on the AML is using the accelerometer to detect a shake...

44:24...and then once, you know, finish shaking, I will do the automatic update.

44:30So I am using something that you don't have to download separately.

44:35It's already available on the phone.

44:38It's called reactive extension, so the name space is like Microsoft.Phone.Reactive...

44:45...and this, what it does is accelerometer, you can set it up and then just listening to the event...

44:52...and if you do some WHERE clause and say, Oh, if the accelerometer reading exceeds this value...

45:04...then I'm going to report it to you, say, Hey, I'm going to push the message saying...

45:08...Hey, something happened. So then if you subscribe to this observable collection...

45:19...whenever there's a value generated based on this event, you will receive a message and then to handle it...

45:27...you can just call subscribe to this event, I mean, subscribe to this...yeah, you can call observation and then do whatever you want.

45:37So that's how I implement it.

45:40So reactive extension is pretty fun on the phone.

45:44So this is just one example how it's done, and it's pretty short and sweet.

45:51So one last thing actually I want to show you about is on the phone, there's something called push notification...

46:03...and let me set up real quick on...so what it does is, for example, if I have...

46:13...someone else has a phone and then I collect some data.

46:16I want the update to be automatic.

46:18I don't want to do it myself manually by pushing a button.

46:23So what you do is, you set up a push notification service and then your phone has to subscribe to it...

46:32...and then you open the channel to the push notification service, so instead of you constantly pulling from the web service...

46:38...where it does, Microsoft provides this push notification server where you have a web service talk to it and then say...

46:44...Hey, I have something has changed then push it over to the phone.

46:49So that's basically a similar, I think, iOS and even Android, yeah...

46:52...on all smartphone platforms they have some kind of push notification system here.

46:58And I think we have time may just to show how it works.

47:06Let me do a little trick here.

47:14Only thing I need to change is, instead of adding data through the client code, I'm going to add the data through this cloud service...

47:25...a WCCF service, which knows how to talk to the...do the push notification.

47:33And let me...so what I'm going to show you that I have the emulator up and then I have this phone up which is going to collect the data...

47:48...so let me deploy this to the phone as well.

48:09So what I am going to do is start the emulator here and what I'm going to do, you won't see on the screen...

48:23...is I'm going to collect a sound data, and I'm going to make it really loud this time because you guys are really quiet.

48:30So [bells ringing]. It doesn't do that [bells ringing].

48:36Okay. So I collect a really loud data point, and it shows up.

48:46So that's how push notification works, and I think this is one thing we haven't explored a lot in ArcGIS app, but it's...

48:53Anargyros, actually he did a lot of the backbone for this demo, and I think it's something...I think it's really useful.

49:01I think a lot of people when they download the app, they care about there's some push notification enabled.

49:05So I want to be notified when something happens, right?

49:09So we got the code for you.

49:12I think we are running out of time but, so to see how it's done. So that's pretty much what I have.

49:26Does this actually show the...it's alright if it doesn't, yeah. Okay.

49:32Alright, so there are no additional slides actually on that one.

49:34So thanks, Eager, actually great demo.

49:39She's showcasing a lot of different functionality, obviously touching on a variety of the different...

49:43...the new functionality that's going into ArcGIS Server 10.1 as well as a lot of the platform-specific functionality...

49:48...looking at some Metro design, looking at some execution model capabilities, some...working with some sensors.

49:53Obviously another capability is...she mentioned Anargyros.

49:56Anargyros is another rock star developer, actually, on the Windows Phone team as well.

50:03He's handing out surveys over there. Good stuff.

50:08It's personal service here. Actually, it's small enough so we get personal service.

50:13At this stage, what I'd like to do is open up for questions.