MICROSOFT_PRESS_EBOOK_PROGRAMMING_WINDOWS_8_APPS_WITH_HTML_CSS_AND_JAVASCRIPT_PDF

FIGURE 13-19 The user consent prompt when an app requests lock screen access.
FIGURE 13-20 The lock screen option on the Permissions settings panel for apps that request access.
For a complete demonstration, refer to the Lock screen apps sample. In Scenario 1 it shows how to
again request access to the lock screen and check the result, which is a value from the Background-
AccessStatus enumeration. It also shows querying for and removing that access with the
getAccessStatus and removeAccess methods of BackgroundExecutionManager.
Scenario 2 then demonstrates sending badge updates to the lock screen, along with a text tile
update if the app happens to be the single one selected for that privilege. There is nothing particular in
this process where the lock screen is concerned, however: such updates happen exactly as they do for
the primary app tile. It’s just that those updates are also reflected on the lock screen. In the case of
badges, the badge glyph will appear along with the app’s Badge Logo in the Application UI >
Notifications section of the manifest. (Refer back to Figure 13-10.) To repeat from earlier, this graphic
must have white or transparent pixels, and the three scale sizes are 24x24 (100%), 33x33 (140%), and
43x43 (180%).
Scenario 3, finally, demonstrates that secondary tiles can be added to the lock screen as well,
irrespective of the app tile. To make a secondary tile available for the lock screen, assuming that the app
has requested lock screen access already, you need to set those two properties of Windows.UI.-
StartScreen.SecondaryTile that we mentioned long ago: lockScreenBadgeLogo and
lockScreenDisplayBadgeAndTileText. If the secondary tile is on the Start screen, these properties will
also make it available on the PC Settings page for the lock screen.
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