Returns the linear velocity for a specified dynamic item.
The dynamic item whose linear velocity you want to get.
The linear velocity of the specified dynamic item, in points per second.
Configuring a Dynamic Item Behavior
var friction: CGFloat
The linear resistance for the behavior’s dynamic items when two slide against each other.
var resistance: CGFloat
The linear resistance for the behavior’s dynamic items, which reduces their linear velocity over time.
var isAnchored: Bool
A Boolean value indicating whether the item is anchored to its current position.