handActivationBehavior(_:)

Declaration

@MainActor @preconcurrency func handActivationBehavior(_ behavior: HandActivationBehavior) -> some Gesture<Self.Value>

Parameters

• behavior:

  The hand activation behavior to use for the gesture.

Return Value

A new gesture with a preference to activate with the provided behavior.

Discussion

Use automatic to allow a gesture to activate with default system behaviors. Use pinch when a gesture should only trigger when the hand is pinched.

For example, in a 3D chess application, a DragGesture that enables movement of the pieces could use the pinch behavior to ensure that piece movement is only possible when a hand is pinched in order to avoid pushing the piece around by only touching it:

Model3D(named: "Pawn")
    .gesture(
        DragGesture()
            .handActivationBehavior(.pinch)
            .updating($chessDragState) { value, state, _ in
                // ...
            }
    )