Slider and IsDirectionReversed–Why doesn’t my app work on WP8 (part 6 of N)

Just when you thought all the bugs must have been ironed out by now, you stumble across a new one.

I’ve recently been updating all of my apps to Visual Studio 2013 so support will be simpler in future, and as a result started porting to WP8 from our old WP7 codebase.

Of course, everything is supposed to just work.  Today we’ll focus on the IsDirectionReversedProperty, which as will see should really be called IsDirectionReversedProperly!

Try sticking this in your WP app:

<Slider Orientation="Horizontal" Maximum="10" IsDirectionReversed="True" />

Can you see where this is going?

Now add Minimum="5" and be amazed that this slipped through testing.

It’s broken on the 720p emulator.  It’s broken on my Lumia 920 with GDR3.  It’s not broken in a WP7 app though.

So, I wonder how Microsoft can fix this out in the wild, (though it only seems to work in any kind of reasonable way if Minimum is set to 0).  Someone may be depending on this behavior.