SwiftUI dismiss keyboard when tapping segmentedControl

Attach a custom Binding to the Picker that calls endEditing() whenever it is set:

Section(header: Text("Search Type")) {
    Picker("", selection: Binding(get: {
        self.type
    }, set: { (res) in
        self.type = res
        UIApplication.shared.endEditing()
    })) {
        Text("By Name").tag("name")
        Text("By AppId").tag("id")
    }.pickerStyle(SegmentedPickerStyle())
}

Update since iOS 13 / iPadOS 13 was released.

Since there is now support for multiple windows in one app you need to loop through the UIWindows and end editing one-by-one.

UIApplication.shared.windows.forEach { $0.endEditing(false) }

SwiftUI 2.0

Now it can be done in more elegant way, with .onChange (actually it can be attached to any view, but at TextField looks appropriate, by intention)

TextField("Placeholder", text: $searchValue)
    .keyboardType(self.type == "name" ? UIKeyboardType.alphabet : UIKeyboardType.numberPad)
    .onChange(of: type) { _ in
        UIApplication.shared.endEditing()   // << here !!
    }

SwiftUI 1.0+

There are much similar to above approaches

a) requires import Combine...

TextField("Placeholder", text: $searchValue)
    .keyboardType(self.type == "name" ? UIKeyboardType.alphabet : UIKeyboardType.numberPad)
    .onChange(of: type) { _ in
        UIApplication.shared.endEditing()
    }
    .onReceive(Just(type)) { _ in
        UIApplication.shared.endEditing()   // << here !!
    }

b) ... and not

TextField("Placeholder", text: $searchValue)
    .keyboardType(self.type == "name" ? UIKeyboardType.alphabet : UIKeyboardType.numberPad)
    .onReceive([type].publisher) { _ in
        UIApplication.shared.endEditing()   // << here !!
    }