Question

对于SwiftUI，默认按钮行为等同于UIKit的“在内部向上触摸”，当您的手指触摸按钮然后在按钮范围内抬起时，该行为会激活。

是否可以将其更改为“触地”，以便在您的手指触摸按钮时立即执行动作关闭？

Answer 1

您可以使用最小距离为零的DragGesture，并为DOWN（onChanged（））或UP（onEnded（））定义闭包：

struct ContentView: View {
    @State private var idx = 0

    var body: some View {
        let g = DragGesture(minimumDistance: 0, coordinateSpace: .local).onChanged({
            print("DOWN: \($0)")
        }).onEnded({
            print("UP: \($0)")
        })

        return Rectangle().frame(width: 100, height: 50).gesture(g)
    }
}

Answer 2

您可以创建自定义视图修饰符：

extension View {
    func onTouchDownGesture(callback: @escaping () -> Void) -> some View {
        modifier(OnTouchDownGestureModifier(callback: callback))
    }
}

private struct OnTouchDownGestureModifier: ViewModifier {
    @State private var tapped = false
    let callback: () -> Void

    func body(content: Content) -> some View {
        content
            .simultaneousGesture(DragGesture(minimumDistance: 0)
                .onChanged { _ in
                    if !self.tapped {
                        self.tapped = true
                        self.callback()
                    }
                }
                .onEnded { _ in
                    self.tapped = false
                })
    }
}

struct MyView: View {
    var body: some View {
        Text("Hello World")
            .onTouchDownGesture {
                print("View did tap!")
            }
    }
}

Answer 3

我设法通过一个简单的按钮修饰符实现了这一点：

struct TouchedButtonStyle: PrimitiveButtonStyle {
    func makeBody(configuration: Configuration) -> some View {
        configuration
            .label
            .onTapGesture(perform: configuration.trigger)
    }
}

现在您只需将修饰符分配给您的按钮：

YourButton()
    .buttonStyle(TouchedButtonStyle())

是否有任何UIUI等同于UIKit的“向下触摸”的SwiftUI按钮，即手指触摸时激活按钮？

3 个答案: