swift - Override the functionality of the button from another View?

Question

I got a re-usable searchbar in a separate view that looks like this:

struct SearchBar: View {
    
    @Binding var searchText: String
    @Binding var isSearching: Bool
    
    var body: some View {
        HStack {
            HStack {
                TextField("Search terms here", text: $searchText)
            }
            .onTapGesture(perform: {
                isSearching = true
            })
            .overlay(
                HStack {
                    Image(systemName: "magnifyingglass")
                    
                    if isSearching {
                        Button(action: { searchText = "" }, label: {
                            Image(systemName: "xmark.circle.fill")     
                        })
                    }   
                }
            )
            if isSearching {
                Button(action: {
                    isSearching = false
                    searchText = ""
                    
                }, label: {
                    Text("Cancel")
                        
                })
            }
            
        }
    }
}

And I'm using the SearchBar in multiple views, like this:

SearchBar(searchText: $textFieldSearch, isSearching: $isSearching)

Is there a way to override/append the functionality of the cancel button:

Button(action: {
   isSearching = false
   searchText = ""
   // pass more functionality here dynamically
 }, 
  label: {
  Text("Cancel")   
})

In some Views, I need to do some additional stuff besides clearing the searchText field and setting isSearching to false.

Answer 1

你可以使用闭包。在这里，我创建了一个取消按钮关闭操作并将其设置为可选。

struct SearchBar: View {
    
    @Binding var searchText: String
    @Binding var isSearching: Bool
    var cancel: (() -> Void)? // <== Here
    
    var body: some View {
        HStack {
            HStack {
                TextField("Search terms here", text: $searchText)
            }
            .onTapGesture(perform: {
                isSearching = true
            })
            .overlay(
                HStack {
                    Image(systemName: "magnifyingglass")
                    
                    if isSearching {
                        Button(action: { searchText = "" }, label: {
                            Image(systemName: "xmark.circle.fill")
                        })
                    }
                }
            )
            if isSearching {
                Button(action: {
                    isSearching = false
                    searchText = ""
                    cancel?() // <== Here
                }, label: {
                    Text("Cancel")
                    
                })
            }
            
        }
    }
}

用法

SearchBar(searchText: $textFieldSearch, isSearching: $isSearching)
SearchBar(searchText: $textFieldSearch, isSearching: $isSearching) {
    // Cancel Action
}

Answer 2

如果您需要额外的操作，那么您可以注入onCancel副作用，例如

struct SearchBar: View {
    
    @Binding var searchText: String
    @Binding var isSearching: Bool
    var onCancel: () -> Void = {}     // << default does nothing

    ...

            if isSearching {
                Button(action: {
                    isSearching = false
                    searchText = ""
                    onCancel()            // << here !!
                }, label: {
                    Text("Cancel")
                    
                })
            }

并像您一样以默认方式使用或提供副作用，例如

SearchBar(searchText: $textFieldSearch, isSearching: $isSearching) {
  // side effect is here
}