Solution #1:

You can force the first responder to resign by sending an action to the shared application:

extension UIApplication {
    func endEditing() {
        sendAction(#selector(UIResponder.resignFirstResponder), to: nil, from: nil, for: nil)
    }
}

Now you can use this method to close the keyboard whenever you desire:

struct ContentView : View {
    @State private var name: String = ""

    var body: some View {
        VStack {
            Text("Hello (name)")
            TextField("Name...", text: self.$name) {
                // Called when the user tap the return button
                // see `onCommit` on TextField initializer.
                UIApplication.shared.endEditing()
            }
        }
    }
}

If you want to close the keyboard with a tap out, you can create a full screen white view with a tap action, that will trigger the endEditing(_:):

struct Background<Content: View>: View {
    private var content: Content

    init(@ViewBuilder content: @escaping () -> Content) {
        self.content = content()
    }

    var body: some View {
        Color.white
        .frame(width: UIScreen.main.bounds.width, height: UIScreen.main.bounds.height)
        .overlay(content)
    }
}

struct ContentView : View {
    @State private var name: String = ""

    var body: some View {
        Background {
            VStack {
                Text("Hello (self.name)")
                TextField("Name...", text: self.$name) {
                    self.endEditing()
                }
            }
        }.onTapGesture {
            self.endEditing()
        }
    }

    private func endEditing() {
        UIApplication.shared.endEditing()
    }
}

Solution #2:

After a lot of attempts I found a solution that (currently) doesn’t block any controls – adding gesture recognizer to UIWindow.

1. If you want to close keyboard only on Tap outside (without handling drags) – then it’s enough to use just UITapGestureRecognizer and just copy step 3:

2. Create custom gesture recognizer class that works with any touches:

   class AnyGestureRecognizer: UIGestureRecognizer {
       override func touchesBegan(_ touches: Set<UITouch>, with event: UIEvent) {
           if let touchedView = touches.first?.view, touchedView is UIControl {
               state = .cancelled
   
           } else if let touchedView = touches.first?.view as? UITextView, touchedView.isEditable {
               state = .cancelled
   
           } else {
               state = .began
           }
       }
   
       override func touchesEnded(_ touches: Set<UITouch>, with event: UIEvent?) {
          state = .ended
       }
   
       override func touchesCancelled(_ touches: Set<UITouch>, with event: UIEvent) {
           state = .cancelled
       }
   }
   

3. In SceneDelegate.swift in the func scene, add next code:

   let tapGesture = AnyGestureRecognizer(target: window, action:#selector(UIView.endEditing))
   tapGesture.requiresExclusiveTouchType = false
   tapGesture.cancelsTouchesInView = false
   tapGesture.delegate = self //I don't use window as delegate to minimize possible side effects
   window?.addGestureRecognizer(tapGesture)  
   

4. Implement UIGestureRecognizerDelegate to allow simultaneous touches.

   extension SceneDelegate: UIGestureRecognizerDelegate {
       func gestureRecognizer(_ gestureRecognizer: UIGestureRecognizer, shouldRecognizeSimultaneouslyWith otherGestureRecognizer: UIGestureRecognizer) -> Bool {
           return true
       }
   }
   

Now any keyboard on any view will be closed on touch or drag outside.

P.S. If you want to close only specific TextFields – then add and remove gesture recognizer to the window whenever called callback of TextField onEditingChanged

Solution #3:

SwiftUI 3 (iOS 15+)

(Done button above the keyboard)

Starting with iOS 15 we can now use @FocusState to control which field should be focused (see this answer to see more examples).

We can also add ToolbarItems directly above the keyboard.

When combined together, we can add a Done button right above the keyboard. Here is a simple demo:

struct ContentView: View {
    private enum Field: Int, CaseIterable {
        case username, password
    }

    @State private var username: String = ""
    @State private var password: String = ""

    @FocusState private var focusedField: Field?

    var body: some View {
        NavigationView {
            Form {
                TextField("Username", text: $username)
                    .focused($focusedField, equals: .username)
                SecureField("Password", text: $password)
                    .focused($focusedField, equals: .password)
            }
            .toolbar {
                ToolbarItem(placement: .keyboard) {
                    Button("Done") {
                        focusedField = nil
                    }
                }
            }
        }
    }
}

SwiftUI 2 (iOS 14+)

(Tap anywhere to hide the keyboard)

Here is an updated solution for SwiftUI 2 / iOS 14 (originally proposed here by Mikhail).

It doesn’t use the AppDelegate nor the SceneDelegate which are missing if you use the SwiftUI lifecycle:

@main
struct TestApp: App {
    var body: some Scene {
        WindowGroup {
            ContentView()
                .onAppear(perform: UIApplication.shared.addTapGestureRecognizer)
        }
    }
}

extension UIApplication {
    func addTapGestureRecognizer() {
        guard let window = windows.first else { return }
        let tapGesture = UITapGestureRecognizer(target: window, action: #selector(UIView.endEditing))
        tapGesture.requiresExclusiveTouchType = false
        tapGesture.cancelsTouchesInView = false
        tapGesture.delegate = self
        window.addGestureRecognizer(tapGesture)
    }
}

extension UIApplication: UIGestureRecognizerDelegate {
    public func gestureRecognizer(_ gestureRecognizer: UIGestureRecognizer, shouldRecognizeSimultaneouslyWith otherGestureRecognizer: UIGestureRecognizer) -> Bool {
        return true // set to `false` if you don't want to detect tap during other gestures
    }
}

If you want to detect other gestures (not only tap gestures) you can use AnyGestureRecognizer as in Mikhail’s answer:

let tapGesture = AnyGestureRecognizer(target: window, action: #selector(UIView.endEditing))

Here is an example how to detect simultaneous gestures except Long Press gestures:

extension UIApplication: UIGestureRecognizerDelegate {
    public func gestureRecognizer(_ gestureRecognizer: UIGestureRecognizer, shouldRecognizeSimultaneouslyWith otherGestureRecognizer: UIGestureRecognizer) -> Bool {
        return !otherGestureRecognizer.isKind(of: UILongPressGestureRecognizer.self)
    }
}

Solution #4:

I experienced this while using a TextField inside a NavigationView.
This is my solution for that. It will dismiss the keyboard when you start scrolling.

NavigationView {
    Form {
        Section {
            TextField("Receipt amount", text: $receiptAmount)
            .keyboardType(.decimalPad)
           }
        }
     }
     .gesture(DragGesture().onChanged{_ in UIApplication.shared.sendAction(#selector(UIResponder.resignFirstResponder), to: nil, from: nil, for: nil)})

Solution #5:

@RyanTCB’s answer is good; here are a couple of refinements that make it simpler to use and avoid a potential crash:

struct DismissingKeyboard: ViewModifier {
    func body(content: Content) -> some View {
        content
            .onTapGesture {
                let keyWindow = UIApplication.shared.connectedScenes
                        .filter({$0.activationState == .foregroundActive})
                        .map({$0 as? UIWindowScene})
                        .compactMap({$0})
                        .first?.windows
                        .filter({$0.isKeyWindow}).first
                keyWindow?.endEditing(true)                    
        }
    }
}

The ‘bug fix’ is simply that keyWindow!.endEditing(true) properly should be keyWindow?.endEditing(true) (yes, you might argue it can’t happen.)

More interesting is how you can use it. For example, suppose you have a form with multiple editable fields in it. Just wrap it like this:

Form {
    .
    .
    .
}
.modifier(DismissingKeyboard())

Now, tapping on any control that itself doesn’t present a keyboard will do the appropriate dismiss.

(Tested with beta 7)

Solution #6:

I found another way to dismiss the keyboard that doesn’t require accessing the keyWindow property; as a matter of fact the compiler gives back a warning using

UIApplication.shared.keyWindow?.endEditing(true)

‘keyWindow’ was deprecated in iOS 13.0: Should not be used for applications that support multiple scenes as it returns a key window across all connected scenes

Instead I used this code:

UIApplication.shared.sendAction(#selector(UIResponder.resignFirstResponder), to:nil, from:nil, for:nil)

Solution #7:

SwiftUI
in ‘SceneDelegate.swift’ file just add: .onTapGesture { window.endEditing(true)}

func scene(_ scene: UIScene, willConnectTo session: UISceneSession, options connectionOptions: UIScene.ConnectionOptions) {
        // Use this method to optionally configure and attach the UIWindow `window` to the provided UIWindowScene `scene`.
        // If using a storyboard, the `window` property will automatically be initialized and attached to the scene.
        // This delegate does not imply the connecting scene or session are new (see `application:configurationForConnectingSceneSession` instead).

        // Create the SwiftUI view that provides the window contents.
        let contentView = ContentView()

        // Use a UIHostingController as window root view controller.
        if let windowScene = scene as? UIWindowScene {
            let window = UIWindow(windowScene: windowScene)
            window.rootViewController = UIHostingController(
                rootView: contentView.onTapGesture { window.endEditing(true)}
            )
            self.window = window
            window.makeKeyAndVisible()
        }
    }

this is enough for each View using keyboard in your app…

Solution #8:

My solution how to hide software keyboard when users tap outside.
You need to use contentShape with onLongPressGesture to detect the entire View container. onTapGesture required to avoid blocking focus on TextField. You can use onTapGesture instead of onLongPressGesture but NavigationBar items won’t work.

extension View {
    func endEditing() {
        UIApplication.shared.sendAction(#selector(UIResponder.resignFirstResponder), to: nil, from: nil, for: nil)
    }
}

struct KeyboardAvoiderDemo: View {
    @State var text = ""
    var body: some View {
        VStack {
            TextField("Demo", text: self.$text)
        }
        .frame(maxWidth: .infinity, maxHeight: .infinity)
        .contentShape(Rectangle())
        .onTapGesture {}
        .onLongPressGesture(
            pressing: { isPressed in if isPressed { self.endEditing() } },
            perform: {})
    }
}

Solution #9:

add this modifier to the view you want to detect user taps

.onTapGesture {
            let keyWindow = UIApplication.shared.connectedScenes
                               .filter({$0.activationState == .foregroundActive})
                               .map({$0 as? UIWindowScene})
                               .compactMap({$0})
                               .first?.windows
                               .filter({$0.isKeyWindow}).first
            keyWindow!.endEditing(true)

        }

Solution #10:

I prefer using the .onLongPressGesture(minimumDuration: 0), which does not cause the keyboard to blink when another TextView is activated (side effect of .onTapGesture). The hide keyboard code can be a reusable function.

.onTapGesture(count: 2){} // UI is unresponsive without this line. Why?
.onLongPressGesture(minimumDuration: 0, maximumDistance: 0, pressing: nil, perform: hide_keyboard)

func hide_keyboard()
{
    UIApplication.shared.sendAction(#selector(UIResponder.resignFirstResponder), to: nil, from: nil, for: nil)
}

Solution #11:

Because keyWindow is deprecated.

extension View {
    func endEditing(_ force: Bool) {
        UIApplication.shared.windows.forEach { $0.endEditing(force)}
    }
}

Solution #12:

Pure SwiftUI (iOS 15)

SwiftUI in iOS 15 (Xcode 13) gained native support for programmatic focus of TextField using new @FocusState property wrapper.

To dismiss the keyboard, simply set view’s focusedField to nil. The return key will dismiss keyboard automatically (since iOS 14).

Docs: https://developer.apple.com/documentation/swiftui/focusstate/

struct MyView: View {

    enum Field: Hashable {
        case myField
    }

    @State private var text: String = ""
    @FocusState private var focusedField: Field?

    var body: some View {
        TextField("Type here", text: $text)
            .focused($focusedField, equals: .myField)

        Button("Dismiss") {
            focusedField = nil
        }
    }
}

Pure SwiftUI (iOS 14 and below)

You can completely avoid interaction with UIKit and implement it in pure SwiftUI. Just add an .id(<your id>) modifier to your TextField and change its value whenever you want to dismiss keyboard (on swipe, view tap, button action, ..).

Sample implementation:

struct MyView: View {
    @State private var text: String = ""
    @State private var textFieldId: String = UUID().uuidString

    var body: some View {
        VStack {
            TextField("Type here", text: $text)
                .id(textFieldId)

            Spacer()

            Button("Dismiss", action: { textFieldId = UUID().uuidString })
        }
    }
}

Note that I only tested it in latest Xcode 12 beta, but it should work with older versions (even Xcode 11) without any issue.

Solution #13:

Seems like the endEditing solution is the only one like @rraphael pointed out.
The cleanest example I’ve seen so far is this:

extension View {
    func endEditing(_ force: Bool) {
        UIApplication.shared.keyWindow?.endEditing(force)
    }
}

and then using it in the onCommit:

Solution #14:

Expanding on the answer by @Feldur (which was based on @RyanTCB’s), here is an even more expressive and powerful solution allowing you to dismiss keyboard on other gestures than onTapGesture, you can specify which you want in the function call.

Usage

// MARK: - View
extension RestoreAccountInputMnemonicScreen: View {
    var body: some View {
        List(viewModel.inputWords) { inputMnemonicWord in
            InputMnemonicCell(mnemonicInput: inputMnemonicWord)
        }
        .dismissKeyboard(on: [.tap, .drag])
    }
}

Or using All.gestures (just sugar for Gestures.allCases ?)

.dismissKeyboard(on: All.gestures)

Code

enum All {
    static let gestures = all(of: Gestures.self)

    private static func all<CI>(of _: CI.Type) -> CI.AllCases where CI: CaseIterable {
        return CI.allCases
    }
}

enum Gestures: Hashable, CaseIterable {
    case tap, longPress, drag, magnification, rotation
}

protocol ValueGesture: Gesture where Value: Equatable {
    func onChanged(_ action: @escaping (Value) -> Void) -> _ChangedGesture<Self>
}
extension LongPressGesture: ValueGesture {}
extension DragGesture: ValueGesture {}
extension MagnificationGesture: ValueGesture {}
extension RotationGesture: ValueGesture {}

extension Gestures {
    @discardableResult
    func apply<V>(to view: V, perform voidAction: @escaping () -> Void) -> AnyView where V: View {

        func highPrio<G>(
             gesture: G
        ) -> AnyView where G: ValueGesture {
            view.highPriorityGesture(
                gesture.onChanged { value in
                    _ = value
                    voidAction()
                }
            ).eraseToAny()
        }

        switch self {
        case .tap:
            // not `highPriorityGesture` since tapping is a common gesture, e.g. wanna allow users
            // to easily tap on a TextField in another cell in the case of a list of TextFields / Form
            return view.gesture(TapGesture().onEnded(voidAction)).eraseToAny()
        case .longPress: return highPrio(gesture: LongPressGesture())
        case .drag: return highPrio(gesture: DragGesture())
        case .magnification: return highPrio(gesture: MagnificationGesture())
        case .rotation: return highPrio(gesture: RotationGesture())
        }

    }
}

struct DismissingKeyboard: ViewModifier {

    var gestures: [Gestures] = Gestures.allCases

    dynamic func body(content: Content) -> some View {
        let action = {
            let forcing = true
            let keyWindow = UIApplication.shared.connectedScenes
                .filter({$0.activationState == .foregroundActive})
                .map({$0 as? UIWindowScene})
                .compactMap({$0})
                .first?.windows
                .filter({$0.isKeyWindow}).first
            keyWindow?.endEditing(forcing)
        }

        return gestures.reduce(content.eraseToAny()) { $1.apply(to: $0, perform: action) }
    }
}

extension View {
    dynamic func dismissKeyboard(on gestures: [Gestures] = Gestures.allCases) -> some View {
        return ModifiedContent(content: self, modifier: DismissingKeyboard(gestures: gestures))
    }
}

Word of caution

Please do note that if you use all gestures they might conflict and I did not come up with any neat solution solving that.

Solution #15:

Please check https://github.com/michaelhenry/KeyboardAvoider

Just include KeyboardAvoider {} on top of your main view and that’s all.

KeyboardAvoider {
    VStack { 
        TextField()
        TextField()
        TextField()
        TextField()
    }

}

Solution #16:

Keyboard’s Return Key

In addition to all answers about tapping outside of the textField, you may want to dismiss the keyboard when the user taps the return key on the keyboard:

define this global function:

func resignFirstResponder() {
    UIApplication.shared.sendAction(#selector(UIResponder.resignFirstResponder), to: nil, from: nil, for: nil)
}

And add use in onCommit argument it:

TextField("title", text: $text, onCommit:  {
    resignFirstResponder()
})

Benefits

• You can call it from anywhere
• It’s not dependent on UIKit or SwiftUI (can be used in mac apps)
• It works even in iOS 13

Demo

Solution #17:

This method allows you to hide the keyboard on spacers!

First add this function (Credit Given To: Casper Zandbergen, from SwiftUI can’t tap in Spacer of HStack)

extension Spacer {
    public func onTapGesture(count: Int = 1, perform action: @escaping () -> Void) -> some View {
        ZStack {
            Color.black.opacity(0.001).onTapGesture(count: count, perform: action)
            self
        }
    }
}

Next add the following 2 functions (Credit Given To: rraphael, from this question)

extension UIApplication {
    func endEditing() {
        sendAction(#selector(UIResponder.resignFirstResponder), to: nil, from: nil, for: nil)
    }
}

The function below would be added to your View class, just refer to the top answer here from rraphael for more details.

private func endEditing() {
   UIApplication.shared.endEditing()
}

Finally, you can now simply call…

Spacer().onTapGesture {
    self.endEditing()
}

This will make any spacer area close the keyboard now. No need for a big white background view anymore!

You could hypothetically apply this technique of extension to any controls you need to support TapGestures that do not currently do so and call the onTapGesture function in combination with self.endEditing() to close the keyboard in any situation you desire.

Solution #18:

Based on @Sajjon’s answer, here is a solution allowing you to dismiss keyboard on tap, long press, drag, magnification and rotation gestures according to your choice.

This solution is working in XCode 11.4

Usage to get the behavior asked by @IMHiteshSurani

struct MyView: View {
    @State var myText = ""

    var body: some View {
        VStack {
            DismissingKeyboardSpacer()

            HStack {
                TextField("My Text", text: $myText)

                Button("Return", action: {})
                    .dismissKeyboard(on: [.longPress])
            }

            DismissingKeyboardSpacer()
        }
    }
}

struct DismissingKeyboardSpacer: View {
    var body: some View {
        ZStack {
            Color.black.opacity(0.0001)

            Spacer()
        }
        .dismissKeyboard(on: Gestures.allCases)
    }
}

Code

enum All {
    static let gestures = all(of: Gestures.self)

    private static func all<CI>(of _: CI.Type) -> CI.AllCases where CI: CaseIterable {
        return CI.allCases
    }
}

enum Gestures: Hashable, CaseIterable {
    case tap, longPress, drag, magnification, rotation
}

protocol ValueGesture: Gesture where Value: Equatable {
    func onChanged(_ action: @escaping (Value) -> Void) -> _ChangedGesture<Self>
}

extension LongPressGesture: ValueGesture {}
extension DragGesture: ValueGesture {}
extension MagnificationGesture: ValueGesture {}
extension RotationGesture: ValueGesture {}

extension Gestures {
    @discardableResult
    func apply<V>(to view: V, perform voidAction: @escaping () -> Void) -> AnyView where V: View {

        func highPrio<G>(gesture: G) -> AnyView where G: ValueGesture {
            AnyView(view.highPriorityGesture(
                gesture.onChanged { _ in
                    voidAction()
                }
            ))
        }

        switch self {
        case .tap:
            return AnyView(view.gesture(TapGesture().onEnded(voidAction)))
        case .longPress:
            return highPrio(gesture: LongPressGesture())
        case .drag:
            return highPrio(gesture: DragGesture())
        case .magnification:
            return highPrio(gesture: MagnificationGesture())
        case .rotation:
            return highPrio(gesture: RotationGesture())
        }
    }
}

struct DismissingKeyboard: ViewModifier {
    var gestures: [Gestures] = Gestures.allCases

    dynamic func body(content: Content) -> some View {
        let action = {
            let forcing = true
            let keyWindow = UIApplication.shared.connectedScenes
                .filter({$0.activationState == .foregroundActive})
                .map({$0 as? UIWindowScene})
                .compactMap({$0})
                .first?.windows
                .filter({$0.isKeyWindow}).first
            keyWindow?.endEditing(forcing)
        }

        return gestures.reduce(AnyView(content)) { $1.apply(to: $0, perform: action) }
    }
}

extension View {
    dynamic func dismissKeyboard(on gestures: [Gestures] = Gestures.allCases) -> some View {
        return ModifiedContent(content: self, modifier: DismissingKeyboard(gestures: gestures))
    }
}

Solution #19:

Expanding the answer by josefdolezal above, you can hide keyboard when user taps anywhere outside the textfield like below:

struct SwiftUIView: View {
        @State private var textFieldId: String = UUID().uuidString // To hidekeyboard when tapped outside textFields
        @State var fieldValue = ""
        var body: some View {
            VStack {
                TextField("placeholder", text: $fieldValue)
                    .id(textFieldId)
                    .onTapGesture {} // So that outer tap gesture has no effect on field

                // any more views

            }
            .onTapGesture { // whenever tapped within VStack
                textFieldId = UUID().uuidString 
               //^ this will remake the textfields hence loosing keyboard focus!
            }
        }
    }

Solution #20:

So far above options did not work for me, because I have Form and inside buttons, links, picker …

I create below code that is working, with help from above examples.

import Combine
import SwiftUI

private class KeyboardListener: ObservableObject {
    @Published var keyabordIsShowing: Bool = false
    var cancellable = Set<AnyCancellable>()

    init() {
        NotificationCenter.default
            .publisher(for: UIResponder.keyboardWillShowNotification)
            .sink { [weak self ] _ in
                self?.keyabordIsShowing = true
            }
            .store(in: &cancellable)

       NotificationCenter.default
            .publisher(for: UIResponder.keyboardWillHideNotification)
            .sink { [weak self ] _ in
                self?.keyabordIsShowing = false
            }
            .store(in: &cancellable)
    }
}

private struct DismissingKeyboard: ViewModifier {
    @ObservedObject var keyboardListener = KeyboardListener()

    fileprivate func body(content: Content) -> some View {
        ZStack {
            content
            Rectangle()
                .background(Color.clear)
                .opacity(keyboardListener.keyabordIsShowing ? 0.01 : 0)
                .frame(width: UIScreen.main.bounds.width, height: UIScreen.main.bounds.height)
                .onTapGesture {
                    let keyWindow = UIApplication.shared.connectedScenes
                        .filter({ $0.activationState == .foregroundActive })
                        .map({ $0 as? UIWindowScene })
                        .compactMap({ $0 })
                        .first?.windows
                        .filter({ $0.isKeyWindow }).first
                    keyWindow?.endEditing(true)
                }
        }
    }
}

extension View {
    func dismissingKeyboard() -> some View {
        ModifiedContent(content: self, modifier: DismissingKeyboard())
    }
}

Usage:

 var body: some View {
        NavigationView {
            Form {
                picker
                button
                textfield
                text
            }
            .dismissingKeyboard()

Solution #21:

Something I found that works very nice is

 extension UIApplication {
    func endEditing() {
        sendAction(#selector(UIResponder.resignFirstResponder), to: nil, from: nil, for: nil)
    }
}

Then add to the view struct:

 private func endEditing() {
    UIApplication.shared.endEditing()
}

Then

struct YourView: View {
    var body: some View {
       ParentView {
           //...
       }.contentShape(Rectangle()) //<---- This is key!
        .onTapGesture {endEditing()} 
     }
 }
    

Solution #22:

Simple solution for clicking “outside” that worked for me:

First provide a ZStack before all views. In it, put a background (with the color of your choosing) and supply a tap Gesture. In the gesture call, invoke the ‘sendAction’ we’ve seen above:

import SwiftUI

struct MyView: View {
    private var myBackgroundColor = Color.red
    @State var text = "text..."

var body: some View {
    ZStack {
        self.myBackgroundColor.edgesIgnoringSafeArea(.all)
            .onTapGesture(count: 1) {
                UIApplication.shared.sendAction(#selector(UIResponder.resignFirstResponder), to: nil, from: nil, for: nil)
        }
        TextField("", text: $text)
            .textFieldStyle(RoundedBorderTextFieldStyle())
            .padding()
    }
  }
}
extension UIApplication {
   func endEditing() {
       sendAction(#selector(UIResponder.resignFirstResponder), to: nil, from: nil, for: nil)
  }
}

Solution #23:

A cleaner SwiftUI-native way to dismiss the keyboard via tap without blocking any complicated forms or whatnot… credit to @user3441734 for flagging GestureMask as a clean approach.

1. Monitor UIWindow.keyboardWillShowNotification / willHide

2. Pass the current keyboard state via an EnvironmentKey set at the/a root view

Tested for iOS 14.5.

Attach dismiss gesture to the form

Form { }
    .dismissKeyboardOnTap()

Setup monitor in root view

// Root view
    .environment(.keyboardIsShown, keyboardIsShown)
    .onDisappear { dismantleKeyboarMonitors() }
    .onAppear { setupKeyboardMonitors() }

// Monitors

    @State private var keyboardIsShown = false
    @State private var keyboardHideMonitor: AnyCancellable? = nil
    @State private var keyboardShownMonitor: AnyCancellable? = nil
    
    func setupKeyboardMonitors() {
        keyboardShownMonitor = NotificationCenter.default
            .publisher(for: UIWindow.keyboardWillShowNotification)
            .sink { _ in if !keyboardIsShown { keyboardIsShown = true } }
        
        keyboardHideMonitor = NotificationCenter.default
            .publisher(for: UIWindow.keyboardWillHideNotification)
            .sink { _ in if keyboardIsShown { keyboardIsShown = false } }
    }
    
    func dismantleKeyboarMonitors() {
        keyboardHideMonitor?.cancel()
        keyboardShownMonitor?.cancel()
    }

SwiftUI Gesture + Sugar

struct HideKeyboardGestureModifier: ViewModifier {
    @Environment(.keyboardIsShown) var keyboardIsShown
    
    func body(content: Content) -> some View {
        content
            .gesture(TapGesture().onEnded {
                UIApplication.shared.resignCurrentResponder()
            }, including: keyboardIsShown ? .all : .none)
    }
}

extension UIApplication {
    func resignCurrentResponder() {
        sendAction(#selector(UIResponder.resignFirstResponder),
                   to: nil, from: nil, for: nil)
    }
}

extension View {

    /// Assigns a tap gesture that dismisses the first responder only when the keyboard is visible to the KeyboardIsShown EnvironmentKey
    func dismissKeyboardOnTap() -> some View {
        modifier(HideKeyboardGestureModifier())
    }
    
    /// Shortcut to close in a function call
    func resignCurrentResponder() {
        UIApplication.shared.resignCurrentResponder()
    }
}

EnvironmentKey

extension EnvironmentValues {
    var keyboardIsShown: Bool {
        get { return self[KeyboardIsShownEVK] }
        set { self[KeyboardIsShownEVK] = newValue }
    }
}

private struct KeyboardIsShownEVK: EnvironmentKey {
    static let defaultValue: Bool = false
}

Solution #24:

True SwiftUI Solution

@State var dismissKeyboardToggle = false
var body: some View {
    if dismissKeyboardToggle {
        textfield
    } else {
        textfield
    }
    
    Button("Hide Keyboard") {
        dismissKeyboardToggle.toggle()
    }                   
}

this will work flawlessly

Solution #25:

SwiftUI released on June/2020 with Xcode 12 and iOS 14 adds hideKeyboardOnTap() modifier. This should solve your case number 2.
The solution for your case number 1 comes for free with Xcode 12 and iOS 14: the default keyboard for TextField hides automatically when the Return button is pressed.