@class NSPointerArray; @interface UIInteractionProgress : NSObject { NSPointerArray *_observers; double _previousPercentComplete; double _previousUpdateTime; double _mostRecentUpdateTime; long long _atLeastTwoUpdates; } @property (readonly, nonatomic) double percentComplete; @property (readonly, nonatomic) double velocity; - (id)init; - (void)endInteraction:(BOOL)a0; - (void)setPercentComplete:(double)a0; - (void)removeProgressObserver:(id)a0; - (id)description; - (void)addProgressObserver:(id)a0; - (void).cxx_destruct; - (unsigned long long)_indexOfObserver:(id)a0; - (void)endInteraction:(BOOL)a0 finalVelocity:(double)a1; - (long long)numberOfObservers; @end