How to detect live changes on TextField in SwiftUI?

dylankbuckley picture dylankbuckley · Sep 10, 2019 · Viewed 12.2k times · Source

I have a simple TextField that binds to the state 'location' like this,

TextField("Search Location", text: $location)

I want to call a function each time this field changes, something like this:

TextField("Search Location", text: $location) {
   self.autocomplete(location)
}

However this doesn't work. I know that there are callbacks, onEditingChanged - however this only seems to be triggered when the field is focussed.

How can I get this function to call each time the field is updated?

Answer

kontiki picture kontiki · Sep 10, 2019

You can create a binding with a custom closure, like this:

struct ContentView: View {
    @State var location: String = ""

    var body: some View {
        let binding = Binding<String>(get: {
            self.location
        }, set: {
            self.location = $0
            // do whatever you want here
        })

        return VStack {
            Text("Current location: \(location)")
            TextField("Search Location", text: binding)
        }

    }
}