When a photo has been zoomed, the gesture recognizer should not respond to swipe up or down to dismiss.

[albertgh]

If drag to left or right at the begining, then continue drag to up or down works fine.
But if drag to up or down at the begining it respond to dismiss action.
I think the reason we zoom a photo is for drag it to any orientation,
and at that specific case we still have a done button do the dismiss action

And landscape photo zooms weird, there is too much black background.
I think it's the height of the scrollView it too high.

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Sorry for my poor English.