Combine12.swift

let selectedFilter = PassthroughSubject<String, Never>()
let searchText =  NotificationCenter.default
    .publisher(for: UITextField.textDidChangeNotification, object: searchTextField)
    .map( { ($0.object as! UITextField).text } )
    .debounce(for: .milliseconds(500), scheduler: RunLoop.main)
    .eraseToAnyPublisher()


let publisher = Publishers.CombineLatest(selectedFilter,searchText, transform: { selectedFilter, searchText in
    "\(selectedFilter) \(searchText)"
})

_ = publisher.sink { value in
    print(value)
}