如何使 SwiftUI 上的 LongPressGesture 失敗

Question

當我將手指從圖像上移開時，我試圖用 maximumDistance 使 LongPressGesture 失敗，但這不起作用，它會一直打印消息“Pressed”

struct ContentView: View {
@GestureState private var isDetectingPress = false

var body: some View {
    Image(systemName: "trash")
        .resizable().aspectRatio(contentMode: .fit)
        .frame(width: 100, height: 100)
        .scaleEffect(isDetectingPress ? 0.5 : 1)
        .animation(.easeInOut(duration: 0.2))
        .gesture(LongPressGesture(minimumDuration: 0.01, maximumDistance: 10).sequenced(before:DragGesture(minimumDistance: 0).onEnded {_ in
            print("Pressed")
        })
            .updating($isDetectingPress) { value, state, _ in
                switch value {
                    case .second(true, nil):
                        state = true
                    default:
                        break
                }
        })
    }
}

Answer 1

更改updating修飾符以檢測是否存在拖動量：

.updating($isDetectingPress) { value, state, _ in
    switch value {
    case .second(true, nil):
        state = true
    case .second(true, _): // add this case to handle `non-nil` drag amount
        state = false
    default:
        break
    }

並在DragGesture本身中為DragGesture設置最小距離（例如 100）：

DragGesture(minimumDistance: 100)

而不是LongPressGesture ：

//LongPressGesture(minimumDuration: 0.01, maximumDistance: 100) // remove `maximumDistance`
LongPressGesture(minimumDuration: 0.01)