SwiftUI 中列表的多个过滤器

Question

如何过滤多个列表 切换？需要过滤红色、黄色和绿色切换，默认情况下（所有切换关闭）显示所有 Array 未过滤

struct Test: View {
    @State var redToggle: Bool = false
    @State var yellowToggle: Bool = false
    @State var greenToggle: Bool = false
    
    let testArray = ["red", "green", "yellow", "mint", "red", "green", "white"]
    
    var body: some View {
        
        VStack {
            List {
                    ForEach(testArray.filter({
                        return (
                             (!redToggle && $0.description != "red") ||
                             (!yellowToggle && $0.description == "red")
                             
                          //need add here some filters for green toggle 
                            
                        )
                    }), id: \.self) { colors in
                        Text("Color are \(colors)")
                    }
            }
            Spacer()
            HStack(alignment: .center) {
                Toggle(isOn: $redToggle) {
                    Text("Red")
                }.toggleStyle(.switch)
                
                Toggle(isOn: $yellowToggle) {
                    Text("Yellow")
                }.toggleStyle(.switch)
                
                Toggle(isOn: $greenToggle) {
                    Text("Green")
                }.toggleStyle(.switch)
            }
        }
        }
    }

Answer 1

如果您希望能够从列表中过滤多个内容，您可以尝试这样的操作

import SwiftUI

struct MultipleFilterView: View {
    let testArray = ["red", "green", "yellow", "mint", "red", "green", "white"]
    //Dictionary that contains your filter word and wether it is selected or now
    //If you want more options just add them here
    @State var keywordDict: [String: Bool] = ["red": false, "yellow": false, "green": false]
    //An array that contains all the selected keys
    var selectedKeys: [String]{
        keywordDict.keys.filter({ key in
            keywordDict[key] ?? false
        })
    }
    //identify if the user has selected items
    var hasSelectedItem: Bool{
        var results = false
        //returns false unless it finds a true in the dictionary
        //https://whatis.techtarget.com/definition/logic-gate-AND-OR-XOR-NOT-NAND-NOR-and-XNOR
        keywordDict.values.forEach({
            results = results || $0
        })
        return results
    }
    //List will show the selected items
    var filteredList: [String]{
        testArray.filter({ value in
            selectedKeys.contains(where: {
                $0 == value
            })
        })
    }
    var body: some View {
        VStack {
            List {
                //Show the filtered list if the user has selected an item
                ForEach(hasSelectedItem ? filteredList: testArray, id: \.self) { colors in
                    Text("Color is \(colors)")
                }
            }
            Spacer()
            HStack(alignment: .center) {
                //Create a toggle for every key
                //You need a custom Binding for a dictionary
                ForEach(keywordDict.keys.sorted(by: <), id:\.self, content: { key in
                    Toggle(key, isOn: Binding(get: {
                        keywordDict[key] ?? false
                    }, set: {
                        keywordDict[key] = $0
                    })).toggleStyle(.switch)
                })
            }
        }
    }
}
struct MultipleFilterView_Previews: PreviewProvider {
    static var previews: some View {
        //SingleFilterView()
        MultipleFilterView()
    }
}