MICROSOFT_PRESS_EBOOK_PROGRAMMING_WINDOWS_8_APPS_WITH_HTML_CSS_AND_JAVASCRIPT_PDF

setAccountPicturesAsync (for providing small and large images as well as a video from
StorageFile objects), and setAccountPictureFromStreamAsync and
setAccount-PicturesFromStreamAsync (which do the same given IRandomAccessStream objects
instead). In each case the async result is a SetAccountPictureResult value: success, failure,
changeDisabled (accountPictureChangeEnabled is false), large-OrDynamicError (the picture is
too large), fileSizeError (file is too large), or video-FrameSizeError (video frame size is too
large),
• The accountpicturechanged event signals when the user picture(s) have been altered.
Remember that because this event originates within WinRT you should call
removeEvent-Listener if you aren’t listening for this event for the lifetime of the app.
These features are demonstrated in the Account picture name sample. Scenario 1 retrieves the
display name, Scenario 2 retrieves the first and last name (if available), Scenario 3 retrieves the account
pictures and video, and Scenario 4 changes the account pictures and video and listens for picture
changes.
Tip To obtain the profile picture from Live Connect, the exact API call is as follows:
https://apis.live.net/v5.0/me/picture?access_token=.
One other bit that this sample demonstrates is the Account Picture Provider declaration in its
manifest, which causes the app to appear within PC Settings > Personalize under Create an Account
Picture:
In this case the sample doesn’t actually provide a picture directly but activates into Scenario 4. A real
app, like the Camera app that’s also in PC Settings by default, will automatically set the account picture
when one is acquired through its UI. How does it know to do this? The answer lies in a special URI
scheme through which the app is activated. That is, when you declare the Account Picture Provider
declaration in the manifest, the app will be activated with the activation kind of protocol (see Chapter
12, “Contracts”), where the URI scheme specifically starts with ms-accountpictureprovider. You can see
how this is handled in the sample’s js/default.js file:
if (eventObject.detail.kind === Windows.ApplicationModel.Activation.ActivationKind.protocol) {
// Check if the protocol matches the "ms-accountpictureprovider" scheme
if (eventObject.detail.uri.schemeName === "ms-accountpictureprovider") {
669