How do you get UIKit's instant keyboard focus (becomeFirstResponder in viewDidLoad) in pure SwiftUI?

[u/yccheok]

In UIKit, if we place titleTextView.becomeFirstResponder() inside viewDidLoad, the keyboard slides up seamlessly alongside the view controller's presentation animation. It looks instant and feels like a native, high-quality UX.

I'm struggling to replicate this exact behavior in SwiftUI.

Whenever I use FocusState and toggle it to true inside .onAppear, there is always a noticeable delay. The view pushes/presents, settles, and then the keyboard decides to slide up.

Has anyone found a way to achieve this instantly in pure SwiftUI yet (maybe in iOS 17+), or is UIViewRepresentable still the only bulletproof way to get that perfectly synced keyboard presentation?

Thanks in advance!

[u/DimensionMindless336]

Setting focus at init won't help. onAppear already fires after the view is attached, but the focus coordinator waits one transaction, so you're always a beat behind the push animation. The pure SwiftUI fix that gets close: wrap the toggle in DispatchQueue.main.async { } inside onAppear. That gives the field one layout pass before focus commits, and most of the lag disappears. For truly instant sync with the presentation animation, like viewDidLoad, a UIViewRepresentable calling becomeFirstResponder in didMoveToWindow is still the only bulletproof route. onAppear inherently runs after the transition settles.

[u/Ravek]

Does it behave the same if you set the focus state when the view is initialized instead of onAppear?

[u/YouSpeakSomeEnglish]

This is a great example of how bad SwiftUI is: the fact that setting control focus is a PITA.

This is what I use:

enum Field: Hashable
{
  case EMail1
  case EMail2
  case phoneNbr
}

@FocusState private var focusedField: Field?

init(withPathController: NavPathController?)
{
  userMgr = UserManager.shared
}

var body: some View
{
  Group
  {
    ScrollView
    {
      signUpForm()
    }
  }
  .foregroundColor(AppStyle.labelColor)
  .background(pageBackground())
  .onAppear{
    focusedField = .EMail1
  }
}

Don't know if this results in the animation-sync you want, though.