SwiftUI LongPressGesture 需要很长时间才能识别 TapGesture 何时也存在

Question

我想识别同一商品上的 TapGesture 和 LongPressGesture。它工作正常，除了以下例外：LongPressGesture 单独在我指定的持续时间（0.25 秒）后响应，但是当我将它与TapGesture 结合使用时，至少需要 1 秒——我找不到一种让它更快响应的方法。这是一个演示：

这是它的代码：

struct ContentView: View {
    @State var message = ""

    var body: some View {
        Circle()
            .fill(Color.yellow)
            .frame(width: 150, height: 150)
            .onTapGesture(count: 1) {
                message = "TAP"
            }
            .onLongPressGesture(minimumDuration: 0.25) {
                message = "LONG\nPRESS"
            }
            .overlay(Text(message)
                        .font(.title).bold()
                        .multilineTextAlignment(.center)
                        .allowsHitTesting(false))
    }
}

请注意，除了 LongPress 的持续时间长于 0.25 秒之外，它工作正常。

有什么想法吗？提前致谢！

Answer 1

为了在项目中拥有一些适合每个人需要的多手势，Apple 提供的只是普通手势，将它们混合在一起以达到想要的手势有时会变得很棘手，这是一种拯救，没有 问题或错误！

这里有一个名为 interactionReader 的自定义 zero issue 手势，我们可以将其应用于任何 View。 LongPressGesture 和 TapGesture 同时。

---

---

import SwiftUI

struct ContentView: View {
    
    var body: some View {
        
        Circle()
            .fill(Color.yellow)
            .frame(width: 150, height: 150)
            .interactionReader(longPressSensitivity: 250, tapAction: tapAction, longPressAction: longPressAction, scaleEffect: true)
            .animation(Animation.easeInOut(duration: 0.2))
        
    }
    
    func tapAction() { print("tap action!") }
    
    func longPressAction() { print("longPress action!") }
    
}

---

struct InteractionReaderViewModifier: ViewModifier {
    
    var longPressSensitivity: Int
    var tapAction: () -> Void
    var longPressAction: () -> Void
    var scaleEffect: Bool = true
    
    @State private var isPressing: Bool = Bool()
    @State private var currentDismissId: DispatchTime = DispatchTime.now()
    @State private var lastInteractionKind: String = String()
    
    func body(content: Content) -> some View {
        
        let processedContent = content
            .gesture(gesture)
            .onChange(of: isPressing) { newValue in
                
                currentDismissId = DispatchTime.now() + .milliseconds(longPressSensitivity)
                let dismissId: DispatchTime = currentDismissId
                
                if isPressing {
                    
                    DispatchQueue.main.asyncAfter(deadline: dismissId) {
                        
                        if isPressing { if (dismissId == currentDismissId) { lastInteractionKind = "longPress"; longPressAction() } }
                        
                    }
                    
                }
                else {
                    
                    if (lastInteractionKind != "longPress") { lastInteractionKind = "tap"; tapAction() }
                    
                    DispatchQueue.main.asyncAfter(deadline: .now() + .milliseconds(50)) {lastInteractionKind = "none"}
                    
                    
                }
                
            }
        
        return Group {
            
            if scaleEffect { processedContent.scaleEffect(lastInteractionKind == "longPress" ? 1.5: (lastInteractionKind == "tap" ? 0.8 : 1.0 )) }
            else { processedContent }
            
        }

    }
    
    var gesture: some Gesture {
        
        DragGesture(minimumDistance: 0.0, coordinateSpace: .local)
            .onChanged() { _ in if !isPressing { isPressing = true } }
            .onEnded() { _ in isPressing = false }
        
    }
    
}

---

extension View {
    
    func interactionReader(longPressSensitivity: Int, tapAction: @escaping () -> Void, longPressAction: @escaping () -> Void, scaleEffect: Bool = true) -> some View {
        
        return self.modifier(InteractionReaderViewModifier(longPressSensitivity: longPressSensitivity, tapAction: tapAction, longPressAction: longPressAction, scaleEffect: scaleEffect))
        
    }
    
}

Answer 2

嗯，这不是很漂亮，但效果很好。它记录每次点击/按下的开始，如果它在 0.25 秒之前结束，它认为它是 TapGesture，否则它认为它是 LongPressGesture：

struct ContentView: View {
    @State var pressInProgress = false
    @State var gestureEnded = false
    @State var workItem: DispatchWorkItem? = nil
    @State var message = ""

    var body: some View {

        Circle()
            .fill(Color.yellow)
            .frame(width: 150, height: 150, alignment: .center)
            .overlay(Text(message)
                         .font(.title).bold()
                         .multilineTextAlignment(.center)
                         .allowsHitTesting(false))
            .gesture(
                DragGesture(minimumDistance: 0, coordinateSpace: .global)
                    .onChanged { _ in
                        guard !pressInProgress else { return }
                        pressInProgress = true
                        workItem = DispatchWorkItem {
                            message = "LONG\nPRESSED"
                            gestureEnded = true
                        }
                        DispatchQueue.main.asyncAfter(deadline: .now() + 0.25, execute: workItem!)
                }
                .onEnded { _ in
                    pressInProgress = false
                    workItem?.cancel()
                    guard !gestureEnded else { // moot if we're past 0.25 seconds so ignore
                        gestureEnded = false
                        return
                    }
                    message = "TAPPED"
                    gestureEnded = false
                }
        )
    }
}

如果有人能想到一个实际使用 LongPressGesture 和 TapGesture 的解决方案，我会更喜欢这个！

Answer 3

LongPressGesture 有另一个完成，可以在用户第一次触地时执行一个动作......并在最短持续时间再次执行。像这样的东西可以吗？

struct LongTapTest: View {
    @State var message = ""

    var body: some View {
        Circle()
            .fill(Color.yellow)
            .frame(width: 150, height: 150)
            .onLongPressGesture(minimumDuration: 0.25, maximumDistance: 50, pressing: { (isPressing) in
            if isPressing {
                // called on touch down
            } else {
                // called on touch up
                message = "TAP"
            }
        }, perform: {
            message = "LONG\nPRESS"
        })
            .overlay(Text(message)
                        .font(.title).bold()
                        .multilineTextAlignment(.center)
                        .allowsHitTesting(false))
    }
}