Versuchen, die Eigenschaft directionalLockEnabled von UIScrollView zu verwenden
directionalLockEnabled A Boolean value that determines whether
scrolling is disabled in a particular direction
@property(nonatomic, getter=isDirectionalLockEnabled) BOOL
directionalLockEnabled Discussion If this property is NO, scrolling is
permitted in both horizontal and vertical directions. If this property
is YES and the user begins dragging in one general direction
(horizontally or vertically), the scroll view disables scrolling in
the other direction. If the drag direction is diagonal, then scrolling
will not be locked and the user can drag in any direction until the
drag completes. The default value is NO
Availability Available in iOS 2.0 and later. Declared In
UIScrollView.h