I have this...
func makeUIView(context: Context) -> UIScrollView {
let control = UIScrollView()
control.addSubview(UIHostingController(rootView: preview).view)
return control
}
If I put my preview view outside of my custom scroll view then I can see it. But when I add it as a subview of a UIScrollView then I can't see anything.
Have I added it correctly?
Here is the complete code for the scroll view, which I got from here.
import SwiftUI
import Foundation
struct LegacyScrollView : UIViewRepresentable {
var preview: AnyView
init(preview: AnyView) {
self.preview = preview
}
func makeCoordinator() -> Coordinator {
Coordinator(self)
}
func makeUIView(context: Context) -> UIScrollView {
let control = UIScrollView()
control.addSubview(UIHostingController(rootView: preview).view)
return control
}
func updateUIView(_ uiView: UIScrollView, context: Context) {
}
class Coordinator: NSObject {
var control: LegacyScrollView
init(_ control: LegacyScrollView) {
self.control = control
}
#objc func handleRefreshControl(sender: UIRefreshControl) {
sender.endRefreshing()
}
}
}
Related
I want build a struct that it takes a UI type as input and it present that UI in SwiftUI, for example I have this down codes for UILabel and UIButton, I want make a generic one to free me from making an individual struct for each UI from UIKit:
struct UILabelViewRepresentable: UIViewRepresentable {
let configuration: (UILabel) -> ()
func makeUIView(context: Context) -> UILabel {
return UILabel()
}
func updateUIView(_ uiView: UILabel, context: Context) {
configuration(uiView)
}
}
struct UIButtonViewRepresentable: UIViewRepresentable {
let configuration: (UIButton) -> ()
func makeUIView(context: Context) -> UIButton {
return UIButton()
}
func updateUIView(_ uiView: UIButton, context: Context) {
configuration(uiView)
}
}
Here what I tried so far:
struct GenericUIViewRepresentable<UIViewType: UIView>: UIViewRepresentable {
let uiViewType: UIViewType
let configuration: (UIViewType) -> ()
func makeUIView(context: Context) -> UIViewType {
return uiViewType
}
func updateUIView(_ uiView: UIViewType, context: Context) {
configuration(uiView)
}
}
it makes an error when I want use it:
Cannot convert value of type 'UILabel.Type' to expected argument type 'UIView'
So I know about the error, I want make my code works and it makes me free to type all UIKit UI that I want.
use case:
struct ContentView: View {
var body: some View {
GenericUIViewRepresentable(uiViewType: UILabel, configuration: { label in
label.text = "Hello, World!"
})
}
}
You want to pass in the UIView type, not just a UIView instance. This means you want to do UIViewType.Type rather than UIViewType.
Code:
struct GenericUIViewRepresentable<UIView: UIKit.UIView>: UIViewRepresentable {
let uiViewType: UIView.Type
let configuration: (UIView) -> ()
func makeUIView(context: Context) -> UIView {
uiViewType.init()
}
func updateUIView(_ uiView: UIView, context: Context) {
configuration(uiView)
}
}
Usage:
struct ContentView: View {
var body: some View {
VStack {
Text("Hello world!")
GenericUIViewRepresentable(uiViewType: UILabel.self) { label in
label.text = "Other text!"
}
}
}
}
Here on swift.org is where you can learn more about metatype types.
I have been writing a UIViewRepresentable and noticing some curios effects in regards to a binding I'm passing into the view.
When I read the bindings value in the coordinator through the saved UIViewRepresentable the value is always the value that it was initialized with. Trying to update the same binding however triggers an update in the surrounding UI.
This is code produces this behavior:
struct NativeTextView: UIViewRepresentable {
#Binding var text: String
func makeUIView(context: Context) -> UITextField {
let view = UITextField()
view.borderStyle = .roundedRect
view.addTarget(
context.coordinator,
action: #selector(Coordinator.updateText(sender:)),
for: .editingChanged
)
return view
}
func updateUIView(_ uiView: UITextField, context: Context) {
context.coordinator.updateUI(uiView)
}
func makeCoordinator() -> Coordinator {
Coordinator(_text)
}
class Coordinator: NSObject {
#Binding var text: String
init(_ text: Binding<String>){
_text = text
}
#objc func updateText(sender: UITextField){
text=sender.text!
}
func updateUI(_ uiView: UITextField) {
uiView.text = text
}
}
}
If I hover give my updateUI method a NativeTextView parameter, and use the .text field of it through the parameter, I read the correct value and the UI works correctly:
struct NativeTextView: UIViewRepresentable {
#Binding var text: String
func makeUIView(context: Context) -> UITextField {
let view = UITextField()
view.borderStyle = .roundedRect
view.addTarget(
context.coordinator,
action: #selector(Coordinator.updateText(sender:)),
for: .editingChanged
)
return view
}
func updateUIView(_ uiView: UITextField, context: Context) {
context.coordinator.updateUI(uiView, view: self)
}
func makeCoordinator() -> Coordinator {
Coordinator(self)
}
class Coordinator: NSObject {
var myView: NativeTextView
init(_ view: NativeTextView){
self.myView=view
}
#objc func updateText(sender: UITextField){
myView.text=sender.text!
}
func updateUI(_ uiView: UITextField, view: NativeTextView) {
uiView.text = view.text
}
}
}
It seems that the binding retains the ability to write to the outside #State variable but does not manage to access the current states value correctly. I'm guessing that this has something to do with the recreation of the NativeTextView view when SwiftUI notices an update of the #State, but I have not been able to find any documentation that would explain this behavior.
Does anyone know why this happens?
PS: for completeness this is my ContentViews body:
ZStack {
Color.red
VStack {
Text(test)
.padding()
.onTapGesture() {
test = "Bla"
}
NativeTextView(text: $test)
}
}
How can I extend camera scanning view to safa area while using VNDocumentCameraViewController in UIViewControllerRepresentable?
here is the code
struct ScanDocumentView: UIViewControllerRepresentable {
func makeCoordinator() -> Coordinator {
Coordinator(recognizedText: $recognizedText, parent: self)
}
func makeUIViewController(context: Context) -> VNDocumentCameraViewController {
let documentViewController = VNDocumentCameraViewController()
documentViewController.delegate = context.coordinator
return documentViewController
}
func updateUIViewController(_ uiViewController: VNDocumentCameraViewController, context: Context) {
// nothing to do here
}
}
and here is it's behavior where the bottom safe area is blank
Problem solved! just add
.ignoresSafeArea()
under
ScanDocumentView()
and that's all
I am working with SwiftUI 1.0.
I have created a search bar for SwiftUI as the following:
import SwiftUI
struct Searchbar: NSViewRepresentable {
class Coordinator: NSObject, NSSearchFieldDelegate {
var parent: Searchbar
init(_ parent: Searchbar) {
self.parent = parent
}
func controlTextDidChange(_ notification: Notification) {
guard let searchField = notification.object as? NSSearchField else {
log.error("Unexpected control in update notification", source: .ui)
return
}
self.parent.search = searchField.stringValue
}
}
#Binding var search: String
func makeNSView(context: Context) -> NSSearchField {
let searchfield = NSSearchField(frame: .zero)
return searchfield
}
func changeSearchFieldItem(searchfield: NSSearchField, sender: AnyObject) -> NSSearchField {
//Based on the Menu item selection in the search field the placeholder string is set
(searchfield.cell as? NSSearchFieldCell)?.placeholderString = sender.title
return searchfield
}
func updateNSView(_ searchField: NSSearchField, context: Context) {
searchField.stringValue = search
searchField.delegate = context.coordinator
}
func makeCoordinator() -> Coordinator {
return Coordinator(self)
}
}
This is working fine so far when using it in my View:
Searchbar(search: $searchText)
I am wondering if the height of the NSSearchField can be changed to have a view similar to what is seen in the Maps.app:
Update: You can also set the controlSize to .large if you’re on Big Sur.
https://developer.apple.com/documentation/appkit/nscontrol/controlsize/large
You can add a height constraint:
func makeNSView(context: Context) -> NSSearchField {
let searchfield = NSSearchField(frame: .zero)
searchfield.translatesAutoresizingMaskIntoConstraints = false
searchfield.heightAnchor.constraint(greaterThanOrEqualToConstant: 40).isActive = true
return searchfield
}
…which works in macOS 11.1 Big Sur. Unfortunately the Focus ring does not adapt its height. You could hide it like this:
searchTextField.focusRingType = .none
… but that does not seem desirable in most situations.
How can I set content mode as fit for a custom UIImageView wrapped in SwiftU?
struct CustomView: UIViewRepresentable {
func makeUIView(context: Context) -> UIImageView {
CustomUIImage()
}
func updateUIView(_ uiView: UIImageView, context: Context) {
}
}
struct ContentView: View {
var body: some View {
CustomView()
}
}
In the code above, CustomUIImage is a subclass of UIImageView from UIKit. It's wrapped in UIViewRepresentable to integrate it with the SwiftUI framework. Calling CustomView().aspectRatio(contentMode: .fit) didn't work in this case
Here is possible approach
struct CustomView: UIViewRepresentable {
private let imageView = CustomUIImage()
init(contentMode: UIView.ContentMode = .center) {
imageView.contentMode = contentMode
}
func makeUIView(context: Context) -> UIImageView {
imageView
}
func updateUIView(_ uiView: UIImageView, context: Context) {
}
}
struct ContentView: View {
var body: some View {
CustomView(contentMode: .scaleAspectFit)
}
}