---
title: "handActivationBehavior(_:)"
framework: swiftui
role: symbol
role_heading: Instance Method
path: "swiftui/gesture/handactivationbehavior(_:)"
---

# handActivationBehavior(_:)

Customizes the activation behavior for a gesture when driven by hand or hand-like input.

## Declaration

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

```

## Parameters

- `behavior`: The hand activation behavior to use for the gesture.

## Return Value

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

## Discussion

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                 // ...             }     )