Two small bits today about a couple of WinRT APIs, or, in the first case, the lack thereof.
Developers sometimes ask how to get at the system colors that the user has assigned to the Start screen. The answer is simply that you can’t. The reason for this is that to prevent apps from spoofing system UI, such as permissions dialogs, which would deceive the user as to who is asking the question. In the design of Windows Store apps, color is specifically used as a branding element for apps, so the system colors are also a branding for Windows. Apps should always use their own coloring for UI.
The second and completely unrelated bit comes from a forum question where a developer wanted to schedule thousands of tile updates in advance (up to the overall limit of 4096!). In some circumstances he wanted to clear all those out and start afresh, but would that the TileUpdater.clear() method didn’t work for this. This is a simply misunderstanding: clear removed only the currently displayed update from the tile. To remove scheduled updates you instead need to use TileUpdater.removeFromSchedule. That docs page also shows how to use this in conjunction with getScheduledTileNotifications to clear all scheduled updates.