WinMK Live

Aplikacje Metro w Windows 8 - podsumowanie możliwości

2012-01-22T23:57:00.000+01:00

Na początek mała ciekawostka - tak wygląda Windows 8 build 8180, mający już napis “Windows 8 Beta”, ale jeszcze betą nie będący. To ostatni build przed rozpoczęciem fazy Beta Ecrow. Podczas instalacji można zauważyć kilka zmian w stosunku do wersji z konferencji BUILD. Domyślnym kolor tła jest teraz niebiesko-szary (można oczywiście ustawić sobie inne tło). Niestety, mimo kilkukrotnych instalacji Visual Studio 11 Preview i elementów SDK dla Metro nie udało mi się póki co otrzymać instalacji Visual Studio pozwalającej na budowanie aplikacji Metro. Trudności nie dziwią zważywszy na fakt, że narzędzia dla Metro były dystrybuowane w czasach BUILD-a na specjalnej developerskiej odmianie x64 i bezwzględnie takiej wersji wymagały (choć podobno był nieoficjalny sposób by to częściowo obejść). Dobrze że zachowałem sobie obok poprzednią wersję Windows Preview z narzędziami, zresztą oficjalna beta coraz bliżej.

Ale w sumie ten post miał być nie o tym –:) Postanowiłem zebrać tu i uporządkować całą masę informacji, jakie można było otrzymać po obejrzeniu sesji z BUILD i zapoznaniu się z dokumentacją MSDN, jak i dokumentami ją uzupełniającymi –:) Aby nie stracić na czytelności i nie zakopać się w szczegółach technicznych, ograniczam się głównie to zagadnień i funkcjonalności, nie wyszczególniając jak można je realizować (czasami są alternatywne podejścia między HTML5 a .NET/C++).

Rodzaje aplikacji

Metro (x86, x64, ARM)
Desktop (x86, x64)

Windows Runtime
- nowe obiektowe API w C++ z projekcją na języki: C#, VB.NET, C++ (przyjmowanie konstrukcji i podstawowych typów, konwencji nazewniczych z danego języka/technologii)
- metadane .winmd zgodne z metadanymi .NET
- oparte na modelu COM (co nie jest w praktyce widoczne)
- własne komponenty - definiowane w .NET i C++ i wykorzystywane z poziomu wszystkich języków
- możliwość napisania projekcji na inne języki
- możliwość wywoływania wybranych funkcji z Win32 API tam, gdzie nie możemy jeszcze skorzystać z API WinRT
Technologie
- XAML + C#/VB.NET/C++
  - profil .NET przypominający Silverlight (drobne różnice w XAML, inne przestrzenie nazw, nowe funkcjonalności w kontrolkach np. podpowiadanie i spell checking w TextBox, czasami odpowiedniki dotychczasowych kontrolek - np. WebView i RichTextBlock , nowe kontrolki, domyślny wygląd Metro, brak niektórych funkcjonalności w UI - np. w bindingu, nie ma np. gradientu kołowego, przycinania obiektów, ImageBrush, zaokrąglonych rogów, efektów, własnych easing functions, grafiki 3D, czasami zmienione nieco klasy z core, problemy z INotifyPropertyChanged (2 wersje, zamiast ObservableCollection<T> używać ObservableVector<T> z przykładu), async z C#5, czasami nowe API - np. zdarzenia do pointerów zamiast myszy, dostęp do danych na dysku - odpowiedni storage, operacje na plikach tylko asynchroniczne, inny model aplikacji)
  - uproszczony C++ np. automatyczne zarządzanie pamięcią^, przypomina C#, biblioteki znane z C++ (STL, Bust itp.)
- HTML5 + JS
  - podstawy
    - standardy i technologie HTML5 (z uwagi że jest to aplikacja natywna czasami występują pewne różnice w zachowaniu, hostuje ją dedykowany proces, który oferuje nadzbiór możliwości oferowanych przez Internet Explorer 10 np. dostęp do WinRT, czasami też trzeba implementować w HTML-u w określony sposób by aplikacja chodziła wydajniej - np. mimo nawigacji fizycznie mamy model 1-stronicowy, brak możliwości hostowania innych technologii za wyjątkiem kilku kontrolek ActiveX Microsoftu)
    - WinJS (fragmenty, nawigacja, operacje asynchroniczne, predefiniowane i własne kontrolki, binding, szablony w listach, stylowanie kontrolek - parts, dostęp do funkcjonalności systemowych)
  - czasami niektóre mniej podstawowe funkcjonalności mają inaczej rozwiązane API niż w przypadku .NET
- DirectX C++ (gry)
Capabilities
Manifest & package
Splash screen
Narzędzia
- Microsoft Visual Studio 11 Express for Windows Developer Preview
- Symulator (całkiem zaawansowany, wiele rozdzielczości, emulacja gestów multi-touch)
- Blend 5 Preview
Ekran
- wykrywanie orientacji: Landscape, Portrait
- wykrywanie layoutu: Snapped, Filled, FullScreen
- wykrywanie rozdzielczości: urządzenia od dużych ekranów HD do slatów - obsługa różnych predefiniowanych rozdzielczości, pixel density
Wejście
- Dotyk/mysz/pointer
- Gesty i manipulacje
- Ink (pointer API, zbieranie, rozpoznawanie pisma odręcznego)
- Klawiatura
- Funkcjonalności
  - przełączanie między aplikacjami (ruch od lewej krawędzi)
  - snapping
  - charms (ruch od prawej krawędzi / Window+C)
  - aplikacji/wyświetlanie appbar (ruch od dolnej lub górnej krawędzi)
  - zaznaczanie elementu w kolekcji (krótki ruch w dół, długi przeciąga)
  - semantic zoom (pinch & strength powoduje zmianę wizualnego prezentowania pogrupowanej kolekcji na bardziej odpowiedni dla danej skali)
Nowe kontrolki
- ApplicationBar
- CarouselPanel
- CaptureElement
- Flyout
- FlipView
- GridView (grupowanie danych)
- JumpViewer / SemanticZoom
- ListView (wirtualizacja danych – 2 sposoby)
- MediaPlayer
- PopupMenu
- ProgressRing
- Rating
- RichTextBlock
- SettingsPane
- ToggleSwitch
- VariableSizedWrapGrid
- WebView i WebViewBrush
- WrapGrid
Animacje

Predefiniowane JS

Nawigacja (enterPage, transitionPage)
Content (transitionContent, reveal / hide, reposition, crossFade, createPeekAnimation dla tile, updateBadge)
Uzupełnienia (showPopup / hidePopup, showEdgeUI / hideEdgeUI, showPanel / hidePanel, fadeIn / fadeOut)
Kolekcje (createAddToListAnimation / createDeleteFromListAnimation, createAddToSearchListAnimation / createDeleteFromSearchListAnimation, dragSourceBegin / dragSourceEnd, dragBetweenEnter / dragBetweenLeave)
Wybieranie (pointerUp / pointerDown, crossSlideReveal, crossSlideSelect / crossSlideDeselect)

Predefiniowane .NET/C++

Transition animations: AddDeleteThemeTransition, ContentThemeTransition, EntranceThemeTransition, ReorderThemeTransition
Theme animations: CrossSlideBackThemeAnimation, CrossSlideHintThemeAnimation, DropTargetItemThemeAnimation, FadeInThemeAnimation, FadeOutThemeAnimation, PopInThemeAnimation, PopOutThemeAnimation, RepositionThemeAnimation, SelectDownThemeAnimation, SelectUpThemeAnimation, SplitCloseThemeAnimation, TapDownThemeAnimation, TapUpThemeAnimation, SplitOpenThemeAnimation

Własne animacje (animacje niewykonywane w osobnym wątku trzeba jawnie aktywować)

Izolacja aplikacji
Cykl życia aplikacji

stany: uruchomiona, uśpiona, zakończona
aplikacja może być uruchamiana przy bardzo dużej liczbie scenariuszy

kamera
contact picker
urządzenie (AutoPlay)
plik danego rodzaju
file picker
typowe uruchamianie (z okna startowego)
zadanie drukowania
protokół danego rodzaju
wyszukiwanie
cel dla operacji wysyłania
cel dla operacji współdzielenia

Taski w tle

predefiniowane usługi
- audio w tle
- transfer plików w tle (możliwość mierzenia kosztów i wznawiania; protokoły - HTTP, HTTPS, FTP; file schema; wsparcie dla autentykacji i własnych nagłówków HTTP)
- notyfikacje push
własne

do krótkich zadań (najczęściej na potrzeby komunikacji)
aplikacja musi być na lock screen
uruchamiane są w odpowiedzi na predefiniowane triggery (InternetAvailable, InternetNotAvailable, LockScreenApplicationAdded, LockScreenApplicationRemoved, NetworkNotificationChannelReset, NetworkStateChange, ServicingComplete, SessionConnected, SessionDisconnected, SessionStart, SmsReceived, TimeTrigger, TimeZoneChange, UserAway, UserPresent) i przy predefiniowanych warunkach (InternetAvailable, InternetNotAvailable, SessionConnected, SessionDisconnected, UserNotPresent, UserPresent)
uruchamianie w dedykowanym, oddzielnym procesie lub w procesie aplikacji
wszystkim taskom danej aplikacji są przydzielane zasoby procesora na 2s z 15 minut, nie liczy się tu czas oczekiwania
taskiem może być dll-ka dołączona do projektu aplikacji lub plik z JS!

Charms
- Search (query suggestions, result suggestions, customizacja)
- Share (dane: tekst, URI, HTML, sformatowany tekst, bitmapy, pliki, własne formaty, asynchroniczność, możliwość prezentowania postępów, wysyłanie do aplikacji lub urządzeń, możliwa realizacja asynchroniczna i z delegatem, po udanym przekazywaniu możliwość zwrócenia quicklinka)
- Devices
  - PlayTo - wysyłanie obrazu i dźwięku m.in do TV, głośników
  - drukowanie
  - wysyłanie do urządzenia z Windows 8 w pobliżu
  - …
- Settings (możliwość zdefiniowania wyglądu zupełnie po swojemu, dodania animacji)
Kontrakty
- AutoPlay Device
- AutoPlay Content
- Background tasks
- Camera settings
- Certificates
- Contact picker
- File picker
- File type associations
- Game Explorer
- Print Task Settings
- Protocol
- Search
- Send target
- Share target
- User tile provider
Dane aplikacji
- Dostęp do systemu plików
  - pliki: aplikacji, lokalne (obrazki, muzyka, video, dokumenty), na urządzeniach przenośnych i w sieci, w Internecie, udostępniane przez inne aplikacje
  - nowe API dla plików (typowe operacje w postaci asynchronicznej; dostęp do metadanych i miniatur; typy danych: URI, strumień, blob, plik – łatwa konwersja między nimi; ListView datasource adapter - prezentacja metadanych, automatyczne wsparcie dla wirtualizacji, automatyczne ładowanie miniatur, automatyczne przechwytywanie notyfikacji)
  - File Picker
- Foldery
  - Lokalne
  - Roaming
  - Temp
- Dane sesji
Kafelki (square/wide, badges, kolejkowanie notyfikacji, secondary tiles)
Notyfikacje (tile, badge i toast - krótkie i długie z dźwiękiem; lokalne, planowane i push)
Lokalizacja geograficzna

standardowo na podstawie Wi-Fi lub adresu IP, możliwość zwiększenia precyzji dzięki GPS
ustawienia administratora, użytkownika i aplikacji
standard HTML5/Windows API

Sensory
- akcelerometr
- żyroskop
- inklinometr
- kompas
- natężenie światła
- orientacji (złożenie wyników z kilku fizycznych sensorów)
- orientacji prostej (orientacja ekranu)
- GPS (przy lokalizacji geograficznej)
- NFC (przy proximity)
- …
Urządzenia
- enumeracja urządzeń
- monitorowanie dodania nowego urządzenia, usunięcia, zmiany
- enumeracja kontenerów
- ustalanie miejsca urządzenia (np. czy kamera jest z przodu czy z tyłu)
- wyświetlanie ikony urządzenia
- wbudowane funkcjonalności (np. drukowanie, PlayTo, wysyłanie, komunikacja; możliwości rozszerzeń dla niektórych)
- kamera internetowa
- urządzenia przenośne (zapisywanie i odczytywanie plików)
- SMS (wysyłanie i odbieranie)
Drukowanie (z obsługą podglądu i paginacji, możliwość konfiguracji liczby i kolejności opcji na oknie dialogowym)
Tap & Go / Proximity (wymiana informacji pomiędzy 2 urządzeniami przez ich dotyk lub zbliżenie)

przykłady: wymiana linków i obrazków, gra z wieloma użytkownikami, subskrypcja i publikowanie wiadomości
zetknięcie 2 urządzeń - szybka wymiana danych lub zainicjalizowanie dłuższej komunikacji opartej na TCP/IP, Wifi-Direct lub Bluetooth
wysyłanie i odbieranie prostych wiadomości
peer-to-peer: połączenie się z tą samą aplikacją na innym komputerze (zostaje uruchomiona jeśli nie stało się wcześniej, gdy nie jest zainstalowana następuje automatyczne przekierowanie na odpowiednie miejsce w Windows Store)
wykorzystanie kontraktu Share do przesyłania plików

Multimedia

Dostęp do metadanych plików multimedialnych
Automatyczne rozpoznawanie urządzeń Bluetooth audio
Odtwarzanie (w tym playlisty, wybór ścieżki audio, Stereo3D video, efekty audio i video, wybór urządzenia wyjścia audio - np. przez Bluetooth, zabezpieczenia cyfrowe, wsparcie dla czasu rzeczywistego na potrzeby komunikacji i gier, tryby zoom i horyzontalny mirror dla video)
Audio w tle (hierarchie odtwarzania)
Przechwytywanie (kamera i mikrofon, zapis do obrazka, nagrywanie audio i video z możliwością ustawień niektórych parametrów jak np. jasność, kontrast, obrót, efekt stabilizacji obrazu)
Konwertowanie (konwertowanie plików audio i video do innego formatu i innej rozdzielczości, przycinanie, wprowadzanie trwałego efektu)
Strumieniowanie

PlayTo (nadawca, odbiorca: telewizory, głośniki - WD Live Hub (firmware: 2.07.17) i Onkyo AV Receivers (modele certyfikowane dla Windows 7), Media Player (od Windows 7), aplikacja Metro)
obrazu z kamery w sieć (customowy sink do realizacji video chata)

Dostęp do serwerów multimedialnych
Planowane: Smooth Streaming SDK, PlayReady
Własne rozszerzenia w C++/COM (własne formaty, kodeki, zabezpieczenia, efekty - przy odtwarzaniu i przechwytywaniu; dostępne tylko wraz z daną aplikacją)

AutoPlay

WPD\ImageSource
CameraMemoryOnArrival
WPD\AudioSource
WPD\VideoSource
StorageOnArrival
ShowPicturesOnArrival
PlayMusicFilesOnArrival
PlayVideoFilesOnArrival
MixedContentOnArrival
PlayDVDMovieOnArrival, PlayBluRayOnArrival, PlayVideoCDMovieOnArrival, PlaySuperVideoCDMovieOnArrival
PlayCDAudioOnArrival, PlayDVDAudioOnArrival
PlayEnhancedCDOnArrival, PlayEnhancedDVDOnArrival
HandleCDBurningOnArrival, HandleDVDBurningOnArrival, HandleBDBurningOnArrival
UnknownContentOnArrival

Odpalanie domyślnej aplikacji dla danego rodzaju pliku lub protokołu
Komunikacja
- Http
  - HttpClient i HttpWebRequest
  - Syndykacja RSS i AtomPub
  - web serwisy SOAP (WCF)
- sokety
  - StreamSocket (klient, TCP)
  - StreamSocketListener (serwer, TCP)
  - DatagramSocket (peer, UDP)
  - StreamWebSocket (klient, websocket typu TCP)
  - MessageWebSocket (klient, websocket typu UDP)
  - ProximityStreamSocket (peer, TCP lub Bluetooth)
  - SSL
- monitorowanie statusu i kosztów połączenia
- WebAuth Broker
- OAuth
Roaming (różne ustawienia)
- ustawienia i pliki (podobnie jak w lokalnym storage, synchronizację można wykorzystać np. do kontynuowania rozpoczętego zadania na innej maszynie)
Lokalizacja (nowe podejście, lokalizacja elementów manifestu analogiczna do innych miejsc)
Aplikacje Metro dla urządzeń (automatycznie się pobierają z Marketplace lub z lokalnego nośnika i instalują po zainstalowaniu danego urządzenia w systemie)
- kamera internetowa (rozszerzenia: efekty obrazu, ustawienia specyficzne dla danego urządzenia)
- drukarka (rozszerzenia: ustawienia, notyfikacje; wymagane sterowniki V4)
- urządzenie przenośne wspierające WPD API / MB SIM (rozszerzenia)
- specjalizowane (przenośne, sieciowe, pamięci masowej, I/O, inne np. kamera, smartphone, czytnik kart kredytowych, czytnik eBooków)
Aplikacje Metro dla połączeń internetowych w urządzeniach mobilnych (wybór planu, zarządzanie kontem, pomoc, notyfikacje)
Integracja z wyszukiwarką Bing (rejestrowanie aplikacji, tak by pojawiała się w wynikach wyszukiwania, w których znajduje się dana strona Web, Bing uruchamia aplikację z wyników poszukiwań)
Live Services SDK
- Single Sign On (po zalogowaniu do Windows)
- Łatwa integracja z Skydrive, Hotmail, Messenger
Kryptografia (m.in obsługa SSL, obsługa certyfikatów - zapis i odczyt w obrębie aplikacji, przy odpowiednim capability możliwy odczyt na poziomie systemu, także tych z urządzeń przenośnych, co pozwala realizować biznesowe aplikacje np. z bankowości, możliwość instalacji przez manifest lub API, możliwość rozszerzeń)
Accessability (UI Automation/Web-ARIA)
Unit testy (aplikacje XAML)
Dystrybucja
- Sposoby
  - Windows Store (trial apps & in-app purchase, do 5 komputerów)
  - Enterprise
- Windows App Certification Kit (testowanie przed wydaniem)
- Extensions SDKs
  - Framework extension SDKs (przykład: C runtime SDK, w aplikacji zawarta zależność w manifeście, przy uruchomieniu aplikacji framework jest dociągany z Windows Store)
  - Non-framework extension SDKs (nasze biblioteki lub jakiegoś dostawcy, dystrybuowane razem z aplikacją, możliwość instalacji jako rozszerzenie VSIX)

Uważam że najbardziej ciekawe są: idea WinRT, funkcjonalności w UI, taski w tle, multimedia, kontrakty, proximity, roaming, obsługa urządzeń, aplikacje dla urządzeń i dla operatorów internetowych.

Notatki o Windows 8 - odc. 25

2012-01-21T17:26:00.000+01:00

Aplikacje Metro: dodatkowe informacje o sensorach, dodatkowe informacje nt. funkcjonalności PlayTo (parowanie urządzeń, rodzaje odbiorców, tips & tricks), dostęp do zawartości serwerów multimedialnych, aplikacja Metro jako odbiorca PlayTo (godne uwagi - nie ma tego jeszcze w dokumentacji MSDN), testowanie aplikacji za pomocą Windows App Certification Kit, Windows Store (nowe, dość szczegółowe informacje w dokumentacji MSDN po zaprezentowaniu sklepu opinii publicznej).

Overview of motion and device orientation for Windows Developer Preview

Accelerometer

X = 0, Y = 0, Z = -1

Inclinometr

Play To and media sharing for Metro style apps

Media sharing in the next version of Windows can be summarized by the following three scenarios.

Streaming media from apps to Play To Receivers - new developer API makes it easy for developers to enable Play To media streaming from apps to devices like TVs and Audio Receivers.
Consuming media from Media Servers - new developer API makes it easy for developers to build rich media experiences for media stored on Media Servers on a user’s home network.
Adding Play To Receiver functionality to apps - new developer API makes it possible for apps to embed Play To Receiver functionality and become targets for the media streaming experiences.

Play To media streaming

Play To supports streaming of local media files, files from DLNA media servers and also streaming media from the internet.

On private networks Windows automatically discovers and pairs certified Play To devices when users select Enable sharing and connect to devices while provisioning the network.

On a public network, and when users do not want sharing enabled by default, devices will need to be manually paired using the Control Panel.

Companion Experiences

The Play To API provides a number of events and interfaces that make it possible for developers to create powerful companion experiences – like media playlists, photo slideshows, and contextual information on the PC while media is playing on the remote device.

Play To Receivers for Developer Preview

Play To for Metro style apps is designed to work with only Windows Certified Play To Receivers.

Only the below list of Play To receivers are supported in the Developer Preview. For scenario testing/validation from apps the easiest solution is to use Windows Media Player on another PC on the same Private Network. Other available devices are:

WD Live Hub (firmware version: 2.07.17)
Onkyo AV Receivers (Windows 7 Certified models)
Windows Media Player (on Windows 7 and the Windows Developer Preview) - both PCs need to be on the same private network, and the player needs to be open to stream to it (Stream –> Allow remote control of my Player)
Metro style apps with Play To Receiver functionality

Tips & tricks

The ‘src’ attribute of an element can be changed after it has been connected to a Play To Receiver to stream media playlists and image slideshows.

setTimeout(function(){

document.getElementById("player").src = "image2.jpg";

}, 10000);

</script>

Application can generate and stream images on the fly by drawing on the <canvas> element and taking a snapshot of its content using its msToBlob() method.

var blob = document.getElementById("renderer").msToBlob();

document.getElementById("player").src = URL.createObjectURL(blob);

</script>

Applications can easily query the friendly name of the device that the media is being streamed to.

var ptm = Windows.Media.PlayTo.PlayToManager.getForCurrentView();

ptm.addEventListener("sourceselected", function(e) {

log(e.friendlyName);

});

</script>

To improve the application memory footprint the next version of Windows introduces non-reusable blob URLs. You can enable this feature by passing false as the second parameter of URL. createObjectURL(). This is currently not compatible with Play To.

Accessing media servers

You may want to access media files from other DLNA media servers connected to the home network. In order to do so, an application needs to integrate the new file picker APIs. These APIs are used to trigger the Metro style UI that gives users the option to find files locally, in removable storage, or in media servers connected to the network.

You can apply a filter to the FileOpenPicker() function to access specific paths in the hierarchy. For example, the path that shows media servers is either Files/Desktop/Computer/Media Servers or Files/Computer/Media Servers.

Any DLNA media server exposes content using its own hierarchy of containers. Each container can include other containers or media items. The first layer typically includes containers called Music, Videos, and Pictures. The second layer under Music sometimes includes a container called All Music. The file picker integrates the Windows hierarchy and the media server hierarchy into a single tree. For example, a user can navigate from the root to All Music using:

Files -> Computer -> Media Servers -> MyServerDevice -> Music -> All Music

You can use the URL.createObjectURL() function to obtain the URL for the selected file object. The URL is then inserted programmatically into a video element. The content referenced by the video element can be played by default in the App, or it can be pushed to any Play To receiver in the network.

Making apps Play To Receivers

The new Play To Receiver API in the next version of Windows makes it possible for any Metro style app to become a Play To target for audio, video, and images.

The following steps provide a walkthrough for getting started with the Play To Receiver developer sample. You can download the sample from the samples gallery.

Windows Media Player (Stream –> Turn on media streaming…)

Click Start Receiver in the sample
On Private networks, the receiver will automatically be paired with the machine within a few minutes; on public networks, the device will need to be manually added
Click Play in the Video
Swipe in the Device charm, and select the Receiver
Watch the video stream to the Play To Receiver media element!

Using the Windows App Certification Kit

Starting with Windows Developer Preview, we are introducing the Windows ACK to replace the WSLK.

Windows ACK will be available as part of the Windows Software Development Kit for Metro style Apps. The toolkit is already pre-deployed on the Windows Developer Preview image, and at present it cannot be obtained through any other mechanism.

Validating apps

After the validation process concludes, Windows ACK will generate a report.

Windows Store

With successful apps on Windows you'll make more money than the industry standard, earning 80% of every customer dollar after an app makes more than 25,000 USD in sales. For the first 25,000 USD of an app's sales, you get the industry-standard 70%.

The price tier sets the price of your app. You can offer your app for free or, when the Windows Store supports sales, pick a price tier for it. Price tiers will be available from 1.49 USD on up, in increments of 0.50 USD to 4.99 USD, with higher price tiers also available.

The cost to register for a Windows Store developer account in the United States is 49 USD for an individual and 99 USD for a company.

Poland: 140 PLN / 280 PLN paid to bank or PayPal

Apps can also show ads to your customers. You can show ads from apps that also sell in-app purchases and from apps that have a trial period.

Third-party transactions

Apps can also make money in ways other than those the Windows Store provides. You can use a third-party transaction provider or benefit from ties to other lines of business as long as the transactions comply with the App Developer Agreement. For example, if you have a transaction platform that integrates into a CRM system, you can use that in your app to keep track of your subscribers.

Windows Store markets

On or before the date on which Windows 8 Release Candidate is released, Microsoft may (but is not obligated to) remove any or all apps and content from the pre-release Windows Store, as well as from any devices onto which they may previously have been downloaded or installed.

Roaming is a Windows 8 feature that enables users to use your app on up to 5 Windows 8 enabled devices at any one time, unless you identify your app as eligible for distribution by only named OEMs, or on only an ARM or X86 processor. Only the most recently distributed version of your app will be roamed to consumers.

All apps submitted through the pre-release version of the Windows Store must be for no charge. Microsoft will not process any payments related to apps during the beta period, including payments for in-app purchases.

Some certificate requirements:

Each app must display only one tile after it is installed
Your app must not display only ads
Your app must not use tiles or notifications for ads
Your app must do more than open a website or mimic the behavior of a website. Your app must provide a reasonable snap state; it shouldn't be cut off when snapped. Your app must also support touch, keyboard, and mouse input.
Ads must not execute program code that did not come from the ad provider
Your app must provide the same user experience on all processor types
Your app must fully support touch interactions. Your customers must be able to access all of your app's functionality using only touch interactions and gestures.
Your app must protect customers from unintentional large data transfers over metered networks
You must provide technical support info for your app

Enterprise deployment. An option for developers who create apps for use within an organization is enterprise deployment. Enterprise deployment enables your apps to be distributed to users within the enterprise without going through the Windows Store.

Notatki o Windows 8 - odc. 24

2012-01-20T23:59:00.000+01:00

Aplikacje Metro: migracja z aplikacji web i z Windows Phone 7, tworzenie komponentów Windows Runtime. Interesujące informacje z Windows Developer Preview Windows 8 guide na temat systemu operacyjnego. Szczególnie polecam temat tasków w tle w aplikacjach Metro (z dodatkowego dokumentu Introduction to background tasks. Guidelines for developers, tych bardzo istotnych informacji nie ma jeszcze w dokumentacji MSDN).

Migrating a web app

The process that hosts and executes a Metro style app using JavaScript is called WWAHost.exe. This process provides a superset of functionality greater than that provided by the Microsoft Internet Explorer browser.

Libraries:

The Windows Library for JavaScript -- A toolkit of JavaScript libraries that support improved event handling and DOM query behaviors, enable new control types, and provide developer-friendly patterns for other common JavaScript behaviors.
Trident 6.0 -- An HTML- and CSS-based model for the layout and rendering of visual components that implements Canvas for the real-time drawing and manipulation of bitmap graphics, and Scalable Vector Graphics (SVG) support for vector graphics. (Trident 6.0 is the set of libraries used by Internet Explorer 10 for the display of content, and can be used to support additional graphics and rendering behaviors.)
The Windows Runtime -- Common APIs available to JavaScript by using the Windows Runtime infrastructure.

The WWAHost.exe provides an Internet Explorer-based rendering platform.

WWAHost.exe cannot host Adobe Flash Player, Microsoft Silverlight, Java objects most ActiveX controls and other embedded components. The following ActiveX controls are supported:

{88d96a05-f192-11d4-a65f-0040963251e5} XML DOM Document 6.0
{88d96a06-f192-11d4-a65f-0040963251e5} Free Threaded XML DOM Document 6.0
{88d96a07-f192-11d4-a65f-0040963251e5} XML Schema Cache 6.0
{88d96a08-f192-11d4-a65f-0040963251e5} XSL Template 6.0
{EE09B103-97E0-11CF-978F-00A02463E06F} Scripting.Dictionary
{B4644768-6186-4010-89AC-D6FD32CCD3E6} Testing Hook: Test Max Service
{FFC4E997-D97B-45DF-AD22-44C4B2DEDD2B} Testing Hook: Test WTT Logger
{186DD02C-2DEC-41B5-A7D4-B59056FADE51} PortableDeviceAutomation.Factory

Migrating a Windows Phone 7 app

Resolutions, input (WP7 touch oriented), phone-specific functionality in WP7, XNA to DirectX C++.

Note that the following Silverlight XAML namespaces do not have a direct analog in the Windows Runtime:

System.Windows.Automation.Text
System.Windows.Ink
System.Windows.Media.Effects
System.Windows.Messaging

Differences between Silverlight and Metro style apps using XAML:

Tiles have similar behaviors to Live Tiles in Windows Phone 7, although there are some differences.
Notifications are an extension of the push notification model in Windows Phone 7.

Creating Windows Runtime Components

With the .NET Framework 4.5 Developer Preview, you can use managed code to create your own Windows Runtime types, packaged in a Windows Runtime Component. Visual Studio makes it easy to add a C# or Visual Basic class library to your app, and to create Windows Runtime types that you can call from JavaScript. Internally, your Windows Runtime types can use any .NET Framework functionality that's allowed in a Metro style app. Externally, the members of your type can expose only Windows Runtime types for their parameters and return values. When you build your solution, Visual Studio builds your .NET Framework class library project and then executes a build step that creates a Windows Metadata (WinMD) file. This is your Windows Runtime Component, which Visual Studio includes in your app.

Visual Studio first compiles the class library, and then executes an MSBUILD task that runs the WinMdExp.exe utility to create the WinMD file, turning your class library into a Windows Runtime Component. The WinMD file contains both the managed code and the WinMD definitions that are used by JavaScript and the Windows Runtime. WinMdExp.exe generates build errors when you write code that's invalid in WinMD. Visual Studio adds your component to the package file (.appx) for your Metro style app, and generates the appropriate manifest.

The rules for managed WinMD and JavaScript

The .NET Framework contains many types that are not part of the Windows Runtime. You can use these types in the implementation of your Windows Runtime types, but they cannot be part of the public API surface. The following list describes the restrictions that are required by the Windows Runtime, and an additional restriction required by JavaScript.

The fields, parameters, and return values of all the public types and members in your component must be Windows Runtime types. In addition to types that are provided by the Windows Runtime itself, this includes the Windows Runtime types that you create. It also includes a number of .NET Framework types.
Classes and interfaces can contain methods, properties, and events. You can declare delegates for your events, or use the EventHandler<T> delegate. A class cannot:
- Be generic.
- Implement an interface that is not a Windows Runtime interface. (You can create your own Windows Runtime interfaces and implement them.)
- Override methods of Object other than ToString.
- Declare protected constructors.
All public types must have a root namespace that matches the assembly name, and the assembly name must not begin with "Windows".
Public structures can't have any members other than public fields, and those fields must be value types or strings.
To be usable from JavaScript, your classes must follow one more rule: You must declare them as sealed (NotInheritable in Visual Basic). This restriction does not apply to other consumers of WinMD libraries.

The following are known issues with managed Windows Runtime Components in Windows Developer Preview:

Each class in your component must have at least one instance member. Otherwise, the WinMdExp.exe utility can't create a class interface for it, and generates an error message to that effect.
You can't add events to the types in your component. If a class contains an event, attempting to instantiate the class from JavaScript results in "Unknown runtime error."
Some of the types that the .NET Framework appears to substitute for Windows Runtime types currently cannot be used as parameter types or return types of members in a component. Examples of these types include DateTimeOffset, TimeSpan, and Size. At run time, JavaScript reports a failure to load the type from the current assembly the first time the type is accessed. The corresponding Windows Runtime types cannot be used.
Visual Studio 11 Express for Windows Developer Preview fails to add classes to the app manifest if they don't have default constructors. This causes a "Class not registered" error at run time, when JavaScript code tries to instantiate the class. The workaround is to add a default constructor. When you encounter this error, simply adding a default constructor to the class doesn't fix the problem. Stop the debugger and then delete the AppXManifest.xml file from the Debug folder, forcing Visual Studio to regenerate the file and add the class. Alternatively, you can manually add the class to the extensions section of the manifest.
In Visual Studio 11 Express for Windows Developer Preview, the debugger doesn't show the correct members for some of the types that the .NET Framework appears to substitute for Windows Runtime types.
In Visual Studio 11 Express for Windows Developer Preview, the debugger is sometimes unable to obtain values for local variables. For example, in event handlers the parameters are frequently unavailable.

In Visual Studio 11 Express for Windows Developer Preview, you can't debug JavaScript and managed code at the same time.

In the .NET Framework, primitive types like the Int32 structure have many useful properties and methods, such as the Int32.TryParse method. By contrast, primitive types and structures in the Windows Runtime only have fields. When you pass these types to managed code, they appear to be .NET Framework types, and you can use the properties and methods of the .NET Framework types as you normally would.

You can tell when a Windows Runtime type appears as a .NET Framework type, because the IntelliSense in Visual Studio hides the Windows Runtime type when you're writing managed code, and presents the equivalent .NET Framework type.

Windows Developer Preview Windows 8 guide

Windows 8 has two touch keyboards for ultimate mobility and flexibility. An improved, full-sized touch
keyboard with larger buttons and a unique thumb keyboard make it easy to use your computer on the
go. Whether you’re walking around or sitting down, it’s more comfortable and natural to type using your
thumbs when the keyboard is split.

When you sign in with your connected Microsoft account to another PC running Windows 8, your Metro
style apps and settings go with you, so it’s just like you’re using your own PC. You’ll also be signed in to all
of the websites you were signed in to. Your connected account is like a portable, personal PC that appears
on any Windows 8-based PC you’re using.

Metro style apps run and stay up to date even when the PC is on standby. When you’re connected to the
Internet, you’ll receive information updates, email, VoIP calls, instant messages, and be able to stream
music or other content in the background. When Windows comes out of standby, your apps don’t need
time to catch up.

You can install your purchased apps on up to five Windows 8 PCs.

On x86 and x64 PCs, Windows 8 supports Windows 7 desktop applications and devices so you don’t have to
compromise or give up what you’re used to. On these PCs, your existing Windows 7-based applications just work.

Push-button reset

Windows 8 comes with a number of options to restore your PC to its original state. You can do a basic reset, which gives you an easy option to restart fresh while retaining all of your documents, accounts, personal settings, and even the apps you’ve downloaded from the Windows Store.

Windows 8 also provides some new, advanced options. You can do a complete reset, which restores the PC to
the state it was in when originally purchased. And you can also create a reset disk, which is great for power
users who have invested time to personalize and configure their PC. Restore from USB Key restores your PC
from a thumb drive, saving space and giving you a convenient backup tool.

Windows Update

If you turn on Windows Update during setup and your computer needs an update,
Windows can install it when you’re not using your computer or at a time you’ve specified. When an
update requires a reboot, there’s a grace period, allowing you to pick a time that’s convenient for you. As
a result, you see far fewer prompts about maintenance, updates, or reboots.

Windows Runtime

WinRT features are represented by the Application Binary Interface (ABI), which makes Windows APIs
accessible from other programming languages. The ABI is exposed in metadata assemblies (.winmd files),
allowing static languages (like C#) and dynamic languages (like JavaScript) to understand the structure of
the WinRT API.

Developing for IE 10

With the release of IE10, developers get even more support for HTML5, enabling them to create rich
visual effects and animations with hardware accelerated CSS transitions, animations, 3D transformations,
along with CSS3 text shadow, gradients, and SVG filter effects. Building increasingly sophisticated page
layouts is possible with support for CSS3 grid, flexible box layout, multi-column, figures, CSS3 regions, and
hyphenation, as well as HTML5 Forms and Input Controls.
The IE10 platform also includes support for local storage including IndexedDB, Application Cache, Async
scripts, Web Workers, ES5 Strict mode support, Web Sockets, HTML5 file APIs, drag-drop, history, and
sandboxing. These features give developers an increasingly sophisticated, standards-based, programming
model that is ideal for creating modern web experiences.

System requirements

Windows 8 works great on the same hardware that powers Windows Vista and Windows 7:

1 gigahertz or faster 32-bit or processor
1 gigabyte (GB) RAM (32-bit) or 2 GB RAM (64-bit)
16 GB available hard disk space (32-bit) or 20 GB (64-bit)
DirectX 9 graphics device with WDDM 1.0 or higher driver

Of course, taking advantage of touch input requires a screen that supports multi-touch.

In addition to running on x86 and x64 devices, Windows 8 delivers even greater flexibility by running on
ARM devices. Depending on the technology you use, write your Metro style apps once and they can run on
any supported architecture.

Introduction to Background Tasks

Windows Developer Preview provides a number of features to make an app look alive with content even when the app is suspended:

Windows push notifications can be used to keep the app tile fresh and up-to-date.
Playback Manager can be used to play audio in the background.
The background transfer API can be used to download and upload files in the background.
File share contracts can be used to share data between apps.

Push notifications and the background transfer API are optimized for system performance and longer device battery life, so it’s best to use these features whenever possible. If a suspended app must run its own code to do other kinds of work, Windows Developer Preview provides apps with the ability to create background tasks.

Allowing apps to run code in the background when they are suspended is a powerful feature and is designed primarily for the real-time class of apps such as mail, VOIP, and chat apps. The background task execution environment is a restricted resource-managed environment and background tasks only receive a limited amount of CPU time. Background tasks should be used for small work items that have no interaction with the user and only provide limited service. Long running or expensive workloads in the background will deplete the user’s battery and are not an appropriate use for background tasks.

Scenarios that are appropriate for background tasks include downloading mail in the background, or showing a toast notification for an incoming VOIP call or a chat message, or reacting to a change in system condition (for example, UserAway) and updating the server with this information. Scenarios that are not appropriate for background tasks are indexing mail, transcoding photos, running SETI type workloads, or anything that requires user interaction through displaying UI or audio.

Real-time apps and the lock screen

To prevent abuse of system resources or excessive workloads that might drain the device battery, only apps that are on the lock screen are allowed to use background tasks. If an app that is not on the lock screen tries to access the time trigger or the real-time communication trigger, its background task will not be triggered.

If the user notices an app is running often and taking up too many resources in the Task Manager, the user can remove the app from the lock screen to prevent it from performing its background task activity. An app can register to be notified when it is added or removed from the lock screen by registering a background task with the LockScreenApplicationAdded or LockScreenApplicationRemoved triggers provided in the SystemTrigger class.

Terms and definitions

Background Task - a class implemented by the app to provide functionality even if the app is not in the foreground.
Background Trigger - a system-defined event that an app can associate with a background task. When the trigger is fired by the system, an app background task associated with the trigger is launched.
Background Condition - a set of zero or more conditions that need to be satisfied before the background task can run.
EntryPoint - the name of the class implementing the background task.
backgroundTaskHost.exe - a system-provided host executable to run the background task.

Background task architecture

A Metro style app registers its background tasks with the background task infrastructure by using the BackgroundTaskBuilder class. The background task is implemented as a class that implements the IBackgroundTask interface. This class name is specified in the TaskEntryPoint property of the BackgroundTaskBuilder class. The background task class is hosted in an in-proc server DLL which can be loaded in an app executable, as part of the app package, or in the system-provided backgroundTaskHost.exe.The background task can also be implemented as a JavaScript worker. The JavaScript worker is included in the app as a JavaScript file and the name of the JavaScript file is specified in the TaskEntryPoint property of the BackgroundTaskBuilder class. The JavaScript worker runs in the system-provided WWA host process similar to a web worker.

A background task must have exactly one trigger that describes the trigger event to launch the background task. The trigger is specified with the SetTrigger method of the BackgroundTaskBuilder class.

Background task trigger events

InternetAvailable
InternetNotAvailable
LockScreenApplicationAdded - an app tile is added to the lock screen.
LockScreenApplicationRemoved
NetworkNotificationChannelReset
NetworkStateChange - a network change such as a change in cost or connectivity occurs.
ServicingComplete - the system has finished updating an application.
SessionConnected
SessionDisconnected
SessionStart - the user session starts
SmsReceived
TimeTrigger
TimeZoneChange
UserAway
UserPresent

A background task can optionally have one or more conditions that must be true for the task to launch. Background conditions are used by an app to describe the set of conditions required to perform meaningful work. For example, if the background task requires the Internet but there is not currently an Internet connection, an InternetAvailable condition can be used to tell the system to wait for the Internet connection to be restored before launching the background task. Background conditions are specified with the AddCondition method of the BackgroundTaskBuilder class.

Background task conditions

InternetAvailable
InternetNotAvailable
SessionConnected
SessionDisconnected
UserNotPresent
UserPresent

Background task infrastructure

When the trigger is fired, the background task infrastructure launches the class associated with the trigger regardless of the state of the app. The activation of the background task does not involve any UI and it does not bring the Metro style app to the foreground. The triggers provided in the system are timer, system event and real-time communication.

When the trigger is fired, the system infrastructure activates the class within the app container.

Background tasks and the Metro style app lifecycle

When a background task is launched, an app can be in any of the following states: Running, Terminated or Suspended. If an app is in the Running state, it is the only app in the foreground. If an app is not running, it is in either the Suspended or Terminated state. A suspended app is resident in memory, but its work is not being scheduled by the system. A terminated app is not in memory, either because it was never launched or because it was in the Suspended state and was terminated by the system.

The background task executes in either the system-provided backgroundTaskHost.exe or the app process. The app specifies the execution host in its manifest.

If a background task executes in the system-provided backgroundTaskHost.exe, it is launched independently of the state of the app; it is not necessary for the system to change the app’s state. This option is preferable because launching the task within backgroundTaskHost.exe is faster and provides better performance than launching the background task within the app. BackgroundTaskHost.exe is launched within the same app container as the app and it terminates after the background tasks finish.

If a background task executes within the app process, the background task infrastructure might need to change the state of the app:

Running: If the app is running, it is already in the foreground and the background task is simply launched within the app.
Suspended: If the app is suspended, most of its threads are unfrozen and the background task is launched.
Terminated: If the app is terminated, it is not running at the time of the trigger so the app is activated and the background task is run. The app activation does not involve UI and it does not bring the app to the foreground.

Background task implementation concepts

All background task registrations are persistent; that is, the app doesn’t have to be running for the background task to be triggered. For example, if a background task should run 6 hours from now to download RSS feeds, the app registers the background task using TimeTrigger with the appropriate value. When the time arrives, the background task is launched regardless of whether the app is running or the machine has been restarted since the task was registered.

Condition latching behavior

When a trigger is fired, the background task infrastructure checks whether all the conditions are satisfied. If not, the infrastructure waits until all the conditions are satisfied before executing the background task. This behavior is called latching, because the background task infrastructure latches the trigger to a fired state.

If a condition changes value while a trigger is latched, the background task infrastructure re-checks to see if the conditions are satisfied for the background task. If so, it launches the task.

Background task progress reporting

The background task can use the progress handler to report progress to the app when the app is running in the foreground. The progress reported from the background task can be used to display UI or a progress bar in the foreground app.

The IBackgroundTaskInstance that is passed to the Run method is used to communicate progress to the foreground app. The interface has a Progress property which can be updated by the background task. The app must register a progress handler to receive progress updates from the background task when the app is in the foreground. The progress handler in the app does not receive the updates from the background task if the app is Suspended or Terminated.

Background task completion notification

The foreground app can also register a completion handler to be notified when the background task completes. The completion status or any exception thrown in the Run method of the background task is passed to the completion handler in the foreground app as part of the BackgroundTaskCompletedEventArgs input parameter. If the app is in the Suspended or Terminated state, it does not receive the completion notification. If the background task needs to preserve the information that it ran successfully, it must persist the information using State Manager or another means such as a file that the app can read when it comes back to the Running state.

Background task cancellation

Background tasks can be cancelled by the system in certain conditions. To receive cancellation notifications, the app’s background tasks should register a cancellation using the IBackgroundTaskInstance. When the system cancels a background task, it provides a reason in the BackgroundTaskCancellationReason parameter of the BackgroundTaskCanceledEventHandler.

If the background task does not respond to the cancellation notification and return from its background task within five (5) seconds, the app is terminated. To ensure a graceful exit and the guarantee that state is saved, apps are encouraged to register a cancellation handler and save state and exit the background task in response to a cancellation request.

Background task enumeration and re-associating handlers

When a Metro style app is launched from the Terminated state, it can enumerate all background tasks it has registered with the system using the BackgroundTaskRegistration.AllTasks method. Because the app has just been launched, it must re-associate its progress and completion handlers with the background tasks. Even if the app has previously registered those associations, they are no longer valid because the app was terminated and removed from memory. Only the progress and completion handlers must be re-associated. The background task registrations themselves are persistent.

The progress and completion handlers are event delegates or functions and are not defined in the manifest as are the class names (EntryPoint), which is why they need to be associated after the app has been launched.

If the app was resumed from the Suspended state then it does not have to re-associate its progress and completion handlers for its background tasks. They remain valid, because a suspended app remains in memory.

foreach (var task in BackgroundTaskRegistration.AllTasks)

{

task.Value.Progress += new BackgroundTaskProgressEventHandler(OnProgress);

task.Value.Completed += new BackgroundTaskCompletedEventHandler(OnCompleted);

}

var iter = Windows.ApplicationModel.Background.BackgroundTaskRegistration.allTasks.first();

var hascur = iter.hasCurrent;

while (hascur)

{

var cur = iter.current.value

cur.addEventListener("progress", onProgress);

cur.addEventListener("completed", onCompleted);

hascur = iter.moveNext();

}

App updates or servicing

Background task registrations persist across app updates. If an app is updated, its registrations continue to be valid and will be triggered. The app developer must ensure that the background task EntryPoint still exists in the updated version of the class, otherwise the background task will error out during activation. To delete a previous background task registration upon update, an app can register a background task for a ServicingComplete trigger to be notified when the app is updated, and unregister background tasks that are no longer valid.

Sample background task

private void RegisterBackgroundTasks()

{

BackgroundTaskBuilder builder = new BackgroundTaskBuilder();

builder.Name = "BackgroundTestClass"; // Friendly string name identifying the background task

builder.TaskEntryPoint = "BackgroundTaskLibrary.TestClass"; // Class name

IBackgroundTrigger trigger = new TimeTrigger(15, true);

builder.SetTrigger(trigger);

IBackgroundCondition condition = new SystemCondition(SystemConditionType.InternetAvailable);

builder.AddCondition(condition);

IBackgroundTaskRegistration task = builder.Register();

task.Progress += new BackgroundTaskProgressEventHandler(task_Progress);

task.Completed += new BackgroundTaskCompletedEventHandler(task_Completed);

}

function RegisterSampleBackgroundTaskWithCondition()

{

var builder = new Windows.ApplicationModel.Background.BackgroundTaskBuilder();

builder.name = "BackgroundTestWorker";

builder.taskEntryPoint = "BackgroundTestWorker.js";

var myTrigger = new Windows.ApplicationModel.Background.TimeTrigger(15, true);

builder.setTrigger(myTrigger);

var condition = new Windows.ApplicationModel.Background.SystemCondition(Windows.ApplicationModel.Background.SystemConditionType.internetAvailable);

builder.addCondition(condition);

var task = myTaskBuilder.register();

task.addEventListener("progress", task_Progress);

task.addEventListener("completed", task_Completed);

}

Background task class

BackgroundTaskLibrary.TestClass implements the IBackgroundTask interface that has a Run method. The Run method is where the actual background task code exists. The class implementing IBackgroundTask interface must be sealed. The Run method receives IBackgroundTaskInstance as an input parameter which contains information about the task (trigger and conditions).

namespace BackgroundTaskLibrary

{

public sealed class TestClass:IBackgroundTask

{

private int globalcount;

void IBackgroundTask.Run(IBackgroundTaskInstance taskInstance)

{

globalcount = 0;

for (int i = 0; i < 100000; ++i)

{

Interlocked.Increment(ref globalcount);

taskInstance.Progress = (uint)globalcount;

}

JavaScript

BackgroundTestWorker.js is a JavaScript file included with the app. The script in this file runs when the background task is triggered. The script can access IBackgroundTaskInstance through the WebUIApplication object as a static property. A JavaScript background task must call close after it has completed its work so that the task can be shut down.

(function()

{

"use strict";

var globalCount= 0,

backgroundTask = Windows.UI.WebUI.WebUIApplication.backgroundTask;

for (int i = 0; i < 10; i++)

{

globalCount += 10;

backgroundTask.taskInstance.progress = globalCount;

}

backgroundTask.success = true;

close();

})();

Adding a background task to a solution

To add a C# class library implementing the IBackgroundTask interface to your project, follow these steps:

Add a new Windows Metro style app class library project to the solution.
Modify the class library project properties so that it outputs a winmd instead of a DLL.
Add a reference to the newly added class library project in the main Windows Metro style app project that registers the background tasks.
Add the required manifest entries for background tasks to the Windows Metro style app project (not the class library).

To add a JavaScript background worker to your project, add a new dedicated worker file.

Background task sample manifest

Metro style apps must be manifested to use background task extension contracts. Every Metro style app has an associated manifest that is used by the app to indicate it is using the background task extension contract. An app’s manifest can contain multiple background task extensions with different class names (EntryPoint) or JavaScript files, executable, or task types within the same app.

</VisualElements>

</BackgroundTasks>

</Extension>

</Extensions>

</Application>

</Applications>

</Capabilities>

</Package>

If the manifest does not specify an executable, then the executable is the same as the app executable.

</VisualElements>

</BackgroundTasks>

</Extension>

</Extensions>

</Application>

</Applications>

</Capabilities>

</Package>

The extension must specify the triggers used by the class or JavaScript file. If the trigger type is not specified correctly, the Register operation fails.

Background task resource management

Background tasks are meant to be short-lived tasks that do not consume a lot of resources. If an app is running and the user is interacting with the app in the foreground, then no CPU quota or resource management policies are applied to the app’s background tasks.

An app on the lock screen receives a certain amount of CPU time at regular intervals for its background tasks. If the app uses all of its available CPU time, its background tasks are suspended until the app’s CPU quota is replenished at the next generation for CPU quota updates.

Each app on the lock screen receives two seconds of CPU time every 15 minutes which can be utilized by all of the background tasks of the app. At the end of 15 minutes, each app on the lock screen receives another two seconds of CPU time for use by its background tasks. Any unused CPU time in the 15-minute interval is lost and not accumulated by the app. If a background task is suspended because it has used its two seconds of CPU time, the message ‘Background work item for package “” with entry point “” was throttled by sandboxing policy’ is logged in the event viewer.

CPU usage time refers to the amount of actual CPU used by the app and not the wall clock time of the background task. For example, if the background task is waiting in its code for the remote server to respond and not actually using the CPU, then the wait time is not counted against the CPU quota because the background task is not using the CPU. CPU usage information is available in Task Manager or more sophisticated tools like xperf, which is available in the Windows Performance Tools (WPT) Kit.

The reason for using CPU usage as a unit of resource management instead of total running time or wall clock time is because that is a more fair metric for measuring actual energy usage of an app. If an app is not using the CPU and might be waiting for input, the CPU could go to a low power state, conserving battery life.

Threading model for background tasks hosted in the app

If background tasks authored in C# or C++ are hosted within the app instead of the recommended backgroundTaskHost.exe, there are some threading model complexities to keep in mind.

Decoupling the background task from the app

For non-JavaScript apps, the background tasks are hosted in an in-proc DLL which is loaded in a multi-threaded apartment (MTA) within the app. For JavaScript apps, background tasks are launched in a new single-threaded apartment (STA) within the WWA host process. The actual background task class can be STA or MTA. Because background tasks can run when an app is in a Suspended or Terminated state, they need to be decoupled from the foreground app. Loading the background task DLL in a separate apartment enforces separation of the background task from the app while allowing the background task to be controlled independently of the app.

When an app is suspended, the UI STA thread is blocked in the Windows kernel. This thread is released only when the app transitions back to a Running state in response to user interaction. When the app is in the background and a background task is triggered, all threads in the app except the UI STA thread are unfrozen and the background task is activated in an MTA thread. The UI STA thread remains blocked. If the background task tries to access an object that is owned by the blocked UI STA thread, then it will deadlock. To prevent this deadlock, the background task should not share data between the app and the background task.

Sharing state between the background task and the foreground app

Another aspect to keep in mind if the background task is loaded within the app instead of the recommended backgroundTaskHost.exe is that it cannot rely on accessing memory of the foreground app. Background tasks run regardless of the current state of the app, so background tasks cannot rely on having the app around when they run. The only reliable way for the background task to share state with the app is to use persistent storage such as State Manager or files.

Background task best practices

When using background tasks in your app, follow these best practices:

Design background tasks to be short lived.
Use backgroundTaskHost.exe as the executable for background tasks.
Describe the background task class name or JavaScript file name accurately in the manifest.
Use persistent storage to share data between the background task and the app.
Register for progress and completion handlers in the app.
Register for a background task cancellation handler in the background task class.
Register for the ServicingComplete trigger if you expect to update the app.
Ensure the C# class library output is a winmd file instead of a DLL.
Describe the triggers in the background manifest accurately.

Avoid the following:

Do not display UI other than toast notifications from a background task.
Do not rely on user interaction in background tasks.

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Notatki o Windows 8 - odc. 23

2012-01-19T21:37:00.000+01:00

Narzędzia dla aplikacji Metro: Visual Studio 11 for Windows Developer Preview (HTML5, C#, VB.NET, C++) i Expression Blend 5 for Windows Developer Preview (HTML5).

Metro style apps can use a subset of the Win32 and COM API. This subset of APIs was chosen to support key scenarios for Metro style apps that were not already covered by the Windows Runtime, HTML/CSS, or other supported languages or standards. The Windows App Certification Kit ensures that your app uses only this subset of the Win32 and COM API.

The subset of the Win32 and COM API that can be used in a Metro style app is indicated in the header files in the Windows Software Development Kit (SDK) for Metro style Apps. Look for the following statements in the header files:

#pragma region Application Family

#pragma region Desktop Family

The compiler and object browser in Microsoft Visual Studio 11 Express for Windows Developer Preview use these statements to determine whether to show or hide a Win32 or COM API element.

Tools

Visual Studio for Metro style app development

IDE for JavaScript

Project templates: Blank Application, Fixed Layout Application, Grid Application, Navigation Application, Split Application.

Item templates: HTML Fragment, Landing Page (Grid app), Collection Page (Grid app), Details Page (Grid app), Category Page (Grid app), Split Page (Grid app), Search Contract, Picker Contract, Share Contract.

Project: *.wwaproj

When you develop JavaScript solutions, you use three editors—the HTML editor, the JavaScript Code editor, and, to define styles, the CSS Editor. The JavaScript Code editor and the HTML editor provide many features that you can customize to help create your app.

IntelliSense, which provides features such as statement completion and parameter Help as you type code.
Code snippet insertion, available by right-clicking in a code file and selecting Insert Snippet.
Navigation aids such as Go To Definition (JavaScript Code editor only), Bookmarks, and Navigate To.
Outlining, word wrap, displayed line numbers, and other features.

The CSS Editor shares some of the features found in the JavaScript Code editor and the HTML editor, along with enhancements that are specific to CSS markup.

You can customize the behavior of the editors, and enable or disable features like indentation, word wrap, and statement completion (Tools –> Options –> Text Editor).

Visual Studio includes a Toolbox with HTML controls that you can use to drag-and-drop HTML controls, such as a button, into the HTML editor. However, Windows Library for JavaScript controls are not available in the Toolbox.

Metro style apps that reference managed or native back end code such as a DLL are called hybrid applications. In a hybrid app, you can make a reference to the following types of components: WinMD files, a managed or native library project that generates one or more WinMD files, a Windows Runtime SDK, or a Windows Extension SDK. A Windows Extension SDK refers to either an SDK available in the Windows Store or a third party SDK.

Windows Runtime SDKs are implicitly referenced. For other hybrid apps, you can configure the project in three ways:

Adding a second project to the solution that uses the Class Library template (C# or VB).
Referencing a native or managed WinMD file by adding a reference to the WinMD file from your JavaScript project.
Installing an SDK that contains one or more WinMD files and referencing it from your JavaScript project.

To add a reference to an external component:

In your JavaScript project, right-click the References node in Solution Explorer and click Add Reference.
In the Add Reference dialog box:
- For an Windows Extension SDK, select Extension SDKs in the Windows section. SDKs that are installed on the PC hosting Visual Studio and that contain WinMD files will appear in this tab.
- For a native or managed WinMD, browse to the WinMD file and select it.
After selecting the reference, click Add

Localization

To add a .resjson resource file to a project:

Right-click the project in Solution Explorer and click Add > New Item.
Select Resources File (.resjson) in the middle pane and click Add.
After you add the resource file, create a new folder for the localization file and localized images, and move the file there.

For example, a Canadian French localized .resjson file needs to go in \projectname\fr-CA. Images for fr-CA go in projectname\fr-CA\images.

To specify a default language for the project:

In Solution Explorer, select a project.
Click View > Property Pages.
On the Configuration tab, click General .
In Default Language, specify the correct language locale, such as en-US.

The OS environment determines the preferred language. By using a default setting for the project, you make sure that the resources in \projectname\<locale>\*.resjson are used by default when there is no better match for the OS language preferences.

IDE for C++/C#/Visual Basic

A Metro style app usually consists of a single project template for the app itself, and one or more optional Class Library or Unit Test projects grouped into a single solution. The C# and Visual Basic Class Library project can be used to create a standard .NET class library or it can also be used to create a Windows Runtime Component DLL that can be consumed by JavaScript or C++ Metro style apps. Visual C++ has a Windows Runtime Component DLL project. Visual C++ includes an additional project template that is not available in the other languages, a Metro style DirectX Application.

In Visual Basic, C# and C++ you can right-click in a code file and select “Insert Snippet” to automatically add commonly used constructs to your code.

Solution Explorer. In Visual Studio 11 for Windows Developer Preview this tool has many new features including an embedded class view and call hierarchy. You can right click on a file and drill in to the methods and variables it contains. You can then navigate to an item by clicking on it, or see call hierarchy information by right-clicking on the item.

The new Find window provides many new features and uses much less screen real estate than the previous version:

Item templates

Pages: Collection page, Grouped collection page, Item detail page, Split page, User control.

Contracts: File Picker Contract, Search Contract, Share Contract

Code Files

Graphics (C++ DirectX): Compute Shader File, Geometry Shader File, Pixel Shader File, Vertex Shader File.

Expression Blend for Metro style app development

One of the advantages of building HTML-based Metro style apps is that they can run on a wider array of devices than apps built with XAML and C++ or C#. Another advantage is that your Metro style app can use media and visual assets from a web site that you already have.

Document windows
View controls Provides three options to control your app:
- Interactive Mode can be turned on and off, allowing you to interact with the app to get it into different states, which you can then style.
- The error indicator tells you if there are errors in your app and displays the error list in the Results panel.
- The Refresh button lets you restore your app to its initial state after you changed states in Interactive mode.
Views (Design, Code, Split)

Assets panel

CSS Properties panel

The CSS Properties panel in Microsoft Expression Blend 5 for Windows Developer Preview is where you can view and modify the CSS properties of an element that is selected on the artboard or under Live DOM.

A - CSS properties. An expandable and collapsible list of CSS properties that can be sorted by category or by name.

Applied Rules Displays the sources of all the CSS rules that apply to the selected element, including inline, in-document, and external style sheets. The winning rule displays the CSS rule with the highest order of precedence.
View set properties only Check this box to display only those CSS properties that are configured for the selected element.
Category properties When CSS properties are arranged by category, displays all of the properties that belong to the expanded category.
Color editor

Platform panel

The Platform panel in Microsoft Expression Blend 5 for Windows Developer Preview lets you select displays, views, and display options.

Views Select the display view for your app, either portrait, landscape, filled or snapped.
Display Select the display resolution of the device for which you're designing your app.
Show Chrome Uncheck this box to turn off the simulated tablet frame around your app in the Design view.
Override scaling Check this box to emulate the built-in display scaling of the device.
Deploy Target Select the device where your app will be deployed when it builds.

Styles panel

The Styles panel lists all the style sheets attached to the current document and all of the styles defined in them. You can open the Styles panel by clicking Styles on the Window menu.

Search box
Style sheets Displays all style sheets (CSS) attached to the current document.
Styles Displays styles defined within the style sheets.

Attributes panel

The Attributes panel lists attributes for the selected element. You can open the Attributes panel by clicking Attributes on the Window menu.

ID Displays the type and ID of the selected element.
Search box
Attributes

Add a style sheet

CSS styles

By default, Expression Blend for Windows Developer Preview will create new style definitions as inline styles. While that may be sufficient for creating quick prototypes, it can be difficult to maintain inline style definitions for your production app. A best practice is to create and maintain your styles by using an external style sheet.

In the Styles panel, click the drop-down menu arrow next to Current document (defaultStart.html). Select Link a Style Sheet.

Add a style rule

To modify the size of the gameBody div, we'll add a new style rule for the gameBody element in our external style sheet.

In the CSS Properties panel, click the drop-down menu arrow next to Applied Rules and select Create style rule from selected element ID: gameBody. A new style rule is added to the style sheet and the selector for the new style rule is automatically set to #gameBody.

For any element selected in the Live DOM panel, the Applied Rules panel shows all style rules that are applied to the element, in the order of application. The #gameBody tag is currently selected, indicating that this is the currently active rule.

The Applied Rules panel also includes an additional entry labeled winning. This is a virtual rule that collects the properties that have the highest order of precedence and specificity across all other rules and their values. The winning rule is a convenient way to quickly adjust properties that are already set in their appropriate places, without having to search for the right rule, or to worry about modifying the wrong rule.

Set style rules for a property

In the Live DOM panel, select #gameBody.
In the CSS Properties panel, expand the Sizing category.
Click width and enter 100%. Click height and enter 100%.

Make the layout resizable

Microsoft Windows Developer Preview automatically adds appropriate scaling factors for high-pixel-density displays and Microsoft Expression Blend 5 for Windows Developer Preview provides the ability to preview how your design looks and behaves when the app is resized.

The CSS grid

Like HTML table layouts, CSS grids are based on rows and columns. Unlike the HTML table element, the rows and columns for grid layout are defined in CSS, not in HTML, keeping your semantic markup free from markup devoted to layout. Further, CSS grid layout offers precise control over grid behavior during resize events.

Rows and columns can be defined to have a fixed size. Alternatively, rows or columns can be defined to have a fractional size, causing them to resize relative to a size change of the grid. For example, if one row is defined 1fr and another 2fr, the grid will size the two rows so that the second one is twice as big as the first one, no matter what the size of the grid. You can also define rows or columns to size to fit their content by using auto. The grid has many more options that make layout within very powerful and flexible. Grid layout can be applied to any block element by using the display property in the -ms-grid setting.

To enable the grid

In the Live Dom panel, select gameBody.
In the Applied Rules section of the CSS Properties panel, make sure that either winning or #gameBody is selected.
In the CSS Properties panel, expand the Layout section.
Click the display drop-down menu and select –ms-grid.

As soon as this property is set, all of the grid content stacks up in the top left corner.

To create the grid

Ensure that gameBody is selected in the Live DOM panel and that either winning or #gameBody is selected in the Applied Rules section of the CSS Properties panel.
Move your mouse cursor over the top grid adorner. An orange insert column adorner appears.
Click to add the grid column adorner.

In the CSS Properties panel, expand the Grid section.

To set a column to a fixed size

Move the mouse pointer to the top of a grid column. The Fraction (fr)/Fixed (px) drop-down is displayed (the default setting is fr for fractional):

Click the fixed/fractional drop-down and select px to set the selected column to fixed size.

Align content to the grid

We want to store the grid positioning information in the CSS rule with the #gameTitle selector. In order for this to happen, you must select either winning rule or the #gameTitle rule in Applied Rules for the title element. If the #gameTitle rule is selected, Expression Blend for Windows Developer Preview will attempt to write new properties to it. If the winning rule is selected, the write target for the new property is determined as follows:

If winning rule is selected, a property that is already set is written to the same rule where it was originally defined.
If winning rule is selected, Expression Blend for Windows Developer Preview tries first to write a new property to a rule with an ID selector. In the case of the gameTitle element, this would be #gameTitle.
If winning rule selected and there is no appropriate ID rule defined, Expression Blend for Windows Developer Preview writes the style to the inline rule if the inline rule is accessible for writing (if the element is dynamically generated in JavaScript, Expression Blend cannot store properties for the inline style)

Position

In the CSS Properties panel, click in the View set properties only checkbox to display an overview of the properties set for gameTitle.

To position the title in the grid

In the Applied Rules section of the CSS Properties panel, select either winning or #gameTitle.
In the CSS Properties panel, expand the Grid category.
Set the -ms-grid-column property to 4 (CSS columns and rows are counted starting with 1).

To fix the title alignment

In the Grid category, set -ms-grid-row-align to end using the combo box.
In the Layout category, set margin-bottom to 0.

Positioning button

Select the Start the Game button on the artboard.

In the CSS Properties panel, click the drop-down menu arrow next to Applied Rules and select Create style rule from selected element class: gameButtons. A new style rule is created.

Building and running app

The Simulator target can emulate a touch-screen device with the following options:

Mouse mode The mouse pointer behaves like a traditional mouse pointer.
Touch emulation The mouse pointer changes to emulate touch interaction.
Touch emulation pinch-zoom The mouse pointer changes to emulate a pinch-zoom motion. The touch emulation pinch-zoom interaction is controlled by the mouse wheel.
Touch emulation rotate The mouse pointer changes to emulate a rotation motion. The Touch emulation rotate emulations is controlled by the mouse wheel.
Rotate simulator to the right The simulator is rotated 90 degrees to the right.
Rotate simulator to the left The simulator is rotated 90 degrees to the left.
Change resolution The simulator is changed to the resolution you select from a list.

c.d.n