ZoomAnimator

class ZoomAnimator : NSObject

A custom zoom animation for the transition from an ImageCollectionViewController to an ImagePagingCollectionViewController when a cell is tapped. It also handles the retraction transition. It was built to mimic the transition used in the native iPhone Photos app.

This custom animation was documented and explained in complete detail in the links provided below.

See also

GitHub EditPlantLevelManager_notes.md.

  • The delegate being animated from.

    Declaration

    Swift

    weak var fromDelegate: ZoomAnimatorDelegate?

  • The delegate being animated to.

    Declaration

    Swift

    weak var toDelegate: ZoomAnimatorDelegate?

  • A Boolean for is the animation is presenting (or retracting)

    Declaration

    Swift

    var isPresenting: Bool

  • The image view that is animated from the location of the source image to the destination image.

    Declaration

    Swift

    var transitionImageView: UIImageView?

  • The animation for the zoom in transition.

    See also

    GitHub EditPlantLevelManager_notes.md.

    Declaration

    Swift

    fileprivate func animateZoomInTransition(using transitionContext: UIViewControllerContextTransitioning)

    Parameters

    transitionContext

    The context provided to a transtion that has information about the source. and destination view controllers.

  • The animation for the zoom out transition.

    See also

    GitHub EditPlantLevelManager_notes.md.

    Declaration

    Swift

    fileprivate func animateZoomOutTransition(using transitionContext: UIViewControllerContextTransitioning)

    Parameters

    transitionContext

    The context provided to a transtion that has information about the source and destination view controllers.

  • Calculates the final frame size for an image during the zoom-in transition.

    Declaration

    Swift

    private func calculateZoomInImageFrame(image: UIImage, forView view: UIView) -> CGRect

    Parameters

    image

    The image being zoomed.
    view

    The destination view.

    Return Value

    A rectangle with the dimensions for the destination of the zoom.

  • The duration of the transition. It is currently set manually to be 0.5 seconds to zoom in (during presentation) and 0.25 to zoom out (not during presentation)

    Declaration

    Swift

    func transitionDuration(using transitionContext: UIViewControllerContextTransitioning?) -> TimeInterval

    Parameters

    transitionContext

    The context provided to a transtion that has information about the source and destination view controllers.

    Return Value

    A time interval in seconds.

  • The function called during transition. It is used here to decide which animation to use.

    Declaration

    Swift

    func animateTransition(using transitionContext: UIViewControllerContextTransitioning)