如何为SwiftUI视图条件式添加accessibilityAction？

下面给你几种实用的实现方式，解决无法直接用if语句添加accessibilityAction的问题：

方法1：利用通用.if扩展实现链式条件Modifier #

给View添加一个通用扩展，让你可以在Modifier链里直接根据布尔值决定是否应用指定操作：

// 先给View添加通用的.if扩展
extension View {
    @ViewBuilder
    func `if`<Content: View>(_ condition: Bool, transform: (Self) -> Content) -> some View {
        if condition {
            transform(self)
        } else {
            self
        }
    }
}

// 使用示例
@State private var addActionToButton = false

Button {
    print("Button tapped")
} label: {
    Text("Button title")
}
.if(addActionToButton) { view in
    view.accessibilityAction(named: "Button action") {
        print("Button action triggered")
    }
}

方法2：自定义带isEnabled参数的accessibilityAction扩展 #

仿照accessibilityLabel的设计，给View写一个扩展，让它直接支持启用/禁用开关：

// 自定义扩展
extension View {
    func accessibilityAction(named name: LocalizedStringKey, isEnabled: Bool, action: @escaping () -> Void) -> some View {
        modifier(OptionalAccessibilityAction(name: name, isEnabled: isEnabled, action: action))
    }
}

struct OptionalAccessibilityAction: ViewModifier {
    let name: LocalizedStringKey
    let isEnabled: Bool
    let action: () -> Void
    
    func body(content: Content) -> some View {
        isEnabled ? content.accessibilityAction(named: name, action) : content
    }
}

// 使用方式和accessibilityLabel完全一致
@State private var addActionToButton = false

Button {
    print("Button tapped")
} label: {
    Text("Button title")
}
.accessibilityAction(named: "Button action", isEnabled: addActionToButton) {
    print("Button action triggered")
}

方法3：用ViewBuilder包装视图分支 #

把按钮放在ViewBuilder的条件分支里，根据布尔值生成带/不带无障碍操作的视图：

@State private var addActionToButton = false

@ViewBuilder
var conditionalButton: some View {
    let baseButton = Button {
        print("Button tapped")
    } label: {
        Text("Button title")
    }
    
    if addActionToButton {
        baseButton.accessibilityAction(named: "Button action") {
            print("Button action triggered")
        }
    } else {
        baseButton
    }
}

// 在body中直接使用这个自定义视图
var body: some View {
    conditionalButton
}

内容的提问来源于stack exchange，提问作者Duncan C