Attempts to transition the state machine from its current state to a state of the specified class.
SDKs
- iOS 9.0+
- macOS 10.11+
- Mac Catalyst 13.0+
- tvOS 9.0+
Framework
- Gameplay
Kit
Declaration
Parameters
stateClassThe class of state into which to attempt a transition.
Return Value
true if the transition was successful; otherwise false.
Discussion
You build a state machine by creating a unique GKState subclass for each distinct state possible for the machine. The is method of each state object determines which other states a state machine is allowed to transition into from that state. Calling this method first tests whether a transition from the current state to the specified state is valid; if not, this method returns false.
If a transition is allowed, the state machine sends the will message to its current state object. Then, the new state object replaces the value of the current property. Finally, the state machine sends the did message to the new current state object, and this method returns true.
A newly created state machine’s current property is nil—to choose and enter an initial state, use the enter(_:) method. In this case, the enter(_:) call always succeeds.