I simply have such protocols:
protocol Containerable {
var containerView: UIView { get }
var containerController: UIViewController { get }
var oldViewController: UIViewController? { get set }
}
protocol ContainerRoutable: class {
func load(controller: UIViewController, into context: inout Containerable)
}
extension ContainerRoutable {
func load(controller: UIViewController, into context: inout Containerable) {
context.oldViewController?.willMove(toParent: nil)
context.oldViewController?.view.removeFromSuperview()
context.oldViewController?.removeFromParent()
controller.view.frame = context.containerView.bounds
context.containerController.addChild(controller)
context.containerView.addSubview(controller.view)
context.oldViewController = controller
controller.didMove(toParent: context.containerController)
}
func loadDashboard(into context: inout Containerable) {
let controller = assembler.resolve(DashboardViewController.self)!
load(controller: controller, into: &context)
}
}
and now on the tap action I need to use it:
mainView.dashboardButton.rx.tap.bind { [weak self] in
self?.mainView.activateDashboardMenuItem()
if var a = self as? Containerable { //warning: Conditional downcast from 'TabBarController?' to 'Containerable' is equivalent to an implicit conversion to an optional 'Containerable'
self?.router.loadDashboard(into: &a)
}
}.disposed(by: bag)
What is self?
class TabBarController: UIViewController, Containerable {
private let mainView: TabBarView
let router: TabBarRoutable
private let bag = DisposeBag()
var oldViewController: UIViewController?
var containerController: UIViewController {
return self
}
var containerView: UIView {
return mainView.containerView
}
}
How to remove the following warning?
Conditional downcast from 'TabBarController?' to 'Containerable' is equivalent to an implicit conversion to an optional 'Containerable'
Update the if-condition as,
if var a: Containerable = self {
self?.router.loadDashboard(into: &a)
}
Related
I am implementing a UIViewController with a ViewModel as an argument passed to the UIViewController, but I can't seem to make the delegate functions to work, what is the correct way of doing this?
CartView.swift
struct PaymentWrapper: UIViewControllerRepresentable {
typealias UIViewControllerType = CustomUIPaymentViewController
#ObservedObject var viewModel: CartViewModel
var vc: CustomUIPaymentViewController?
var foo: (String) -> Void
public init(viewModel: CartViewModel) {
self.viewModel = viewModel
self.vc = CustomUIPaymentViewController.init(token: self.viewModel.mtToken)
}
func makeUIViewController(context: Context) -> CustomUIPaymentViewController {
return vc!
}
func updateUIViewController(_ uiViewController: CustomUIPaymentViewController, context: Context) {
// code
}
func makeCoordinator() -> Coordinator {
Coordinator(vc: vc!, foo: foo)
}
class Coordinator: NSObject, CustomUIPaymentViewControllerDelegate, CustomUINavigationControllerDelegate {
var foo: (String) -> Void
init(vc: CustomUIPaymentViewController, foo: #escaping (String) -> Void) {
self.foo = foo
super.init()
vc.delegate = self
}
func paymentViewController(_ viewController: CustomUIPaymentViewController!, paymentFailed error: Error!) {
foo("FAILED")
}
func paymentViewController(_ viewController: CustomUIPaymentViewController!, paymentPending result: TransactionResult!) {
foo("PENDING")
}
func paymentViewController(_ viewController: CustomUIPaymentViewController!, paymentSuccess result: TransactionResult!) {
foo("SUCCESS")
}
func paymentViewController_paymentCanceled(_ viewController: CustomUIPaymentViewController!) {
foo("CANCEL")
}
//This delegate methods is added on ios sdk v1.16.4 to handle the new3ds flow
func paymentViewController(_ viewController: CustomUIPaymentViewController!, paymentDeny result: TransactionResult!) {
}
}
}
struct CartView: View {
#ObservedObject var viewModel = CartViewModel()
var body: some View {
VStack {
Header(title: "Cart", back: false)
}
.sheet(isPresented: $viewModel.showPayment) {
PaymentWrapper(viewModel: self.viewModel) { data in
print(data)
// This returns error "Extra trailing closure passed in call"
}
}
}
}
How do I get the delegate to work? what am I doing wrong? Thank you in advance.
Ideally, I want to create a BaseViewController class that takes in a protocol type (of a delegate) and have a weak variable as the delegate. Something like this:
class BaseViewController<Delegate: AnyObject> {
weak var delegate: Delegate?
init(delegate: Delegate) {
self.delegate = delegate
super.init(...)
}
}
And then inherit from a view controller like so:
protocol MyDelegate: AnyObject {
func funcA()
func funcB()
}
class SomeViewController: BaseViewController<MyDelegate> {
func doSomething() {
delegate?.funcA()
}
}
This doesn't work as the compiler complains:
'BaseViewController' requires that 'MyDelegate' be a class type
How can I work this around to achieve what I need?
Thanks in advance :)
Thats because in swift protocols doesn't confirm to them selves, you can't use "MyProtocol" as concrete type confirming to protocol "MyDelegate"
What you can rather do is
protocol MyDelegate: AnyObject {
func funcA()
func funcB()
}
class BaseViewController<Delegate: MyDelegate> {
weak var delegate: Delegate?
init(delegate: Delegate) {
self.delegate = delegate
super.init(...)
//keeping OPs code as is
}
}
class SomeOtherDelegateClass: MyDelegate {
func funcA() {
//some code here
}
func funcB() {
//some code here
}
}
class SomeViewController: BaseViewController<SomeOtherDelegateClass> {
func doSomething() {
self.delegate?.funcA()
}
}
EDIT 1:
As OP mentioned in comment, he is trying to introduce a generic property in BaseViewController that will simply hold a weak reference to any instance whose class is decided/declared by Child classes of BaseViewController using generics, I am simplifying the above answer a bit
Try this
protocol MyDelegate {
func funcA()
func funcB()
}
class BaseViewController<Delegate> where Delegate: AnyObject {
weak var delegate: Delegate?
init(delegate: Delegate) {
self.delegate = delegate
super.init(...)
//keeping OPs code as is
}
}
class SomeOtherDelegateClass: MyDelegate {
func funcA() {
//some code here
}
func funcB() {
//some code here
}
}
class SomeViewController: BaseViewController<SomeOtherDelegateClass> {
func doSomething() {
self.delegate?.funcA()
}
}
protocol MyDelegate2 {
func funcABCD()
}
class SomeOtherDelegateClass2: MyDelegate2 {
func funcABCD() {
//some code here
}
}
class SomeViewController2: BaseViewController<SomeOtherDelegateClass2> {
func doSomething() {
self.delegate?.funcABCD()
}
}
TBH, I really dont see much of benefit of this design! Probably you need to revisit the code structure and see if you can come up with better code structure :)
You should set your delegate as a constraint for the generic type T in BaseViewController:
protocol MyDelegate: AnyObject {
func funcA()
func funcB()
}
class Delegated1: MyDelegate {
func funcA() { print("A1") }
func funcB() {}
}
class Delegated2: MyDelegate {
func funcA() { print("A2") }
func funcB() {}
}
class BaseViewController<T: MyDelegate>: UIViewController {
var delegate: T?
func doSomething() {
delegate?.funcA()
}
}
class SomeViewController1: BaseViewController<Delegated1> {}
class SomeViewController2: BaseViewController<Delegated2> {}
class TestClass {
let viewController1: SomeViewController1 = {
let viewController = SomeViewController1(nibName: nil, bundle: nil)
viewController.delegate = .init()
return viewController
}()
let viewController2: SomeViewController2 = {
let viewController = SomeViewController2(nibName: nil, bundle: nil)
viewController.delegate = .init()
return viewController
}()
// prints:
// A1
// A2
func myFunc() {
viewController1.doSomething()
viewController2.doSomething()
}
}
I am using delegates to get a string value from my modal. When the modal closes I am trying to update Label text using that string. However, I am getting error: Unexpectedly found nil while implicitly unwrapping an Optional value: file. I am not sure how to fix this. I think it's happening because the view is not yet active.
import Cocoa
class ViewControllerA: NSViewController, SomeDelegate {
#IBOutlet weak var msgLabel: NSTextField!
var s: String = "";
override var representedObject: Any? {
didSet {
// Update the view, if already loaded.
}
}
func setDetails(s: String) {
self.user = s;
print("Notified", self.s) // <-- prints: Notified hello again
msgLabel.stringValue = self.s <-- DOESN'T WORK
}
func showModal() -> Void {
msgLabel.stringValue = "hello" // <--- WORKS
let cbvc: NSViewController = {
return self.storyboard!.instantiateController(withIdentifier: "ControllerBVC")
as! NSViewController
}()
self.presentAsModalWindow(cbvc);
}
#IBAction func onBtn(_ sender: Any) {
self.showModal();
}
}
protocol SomeDelegate {
func setDetails(s: String)
}
class ViewControllerB: NSViewController {
#IBOutlet weak var textF: NSTextField!
var delegate: SomeDelegate?
override func viewDidLoad() {
super.viewDidLoad()
// Do view setup here.
let vc = ViewControllerA()
self.delegate = vc
}
#IBAction func onBtn(_ sender: Any) {
DispatchQueue.main.async {
self.delegate?.setDetails(s: self.textF.stringValue)
self.dismiss("ControllerAVC")
}
}
}
You have a number of problems.
In ViewControllerB.viewDidLoad you are assigning a new instance of ViewControllerA to the delegate property. Don't do that. Your viewDidLoad method should look like this:
override func viewDidLoad() {
super.viewDidLoad()
}
In the showModal method ViewControllerA should assign itself as the delegate on ViewControllerB before ViewControllerB it is presented.
func showModal() -> Void {
let cbvc: NSViewController = {
let vc = self.storyboard!.instantiateController(withIdentifier: "ControllerBVC")
as! ViewControllerB
vc.delegate = self
return vc
}()
self.presentAsModalWindow(cbvc);
}
In the setDetails method just assign the string to your text field directly:
func setDetails(s: String) {
msgLabel.stringValue = s
}
I would like to understand what would be the best way to implement a delegate out UIViewController class
How can I manage the delegate using controller: UIViewController parameter of my function in AuthManager?
These are the two classes I'm working with .. I show you small examples to make you understand
class StartController: UIViewController {
#objc private func presentAuthFacebookController() {
AuthManager.signInWithFacebook(controller: self)
}
}
class AuthManager {
static func signInWithFacebook(controller: UIViewController) {
let loginManager = LoginManager()
loginManager.logIn(permissions: [.publicProfile, .email], viewController: controller) { (result) in
switch result {
case .cancelled : print("\n AuthFacebook: operazione annullata dall'utente \n")
case .failed(let error) : print("\n AuthFacebook: \(error) \n")
case .success(granted: _, declined: let declinedPermission, token: _):
let authVC = ExistingEmailController()
authVC.delegate = // ?????? (controller)
UIApplication.shared.windows.first?.rootViewController?.present(authVC, animated: true, completion: nil)
}
}
}
}
I personally don't think StartController should know about/conform to ExistingEmailControllerDelegate. But if you really want, you can declare controller as a composition type:
static func signInWithFacebook(controller: UIViewController & ExistingEmailControllerDelegate) {
...
authVC.delegate = controller
In my opinion, the whole point of having a AuthManager is to create a layer of abstraction on top of ExistingEmailController, and to encapsulate the logic of authentication. Therefore, StartController shouldn't know, or care, about ExistingEmailControllerDelegate. It only knows about AuthManager.
AuthManager should be the delegate of ExistingEmailController, which implies that signInWithFacebook should not be static, and AuthManager can have an AuthManagerDelegate that StartController conforms to:
class AuthManager : ExistingEmailControllerDelegate {
weak var delegate: AuthManagerDelegate?
func signInWithFacebook(controller: UIViewController) {
...
let authVC = ExistingEmailController()
authVC.delegate = self
UIApplication.shared.windows.first?.rootViewController?.present(authVC, animated: true, completion: nil)
}
func someMethodFromExistingEmailControllerDelegate() {
delegate?.someMethod() // delegating it self.delegate, which StartController conforms to
}
}
protocol AuthManagerDelegate : class {
func someMethod()
}
class StartController: UIViewController, AuthManagerDelegate {
var authManager: AuthManager!
override func viewDidLoad() {
authManager = AuthManager()
authManager.delegate = self
}
#objc private func presentAuthFacebookController() {
authManager.signInWithFacebook(controller: self)
}
func someMethod() {
// write here the code that you would have written in someMethodFromExistingEmailControllerDelegate
}
}
I have the following ViewController:
class PageContentViewController: UIViewController {
var pageIndex: Int
}
How would I access pageIndex from another ViewController?
I need to access pageIndex in this function:
func pageViewController(pageViewController: UIPageViewController!, viewControllerBeforeViewController viewController: UIViewController!) -> UIViewController! {
//var index: Int
//index = ?
NSUInteger index = ((PageContentViewController*) viewController).pageIndex; // in Swift?
if ((index == 0) || (index == NSNotFound)) {
return nil;
}
index--;
return [self viewControllerAtIndex:index]; // in Swift?
}
Everything by default in swift is public, and thus if you declare something like this:
class SomeViewController: UIViewController {
var someVariable: SomeType = someValue
init(nibName nibNameOrNil: String?, bundle nibBundleOrNil: NSBundle?) {
super.init(nibName: nibNameOrNil, bundle: nibBundleOrNil)
}
}
You can access it as long as you have an instance of it:
var myCustomViewController: SomeViewController = SomeViewController(nibName: nil, bundle: nil)
var getThatValue = myCustomViewController.someVariable
ViewController1.swift
class ViewController1: UIViewController {
struct GlobalVariable{
static var myString = String()
}
}
ViewController2.swift
class ViewController2: UIViewController
{
print(ViewController1.GlobalVariable.myString)
}
I solved this way . .
class StaticLinker
{
static var viewController : PageContentViewController? = nil
}
class PageContentViewController: UIViewController
{
var pageIndex: Int
StaticLinker.viewController = self
}
class AnotherClass
{
StaticLinker.viewController.pageIndex = 100
}
Here's my attempt to convert that code to swift:
func pageViewController(pageViewController: UIPageViewController!, viewControllerBeforeViewController viewController: UIViewController!) -> UIViewController! {
var pageController = viewController as PageContentViewController
var index: Int? = pageController.pageIndex
if var idx: Int = index{
if idx == 0{
return nil
}
else{
idx--
return viewControllerAtIndex(idx)
}
}
else{
return nil
}
}
class PageContentViewController: UIViewController {
var pageIndex: Int?
}
I was facing the same problem when i have to use token in every other class, the solution is pretty simple, What i did was
var access = LoginViewController()
token = access.token
but the problem it encountered was: Using the default value for token.
so i made that variable static and used this in view did load.
var token : String = ""
var access = LoginViewController.self
token = access.token
class color: UIViewController {
var blue:Int = 90
}
access it from other class (make sure to call the variable within a function otherwise you gonna get error )
class ViewController: UIViewController{
var example:color = color()
override func viewDidLoad() {
super.viewDidLoad()
// call it here
print(example.blue)
}
}
class firstViewController: UIViewController{
var variableName: variableType = variableValue
}
You can access this variable in the secondViewController by creating an instance of firstViewController()
class secondViewController: UIViewController{
var newVariableName = firstViewController()
}
later on use the newVariableName to access the value of the variableName
newVariableName.variableName