SwiftUI's @FocusState cannot show a sheet with the system keyboard in a single animation as UIKit can. focusOnAppear is a SwiftUI view modifier that enables this functionality.
focusOnAppear.mp4
When you apply focusOnAppear to a SwiftUI's TextField or SecureField, the modifier adds a hidden UITextField behind the SwiftUI view. When the view appears on the screen, the hidden UITextField calls becomeFirstResponder to gain focus before the SwiftUI view actually appears on the screen, enabling the SwiftUI view to appear with the system keyboard in a single animation.
// Simply want to focus on appear
TextField("Text", text: $text)
.focusOnAppear()
// Focus on appear, but also want to control focus state
TextField("Text", text: $text)
.focusOnAppear($isFocused)
TextField("Text", text: $text)
.focusOnAppear($field, equals: .email)
// When using SecureField
SecureField("Password", text: $password)
.focusOnAppear(config: .init(isSecure: true))Because focusOnAppear uses the hidden UITextField then switches focus to the SwiftUI View, you want to match the keyboard type, return key type, and whether the text input is secure or not, so the keyboard doesn't change when the view appears.
This modifier only works when the view is presented in a sheet. If the view is presented in a NavigationStack, it still works, but you'll see the system keyboard appears in a glitchy animation.
focusOnAppear is available under the MIT license. See LICENSE for more information.