ViewportTransition

@_spi(Experimental)
public protocol ViewportTransition : AnyObject

ViewportTransition is a protocol that Viewport depends on as it orchestrates transitions to and from different ViewportStates.

MapboxMaps provides implementations of ViewportTransition that can be created and configured via methods on Viewport. Applications may also define their own implementations to handle advanced use cases not covered by the provided implementations.

  • Runs the transition to toState.

    The completion block must be invoked with true if the transition completes successfully. If the transition fails, invoke the completion block with false.

    If the returned Cancelable is canceled, it not necessary to invoke the completion block (but is safe to do so — it will just be ignored).

    Transitions should handle the possibility that the “to” state might fail to provide a target camera in a timely manner or might update the target camera multiple times during the transition (a “moving target”).

    Declaration

    Swift

    func run(to toState: ViewportState,
             completion: @escaping (_ success: Bool) -> Void) -> Cancelable

    Parameters

    toState

    The target state for the transition.

    completion

    A block that must be invoked when the transition is complete. Must be invoked on the main queue.

    success

    A flag to indicate whether the transition was successful.

    Return Value

    a Cancelable that can be used to terminate the transition. If cancel() is invoked, the transition must immediately stop updating the camera and cancel any animations that it started.