Hi I created a simple framework with a delegate to return back a value to my main app.
Steps I did:
Created a framework in Xcode
Created a protocol as public
Imported my framework in main app project and integrated my protocol successfully
But not able to grab the value from framework
In framework
public protocol MyDataSendingDelegateProtocol: NSObject {
func sendDataToFirstViewController(myData: String)
}
public var delegate: MyDataSendingDelegateProtocol? = nil
Sending a value form framework as
delegate?.sendDataToFirstViewController(myData: "hello world")
In the main app
class ViewController: UIViewController, MyDataSendingDelegateProtocol{
func sendDataToFirstViewController(myData: String) {
print("from frame work \(myData)")
}
}
Accessing my framework VC
public class OOB_View : UIViewController {
public func registraionView() -> UIViewController {
let storyboard = UIStoryboard.init(name: "main", bundle: Bundle(for: oobRegVc.self))
let homeVC = storyboard.instantiateViewController(withIdentifier: "view") as! oobRegVc
return homeVC
}
}
In your framework modify the registraionView method to accept the delegate parameter of type MyDataSendingDelegateProtocol and then set it as homeVC's delegate, i.e.
public class OOB_View : UIViewController {
public func registraionView(delegate: MyDataSendingDelegateProtocol) -> UIViewController {
let storyboard = UIStoryboard.init(name: "main", bundle: Bundle(for: oobRegVc.self))
let homeVC = storyboard.instantiateViewController(withIdentifier: "view") as! oobRegVc
homeVC.delegate = delegate
return homeVC
}
}
Now, in your main app, call the method registraionView(delegate:) like so,
let oobClass = OOB_View()
let x = oobClass.registraionView(delegate: self)
x.modalPresentationStyle = .fullScreen
self.present(x, animated: true, completion: nil)
The above code must be somewhere in the ViewController conforming to MyDataSendingDelegateProtocol.
Related
I'm building a separate feature as a swift package. There is a view controller and its storyboard in the package. I'm having a problem instantiating and presenting the view controller. I get this error:
Could not find a storyboard named 'MyIdCardVC' in bundle NSBundle ...
Both MyIdCardVC.swift and MyIdCardVC.storyboard are added to the package.
Here is part of the Package.swift declaration:
let package = Package(
name: "IDCard",
platforms: [
.iOS(.v11)
],
products: [
.library(name: "IDCard", targets: ["IDCard"]),
],
I'm presenting the package's view controller from my app like this:
import UIKit
import IDCard
class ViewController: UIViewController {
override func viewDidLoad() {
super.viewDidLoad()
// Do any additional setup after loading the view.
let vc = IDCard.MyIdCardVC.getStoryboardVC()
present(vc, animated: true, completion: nil)
}
}
the "getStoryboardVC" is a static extension method declared in the package
public extension UIViewController{
public static func getStoryboardVC() -> UIViewController {
let storyboard = UIStoryboard(name: String(describing: self), bundle: nil)
return storyboard.instantiateInitialViewController()!
}
and here how the MyIDCardVC.storyboard looks:
I solved it by using Bundle.module when instantiating the storyboard's view controller. Bundle.module refers to the containing package:
public extension UIViewController{
public static func getStoryboardVC() -> UIViewController {
let storyboard = UIStoryboard(name: String(describing: self),
bundle: Bundle.module)// key part is Bundle.module
return storyboard.instantiateInitialViewController()!
}
}
Then in the app, I present the package view controller like this:
#IBAction func openCard(){
let vc = IDCard.MyIdCardVC.getStoryboardVC() as! IDCard.MyIdCardVC
vc.personNo = "11111"
vc.personId = "8888888"
present(vc, animated: true, completion: nil)
}
and in the storyboard, specify the module and uncheck Inherit Module From Target
This question already has answers here:
How to launch a ViewController from a Non ViewController class?
(7 answers)
Closed 5 years ago.
I would like to know how can I push user back to specific ViewController from regular swift class without being non UIView Class
Example
class nonUI {
function Push() {
//How to send user back to specific VC here?
}
}
This is a generic method you can use with in the class or outside the class for push if required else it will pop if the instance of view controller is in the stack:
func pushIfRequired(className:AnyClass) {
if (UIViewController.self != className) {
print("Your pushed class must be child of UIViewController")
return
}
let storyboard : UIStoryboard = UIStoryboard(name: "Main", bundle: nil)
var isPopDone = false
let mainNavigation = UIApplication.shared.delegate?.window??.rootViewController as? UINavigationController
let viewControllers = mainNavigation!.viewControllers
for vc in viewControllers {
if (type(of: vc) == className) {
mainNavigation?.popToViewController(vc, animated: true)
isPopDone = true
break
}
}
if isPopDone == false{
let instanceSignUp = storyboard.instantiateViewController(withIdentifier: NSStringFromClass(className)) // Identifier must be same name as class
mainNavigation?.pushViewController(instanceSignUp, animated: true)
}
}
USES
pushIfRequired(className: SignupVC.self)
You could also utilise the NotificationCenter to achieve a loosely coupled way to "request a view controller"; if you will.
For example, create a custom UINavigationController that observes for the custom Notification and upon receiving one, looks for the requested UIViewController and pops back to it.
class MyNavigationController : UINavigationController {
override func viewDidLoad() {
super.viewDidLoad()
NotificationCenter.default.addObserver(forName: NSNotification.Name("RequestViewController"), object: nil, queue: OperationQueue.main) { [unowned self] (note) in
guard let targetType = note.object as? UIViewController.Type else {
print("Please provide the type of the VC to display as an `object` for the notification")
return
}
// Find the first VC of the requested type
if let targetVC = self.viewControllers.first(where: { $0.isMember(of: targetType) }) {
self.popToViewController(targetVC, animated: true)
}
else {
// do what needs to be done? Maybe instantiate a new object and push it?
}
}
}
}
Then in the object you want to go back to a specific ViewController, post the notification.
#IBAction func showViewController(_ sender: Any) {
NotificationCenter.default.post(Notification(name: NSNotification.Name("RequestViewController"), object: ViewController2.self))
}
Now, it's also fairly easy to adopt this method for other presentation-styles.
Instead of using the NotificationCenter, you could also muster up a Mediator to achieve the loose coupling.
You can't. UIViewController and its subclass only can handle navigate between screen.
In your case, need pass link (variable) to navigation controller in custom class.
Like:
class nonUI {
var navigationController: UINavigationController?
init(navigationController: UINavigationController) {
self.navigationController = navigationController
}
function Push() {
//How to send user back to specific VC here?
navigationController?.popViewController(animated: true)
}
}
I'm an android developer. in android, when user login in application, I will re-open the MainActivity class ( controller ) to refresh some views.
in iOS applications, how to do this scenario ?
You can reopen you default/LandingViewController.
Suppose you have a View Controller with name LandingViewController
When you successfully logged in all you need is to re instantiate the LandingViewController
In AppDelegate class make a function with name
func userDidLoggedIn(){
let storyboard = UIStoryboard(name: "Main", bundle: nil)//Replace Main With your own storyboard name containing LandingViewController
let landingViewController = storyboard.instantiateViewController(withIdentifier: "LandingViewControllerIdentifier")//Pass your LandingViewController Identier that you have set in your storyboard file.
guard let subviews = self.window?.subviews else {
return
}
for view in subviews {
view.removeFromSuperview()
}
self.window?.rootViewController = landingViewController
}
Now Simply Call this Function where ever in the entire project like this In your case write below lines in the completion block of login request API.
let delegate = UIApplication.shared.delegate as! AppDelegate
delegate. userDidLoggedIn()
Once user login, you can change your rootviewcontroller like this:
var nav_VC: UIViewController?
func onSuccessfulLogin()
{
let storyboard = UIStoryboard.init(name: "Main", bundle: nil)
nav_VC = nil
if nav_VC == nil {
nav_VC = storyboard.instantiateViewController(withIdentifier: "home_nav")
}
self.window?.rootViewController = nav_VC
self.window?.makeKeyAndVisible()
}
Question:
How might one write a custom segue that would allow you to embed view controllers from a different storyboard?
Context:
I am trying to write a custom segue with which I can link from one storyboard to another. A good article on atomicobject.com illustrates how to create a segue that originates from a button / event etc. Translated into swift, and allowing for non UINavigationControllers, the code looks like:
public class SegueToStoryboard : UIStoryboardSegue {
private class func viewControllerInStoryBoard(identifier:String, bundle:NSBundle? = nil)
-> UIViewController?
{
let boardScene = split(identifier, { $0 == "." }, maxSplit: Int.max, allowEmptySlices: false)
switch boardScene.count {
case 2:
let sb = UIStoryboard(name: boardScene[0], bundle: bundle)
return sb.instantiateViewControllerWithIdentifier(boardScene[1]) as? UIViewController
case 1:
let sb = UIStoryboard(name: boardScene[0], bundle: bundle)
return sb.instantiateInitialViewController() as? UIViewController
default:
return nil
}
}
override init(identifier: String!,
source: UIViewController,
destination ignore: UIViewController) {
let target = SegueToStoryboard.viewControllerInStoryBoard(identifier, bundle: nil)
super.init(identifier: identifier, source: source,
destination:target != nil ? target! : ignore)
}
public override func perform() {
let source = self.sourceViewController as UIViewController
let dest = self.destinationViewController as UIViewController
source.addChildViewController(dest)
dest.didMoveToParentViewController(source)
source.view.addSubview(dest.view)
// source.navigationController?.pushViewController(dest, animated: true)
}
}
Problem:
The problem that I am having with both their Obj-C and the above Swift code is that when you try to use the via a container view (with semantics of an embed segue - starting with an embed segue, deleting the segue, and then use the above custom segue), it crashes before ever calling the segue code with the following method-not-found error:
*** Terminating app due to uncaught exception 'NSUnknownKeyException', reason: '[<UIStoryboardSegueTemplate 0x7ffc8432a4f0>
setValue:forUndefinedKey:]: this class is not key value
coding-compliant for the key containerView.'
I have tried to inspect the address listed but get no meaningful results. I do the see the bold statement that it expecting the containerView but don't know how one might isolate, satisfy, and/or work around this problem.
Summary:
My end goal is to embed view controllers defined in separate storyboards to facilitate collaboration and testing without having to write additional code (a non invasive solution). Does anyone have any insight into how to accomplish this greater task? I could fall back to hybrid approach of calling performSegue, but would like to find a single, contained, and complete solution. The above code gets there for event driven (buttons etc) segues, but not with the embed segue.
Any input is appreciated, thanks in advance.
Your approach works fine for custom segues to push / display modally other view controllers but not for embed segues. The reason for this is that the "Embed" segue is not a subclass of UIStoryboardSegue but inherits from UIStoryboardSegueTemplate, which is a private API.
Unfortunately I couldn't find a better way to achieve what you want than with the hybrid approach.
My way is to link the containerView and delete the viewDidLoad segue from it. and manually call the segue on viewdidLoad
public protocol EmbeddingContainerView {
var containerView: UIView! { get set }
}
public class CoreSegue: UIStoryboardSegue {
public static func instantiateViewControllerWithIdentifier(identifier: String) -> UIViewController {
let storyboard = UIStoryboard(name: "Core", bundle: NSBundle(forClass: self))
let controller = storyboard.instantiateViewControllerWithIdentifier(identifier) as! UIViewController
return controller
}
var isPresent = false
var isEmbed = false
override init!(identifier: String?, source: UIViewController, destination: UIViewController) {
if var identifier = identifier {
if identifier.hasPrefix("present ") {
isPresent = true
identifier = identifier.substringFromIndex(advance(identifier.startIndex, count("present ")))
}
if identifier.hasPrefix("embed ") {
isEmbed = true
identifier = identifier.substringFromIndex(advance(identifier.startIndex, count("embed ")))
}
let controller = CoreSegue.instantiateViewControllerWithIdentifier(identifier)
super.init(identifier: identifier, source: source, destination: controller)
} else {
super.init(identifier: identifier, source: source, destination: destination)
}
}
public override func perform() {
if let source = sourceViewController as? UIViewController, dest = destinationViewController as? UIViewController {
if isPresent {
let nav = UINavigationController(rootViewController: dest)
nav.navigationBarHidden = true // you might not need this line
source.presentViewController(nav, animated: true, completion: nil)
} else if isEmbed {
if let contentView = (source as? EmbeddingContainerView)?.containerView {
source.addChildViewController(dest)
contentView.addSubview(dest.view)
dest.view.fullDimension() // which comes from one of my lib
}
} else {
source.navigationController?.pushViewController(destinationViewController as! UIViewController, animated: true)
}
}
}
}
and later in your code:
class MeViewController: UIViewController, EmbeddingContainerView {
#IBOutlet weak var containerView: UIView!
override func viewDidLoad() {
super.viewDidLoad()
performSegueWithIdentifier("embed Bookings", sender: nil)
}
}
I'm trying to write a little extension in Swift to handle instantiation of a UIViewController from a storyboard.
My idea is the following: Since UIStoryboard's method instantiateViewControllerWithIdentifier needs an identifier to instantiate a given storyboard's view controller, why don't assign every view controller in my storyboard an identifier equal to its exact class name (i.e a UserDetailViewController would have an identifier of "UserDetailViewController"), and, create a class method on UIViewController that would:
accept a UIStoryboard instance as a unique parameter
get the current class name as a string
call instantiateViewControllerWithIdentifier on the storyboard instance with the class name as a parameter
get the newly created UIViewController instance, and return it
So, instead of (which repeats the class name as a string, not very nice)
let vc = self.storyboard?.instantiateViewControllerWithIdentifier("UserDetailViewController") as UserDetailViewController
it would be:
let vc = UserDetailViewController.instantiateFromStoryboard(self.storyboard!)
I used to do it in Objective-C with the following category:
+ (instancetype)instantiateFromStoryboard:(UIStoryboard *)storyboard
{
return [storyboard instantiateViewControllerWithIdentifier:NSStringFromClass([self class])];
}
But I'm completely stuck with the Swift version. I hope is that there is some kind of way to do it.
I tried the following:
extension UIViewController {
class func instantiateFromStoryboard(storyboard: UIStoryboard) -> Self {
return storyboard.instantiateViewControllerWithIdentifier(NSStringFromClass(Self))
}
}
Returning Self instead of AnyObject allows the type inference to work. Otherwise, I would have to cast every single return of this method, which is annoying, but maybe you have a better solution?
This gives me the error: Use of unresolved identifier 'Self'
The NSStringFromClass part seems to be the problem.
What do you think?
Is there any way to return Self from class functions?
How would you get this working without the need to cast the return value every time? (i.e keeping -> Self as return value)
How about writing an extension to UIStoryboard instead of UIViewController?
extension UIStoryboard {
func instantiateVC<T: UIViewController>() -> T? {
// get a class name and demangle for classes in Swift
if let name = NSStringFromClass(T.self)?.componentsSeparatedByString(".").last {
return instantiateViewControllerWithIdentifier(name) as? T
}
return nil
}
}
Even adopting this approach, cost of an use side is low as well.
let vc: UserDetailViewController? = aStoryboard.instantiateVC()
Thanks to MartinR and his answer, I know the answer:
UPDATE: rewritten with a protocol.
Instantiable
protocol StringConvertible {
var rawValue: String {get}
}
protocol Instantiable: class {
static var storyboardName: StringConvertible {get}
}
extension Instantiable {
static func instantiateFromStoryboard() -> Self {
return instantiateFromStoryboardHelper()
}
private static func instantiateFromStoryboardHelper<T>() -> T {
let identifier = String(describing: self)
let storyboard = UIStoryboard(name: storyboardName.rawValue, bundle: nil)
return storyboard.instantiateViewController(withIdentifier: identifier) as! T
}
}
//MARK: -
extension String: StringConvertible { // allow string as storyboard name
var rawValue: String {
return self
}
}
StoryboardName
enum StoryboardName: String, StringConvertible {
case main = "Main"
//...
}
Usage:
class MyViewController: UIViewController, Instantiable {
static var storyboardName: StringConvertible {
return StoryboardName.main //Or you can use string value "Main"
}
}
let viewController = MyController.instantiateFromStoryboard()
you can create UIViewController Instance like this:
Create enum with all your storyboard name.
enum AppStoryboard: String {
case main = "Main"
case profile = "Profile"
}
Then, here is the extension for instantiate UIViewController
extension UIViewController {
class func instantiate<T: UIViewController>(appStoryboard: AppStoryboard) -> T {
let storyboard = UIStoryboard(name: appStoryboard.rawValue, bundle: nil)
let identifier = String(describing: self)
return storyboard.instantiateViewController(withIdentifier: identifier) as! T
}
}
Usage:
let profileVC: ProfileVC = ProfileVC.instantiate(appStoryboard: .profile)
self.navigationController?.pushViewController(profileVC,animated:true)
We are porting our objective c project to swift. We have split the project into modules. Modules have their own storyboards. We have extended your(even our's as well) problem's solution to one more level by avoiding explicit storyboard names.
// Add you modules here. Make sure rawValues refer to a stroyboard file name.
enum StoryModule : String {
case SomeModule
case AnotherModule = "AnotherModulesStoryBoardName"
// and so on...
}
extension UIStoryboard {
class func instantiateController<T>(forModule module : StoryModule) -> T {
let storyboard = UIStoryboard.init(name: module.rawValue, bundle: nil);
let name = String(T).componentsSeparatedByString(".").last
return storyboard.instantiateViewControllerWithIdentifier(name!) as! T
}
}
// Some controller whose UI is in a stroyboard named "SomeModule.storyboard",
// and whose storyboardID is the class name itself, ie "MyViewController"
class MyViewController : UIViewController {
// Controller Code
}
// Usage
class AClass
{
// Here we must alwasy provide explicit type
let viewController : MyViewController = UIStoryboard.instantiateController(forModule: StoryModule.SomeModule)
}
Two things:
Class constructors in Objective-C are convenience initializers in Swift. Use convenience init rather than class func.
NSStringFromClass(Self) with NSStringFromClass(self.type).
Here is a modern Swift example, based on #findall's solution:
extension UIStoryboard {
func instantiate<T>() -> T {
return instantiateViewController(withIdentifier: String(describing: T.self)) as! T
}
static let main = UIStoryboard(name: "Main", bundle: nil)
}
Usage:
let userDetailViewController = UIStoryboard.main.instantiate() as UserDetailViewController
I think it is ok to fail when trying to instantiate a view controller from a storyboard as this kind of problem should be detected soon.
Or, you can do so
func instantiateViewControllerWithIdentifier<T>(_ identifier: T.Type) -> T {
let identifier = String(describing: identifier)
return instantiateViewController(withIdentifier: identifier) as! T
}
Use protocol in UIViewController to reach your thoughts
let vc = YourViewController.instantiate(from: .StoryboardName)
You can see the use of my link :D
https://github.com/JavanC/StoryboardDesignable
You can add this extension :-
extension UIStoryboard{
func instantiateViewController<T:UIViewController>(type: T.Type) -> T? {
var fullName: String = NSStringFromClass(T.self)
if let range = fullName.range(of:".", options:.backwards, range:nil, locale: nil){
fullName = fullName.substring(from: range.upperBound)
}
return self.instantiateViewController(withIdentifier:fullName) as? T
}
}
And can instantiate view controller like this :-
self.storyboard?.instantiateViewController(type: VC.self)!
In complement for the version of #ChikabuZ, here mine that takes into account which bundle the storyboard is in (for example, if your storyboads are in another bundle than your app). I added also a small func if you want to use xib instead of storyboad.
extension UIViewController {
static func instantiate<TController: UIViewController>(_ storyboardName: String) -> TController {
return instantiateFromStoryboardHelper(storyboardName)
}
static func instantiate<TController: UIViewController>(_ storyboardName: String, identifier: String) -> TController {
return instantiateFromStoryboardHelper(storyboardName, identifier: identifier)
}
fileprivate static func instantiateFromStoryboardHelper<T: UIViewController>(_ name: String, identifier: String? = nil) -> T {
let storyboard = UIStoryboard(name: name, bundle: Bundle(for: self))
return storyboard.instantiateViewController(withIdentifier: identifier ?? String(describing: self)) as! T
}
static func instantiate<TController: UIViewController>(xibName: String? = nil) -> TController {
return TController(nibName: xibName ?? String(describing: self), bundle: Bundle(for: self))
}
}
I had a similar thought and settled on using the extension below. It still uses the normal instantiation process, but removes reliance on stringly typed Storyboard and View Controller names:
let myVC = UIStoryboard(.main).instantiate(MyViewController.self)
The return type above is pre-cast to MyViewController, not the standard UIViewController.
extension UIStoryboard {
enum Name: String {
case main = "Main"
case launch = "LaunchScreen"
case other = "Other"
}
convenience init(_ name: Name, bundle: Bundle? = nil) {
self.init(name: name.rawValue, bundle: bundle)
}
func instantiate<T: UIViewController>(_ type: T.Type) -> T {
instantiateViewController(withIdentifier: String(describing: type)) as! T
}
}
Note that you must ensure that each VC's Storyboard Identifier exactly matches its class name! Failure to do so will result in the exception:
Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: 'Storyboard (<UIStoryboard: 0x6000035c04e0>) doesn't contain a view controller with identifier 'MyViewController''