• Most importantly, a PowerShell script named Add-AppDevPackage.ps1 (and a folder with associated resources) that will install the app on a side load–capable machine. This process makes it easy to share your app with others without sharing your source code project. A good case for using this is if you hire others to thoroughly test your app. Running the PowerShell script installs the app very much like it would be from the Store, so if testers side-load on a machine where your app has not been installed before, it closely approximates a typical user’s environment. This way you can truly test the first-run experience of your app on a variety of devices. Planning: Can the App Be a Windows Store App? In a slight contradiction to this chapter’s title, the idea of “apps for everyone” doesn’t necessarily mean that every app can, in fact, be a Windows Store app. There are two sides to this: technical feasibility and meeting Store certification requirements. Technically, as we covered in Chapter 3, “App Anatomy and Page Navigation” and a few other places, Window Store apps run under certain conditions and restrictions. Here's a summary: • Windows Store apps always run in the app container and have no access to APIs that can openly access the file system or any other sensitive resource. • Sharing data between Windows Store apps always goes through the Share contract, the clipboard, or web services; local interprocess communication is not supported. (Local loopback is supported only on machines with developer licenses and will cause the app to be rejected from Store certification.) • Windows Store apps can use only the WinRT APIs along with a subset of Win32 and .NET APIs; apps written in HTML and JavaScript can also use the intrinsic HTML and JavaScript APIs provided by the app host. Any third-party libraries you use in the app must also use only these APIs. • Apps cannot install custom device drivers or anything else that affects the system, nor can apps customize their install process. • Only certain apps can run in the background, and for specific purposes, as we’ve seen in Chapter 10, “Media,” and Chapter 13, “Live Tiles, Notifications, the Lock Screen, and Background Tasks.” • Some UI interaction models aren’t appropriate for touch input, such as high precision CAD. Because Windows Store apps must support all forms of input, high precision apps either need to be redesigned for touch or should be implemented as a desktop app. • Windows Store apps run in one of four view states and cannot utilize overlapping windows. If any of these technical aspects would prevent you from writing the kind of app you want to write, then working with the Windows Store as your business location, if you will, is not really possible. For example, many development tools, network administration tools, file system utilities, antimalware utilities (that scan the whole hard drive), and database management systems must be implemented as 760
desktop applications and distributed through the Internet or other retail channels. 78 More generally, because Windows Store apps run full screen or with at most one other visible app, they are intended to be much more specifically focused on certain tasks. Apps that try to do too much—Swiss Army Knife apps, if you will—may end up feeling cumbersome or confusing. It’s good to hone the purpose of the app, as discussed in Planning Windows Store apps; otherwise you should probably implement a desktop app instead (for which there is still a very large market, mind you!). When planning any app, be sure to review the Windows 8 app certification requirements to understand whether the app you’re thinking about will be summarily rejected during the onboarding process. Examples include apps that contain gratuitous violence, hate, adult content, solicitations, and so forth, as well as apps that consume an inordinate amount of battery power, attempt to just repackage a website as an app, or clearly don’t add value to the Store as a whole. So, if you’re thinking to submit the next great bodily-functions-sound-effects app, you might think again. Also be aware that the Store policies can change over time, so be sure to check them anew before you start any new project. A final consideration is whether the Windows Store is itself available in a target market when you plan to release your app—the Store will be rolled out to different markets over time. Unfortunately, there is not a published schedule for that rollout; you'll need to watch for announcements. There might also be restrictions on whether you can submit an app to certain locales based on where you operate as a developer. This information is again best found on the Store developer portal. Planning for Monetization (or Not) Just as there are a number of reasons why you’re interested in creating apps in the first place, there are also a number of ways to fulfill your business goals. Will your app be completely free? Will it be free but supported by ads? Will it be paid, with or without a trial version? Will it involve in-app purchases? Each of these business models has its place, especially if you plan on releasing multiple apps. Furthermore, it’s likely that your business model or models will change over time as you improve your apps and respond to competition. In this section, we’ll explore at these different models and better understand how they relate to one another. 79 Remember in this whole context that licenses for apps and in-app purchases are granted to the user and will apply across up to five devices. This isn’t typically a concern for apps because the details are automatically handled by the Store—if the user attempts to install the app on a sixth device, Windows will instruct him or her to remove the app from a machine. 78 With developer tools, it’s feasible that a Windows Store app could itself provide an interpreted runtime environment for developing apps that would always run inside that tool. A Windows Store app cannot, however, directly produce another Windows Store app because the necessary packaging and deployment APIs are only available to desktop apps. 79 Another general overview that includes details on pricing can be found on Making money with your apps through the Windows Store on the Windows 8 Developer Blog. 761
1 99
Table of Contents Introduction ....
WinJS Tools for Pages and Page Navi
Chapter 6: Layout .................
Design Guidelines for Settings ....
Manipulating Audio and Video ......
Managing Secondary Tiles ..........
The User Profile (and the Lock Scre
The Windows Store APIs ............
Introduction Welcome, my friends, t
I'm also assuming that your interes
Acknowledgements In many ways, this
Support for developers, however, ca
technologies, including DirectX, XA
The upload process will walk you th
FIGURE 1-2 A typical app page in th
do this, I’m sure!). In a hotel,
The app host is more or less Intern
Sidebar: Mixed Language Apps Window
When snapped, on the other hand, ap
Capability Description Prompts for
Taking a Break, Getting Some Rest:
So you might say, “Well, I should
that the user has to configure the
Fortunately, the Windows Store dash
graphics called for in the design s
4. After Visual Studio churns for a
Add-AppxDevPackage. That batch file
package, whereas a single / refers
QuickStart #1: Here My Am! and an I
FIGURE 2-8 Snapped wireframe (left;
which we’ll instantiate a Bing ma
orientation, screen resolution, and
FIGURE 2-12 Full-screen landscape v
What this means is that, for the mo
Create the map (though the namespac
Next, in the second parameter to po
FIGURE 2-17 Setting the Location ca
Here we’re providing capturePhoto
the contract is an abstraction that
Extra Credit: Receiving Messages fr
Note that such apps might not be ab
Chapter 3 App Anatomy and Page Navi
content and controls from web servi
Such capabilities are blocked becau
Can you do any kind of dynamic page
appdata. This happens via Windows.S
I don’t know about you, but I rea
telling you to not use it! After al
App Activation First, let me congra
In the table, note that 80% scale t
Activation Code Paths As we saw in
splashScreen SplashScreen Contains
In truth, so long as the user keeps
Of course, setPromise ultimately do
previousExecutionState values are d
object to which you can add whateve
Because we stored lastPosition in s
FIGURE 3-9 The output of the Simple
What about launching from the previ
For all other details on this funct
The Navigation App Template, PageCo
(function () { "use strict"; WinJS.
}, ); if (that.pageElement.winContr
Sidebar: Helping Out IntelliSense I
thousands of items, where tapping a
Completing the Promises Story Whew!
mechanism on top of singular XHR op
The story of controls in Windows 8
Creating or instantiating HTML cont
Hyperlink href, target Link text L
defined as part of the WinJS.UI nam
Clearly, then, the bulk of the work
var element = document.getElementBy
This example is taken directly from
FIGURE 4-7 Expanding a WinJS contro
Flexbox -ms-[inline-]flexbox (value
Note Though not shown here, you can
For the ToggleSwitch, win-* classes
• If a WinJS.UI.Tooltip is gettin
Custom Control Examples To see thes
Between calendar.js and calendar.cs
]]> Whe
This would be appropriate if you cr
Two-way: essentially one-way bindin
The code for this can be found in T
Sidebar: Data-Binding Properties of
Implementing Two-Way Binding To imp
• oneTime A function that just lo
• Windows 8 apps have rich stylin
Collection Control Basics To seek t
indingList: bindingList, array: arr
Now while the ListView control in S
The header template in html/scenari
In the modified sample I changed na
} return groupCompareGlobalized(lef
a function instead of a declarative
var list = new WinJS.Binding.List()
data-win-options="{ itemDataSource:
e used anywhere it’s appropriate,
If you were to provide your own nav
sample code in this chapter’s com
Because of data binding, changes to
What is does have, however, is this
What you then do inside the element
• The groups themselves are all s
and the current viewable area. Thou
Styling Following the precedent of
Technically speaking, the layout pr
or you can set layout.groupInfo fro
Using the first item’s dimension
You can set a breakpoint in this fu
Incremental Loading Apart from pote
The yellow bars indicate execution
If it’s not provided (as when the
During initialization (outside the
Chapter 6 Layout Compared to other
that appear when needed through app
Within the body of content, then, W
} -ms-grid-columns: 120px 2fr 80px
-ms-scroll-snap-x Shorthand to comb
WinRT: filled -ms-view-state: fille
Handling View States As I just ment
var mql = window.matchMedia("(-ms-v
individual items in snapped view. B
FIGURE 6-5 Options for display size
If your developer sensibilities obj
Content goes here This is really
Such a layout is most easily achiev
Because the specs themselves are st
/* In CSS */ #divMain { width: 100%
CSS styles that are supported for W
Within the activated handler docume
Multicolumn Elements and Regions Tr
FIGURE 6-9 CSS region chains to flo
Chapter 7 Commanding UI For consume
• Commands that can’t be placed
which provide many specifics on pla
Tip To prevent the app bar from app
This example doesn’t provide any
var appbar = document.getElementByI
• afterhide occurs immediately af
This button’s click handler uses
In the extraClass properties we’v
To provide graphics of your own, do
It should come as no surprise by
Flyouts and Menus Going back to our
are optional with show. (Note also
function confirmOrder() { bought =
The point of this last example is t
Also, go into css/header-menu.c
In the contextmenu handler menu.sho
Scenario 3 is identical to Scenario
The app bar now appears as follows,
This message will appear if the use
Chapter 8 State, Settings, Files, a
while our permanent home was being
• Account and profile configurati
By the way, you might have some rea
var localSettings = Windows.Storage
It is also possible to migrate app
Tip There are some file extensions
Sidebar: Closing Streams vs. Closin
Using App Data APIs for State Manag
efore setting up new defaults. As m
Roaming State The automatic roaming
good idea to not be too aggressive
Each app-supplied command can do on
There are two ways to implement thi
function helpCommandInvoked(e) { va
Programmatically Invoking Settings
Sidebar: Changes to Permissions A c
Think about this for a moment (as I
eturns an appropriate StorageFile o
function pickSinglePhoto() { // Ver
When picking multiple files, the re
indicate a new filename in which to
scenario oriented on the music libr
A QueryOptions is generally created
The setPropertyPrefetch method goes
What We’ve Just Learned • State
Chapter 9 Input and Sensors Touch i
• Second, when you need to handle
One or more fingers touch the scree
You might notice a conspicuous abse
Note that this method has no effect
• TouchCapabilities Properties ar
Tip Pointer events won’t fire if
Properties Description currentPoint
The first step to receiving gesture
• MSGestureHold occurs when MSPoi
FIGURE 9-3 A conceptual representat
FIGURE 9-4 The Input Instantiable G
obviously a specific deceleration m
• Process keydown, keyup, and key
For passwords you get a key to hide
keyboard sample. 50 Adding listener
Standard Keystrokes The last piece
FIGURE 9-9 The Input Ink sample wit
(string), and timestamp (Date) prop
Like all other WinRT APIs, however,
Here’s an example of such code fr
Chapter 10 Media To say that media
movie.controls = true; document.get
declared inline, created dynamicall
} document.getElementById("r").styl
function onImageError(source) { sou
• By copying pixel data from a vi
It’s also helpful to understand t
Video Element Extension APIs Beyond
vid.msInsertVideoEffect("GrayscaleT
elements with the same source. The
in the background. As a developer,
function soundLevelChanged() { //Ca
Playing Sequential Audio An app tha
need to bypass the audio element an
To guarantee the ordering we use Pr
Thumbnails First, StorageFile.getTh
or combination of System.GPS.Longit
} return degrees + "°" + minutes +
Most of the displayImageUI function
provides a specific BitmapEncoder i
method can be called only once and
Transcoding and Custom Image Format
Transcoding happens either from one
In Scenario 2, the sample always us
Media Capture There are times when
ecordLimitationExceeded Fired when
} captureInitSettings.videoDeviceId
} // Add the devices to deviceList
Streaming from a Server and Digital
Here’s how such apps generally wo
Next you’ll want to wire up handl
• WinRT provides a rich API for m
necessary. In this way, excessive a
The Control Panel setting can be ob
screen; the Panel animations are fo
want to chain or synchronize animat
Create addToList animation. var add
CSS Animations and Transitions As n
Animations work in an opposite mann
Keyframes, while typically defined
FIGURE 11-2 Output of Scenario 3 of
What’s more, requestAnimationFram
Still, 20% is a lot of CPU power to
Chapter 12 Contracts Recently I dis
File activation (file type associat
more specific. For instance, when a
var dataPackageTitle = document.get
The other interesting part of Scena
When sharing an image, don't forget
FIGURE 12-3 The Share content targe
• Acknowledge user actions when y
The key here is the args.detail.sha
target app. If you’re using image
FIGURE 12-7 Controls to create a qu
The question is how to wire up comm
The Search contract that makes this
FIGURE 12-11 The Search declaration
} } })); In the search activation p
} }); Windows.ApplicationModel.Sear
The request object also has a getDe
Type to Search The final feature of
egistered for that type, rather tha
At the very bottom of this UI you c
ecord a new sound. In such cases, h
Activation of a File Picker Provide
Windows.ApplicationModel.Activation
A final note is that a file picker
}; // Create a file to provide back
The next step for the provider is t
FIGURE 12-18 The provider sample’
FIGURE 12-21 The provider sample’
• If the UI status is visible, sw
Just as the file picker contract al
Using the Contact Picker Contacts a
} } }); Contact Picker Providers On
As you can see, the homeEmail field
Chapter 13 Tiles, Notifications, th
FIGURE 13-1 The typical default Sta
Selecting an item on the Start scre
In many ways, live tiles might redu
toss up lots of superfluous toast,
Yet Windows doesn’t want to force
The third way an app can issue upda
Providing both square and wide stat
• arguments A string that’s pas
function activated(eventObject) { i
16 or fewer characters that is used
Third, if you supply an image that
arrive on a Windows 8 machine will
The Notifications Extensions Librar
The other bits of the manifest that
In such cases it would be better to
Windows.UI.Notifications.BadgeUpdat
you’d use start time), or the pha
Tip The tile and badge updaters are
eturned from page requests, as we
through the Web platform installer.
Toast Notifications So far in this
FIGURE 13-16 Issuing text toasts th
supports addImageQuery for scale, l
A scheduled toast is created using
To update a tile, set a badge, or i
Your app should go through this sho
matter of sending an XmlHttpRequest
In the running app, the pushnotific
Background Tasks and Lock Screen Ap
FIGURE 13-18 The manifest editor fo
In this code, the BackgroundTaskBui
var internetCondition = new backgro
The Background task sample provides
Note Working with the lock screen i
Debugging Background Tasks By this
• Periodic updates for tiles and
Network Information and Connectivit
networkstatuschanged event that we
Note Windows Store apps written in
Programmatically, as noted before,
Although this option will not set u
hundred kilobytes—if you know fro
Finally, avoid using XHR for large
Starting a download transfer happen
There is also a variation of create
operations—it is possible to crea
); "form-data", "------------------
Basically, you would change the pol
Authentication, Credentials, and th
The result from pickAsync, as given
To clarify the relationship between
There is one subtle difference betw
Within the web authentication broke
https://www.facebook.com/dialog/oau
Single Sign On with Live Connect Be
setAccountPicturesAsync (for provid
And lastly it’s worth at least li
} var scenario1Link = document.getE
} return currentFeed.items[currentI
When data arrives, the handler rece
} // This is a helper function echo
On the client side, StreamSocket ag
And closing the socket in Scenario
In the sample, we first create a Me
} try { var size = dataWriter.measu
What We’ve Just Learned • Netwo
• Connecting with devices in the
The XInput and JavaScript controlle
function renderLoop() { var state =
FIGURE 15-3 Sample device enumerati
The Removable Storage sample, in Sc
• Communications are supported on
Advertising a Connection Making you
Tap to Connect and Tap to Activate
On a simpler note, publishing a URI
Other affected files in this app in
Sidebar: String Resources in Settin
the folder name itself doesn’t us
If you like, you can just send your
FIGURE 17-11 The Multilingual App T
Second, the Toolkit will detect if
Localization Wrap-Up Well, we’re
Let me say that again: all of this
Onboarding and Working through Reje
Connecting Your Website If you have
What We’ve Just Learned • An ap
What do you think of this book? We