Sorry if this is a beginner question but I'm relatively new to Unit testing and didn't see this asked anywhere.
When I start my unit tests in Swift, I setUp my tests by instantiating my viewController.
My code is set up using MVVM (Model - View - ViewModel). So when I test some of my viewModel methods, they will update the Views (in the ViewController) in the UI. The problem is, Xcode keeps crashing and says that the views in the ViewController are nil? How do I prevent these views from being nil? Am I doing something wrong? How do I instantiate the views within the viewController? I thought this would be automatic.
class WeirdFaceTests: XCTestCase {
var viewController: ViewController?
var tattooModel: ARModel?
var tattooViewModel: ARViewModel?
var mainUIModel: MainUIModel?
var mainUIViewModel: MainUIViewModel?
override func setUp() {
// Put setup code here. This method is called before the invocation of each test method in the class.
super.setUp()
self.viewController = UIStoryboard(name: "Main", bundle: nil).instantiateViewController(withIdentifier: "PrimaryViewController") as! ViewController
self.tattooModel = ARModel(imageName: "blank", tattooType: .new)
self.tattooViewModel = ARViewModel(tattooModel: tattooModel!, delegate: viewController!)
self.mainUIModel = MainUIModel()
self.mainUIViewModel = MainUIViewModel(model: mainUIModel!, delegate: viewController!)
}
Turns out I was missing the self.viewController?.loadView() call in the setUp() method.
The correct code that works without nil views is as follows:
class WeirdFaceTests: XCTestCase {
var viewController: ViewController?
var tattooModel: ARModel?
var tattooViewModel: ARViewModel?
var mainUIModel: MainUIModel?
var mainUIViewModel: MainUIViewModel?
override func setUp() {
// Put setup code here. This method is called before the invocation of each test method in the class.
super.setUp()
self.viewController = UIStoryboard(name: "Main", bundle:nil).instantiateViewController(withIdentifier: "PrimaryViewController") as! ViewController
self.viewController?.loadView()
Related
I'm learning Programmatic UI and am a little bit obsessed with clean code.
I'm currently building a TabBarVC so that I can manage all of my VC's but I get an error message while doing this.
import UIKit
class MainTabBarVC: UITabBarController {
let firstVC = FirstVC()
let secondVC = SecondVC()
let firstNavVC = UINavigationController(rootViewController: firstVC) // Cannot use instance member 'firstVC' within property initializer; property initializers run before 'self' is available
let secondNavVC = UINavigationController(rootViewController: secondVC) // Cannot use instance member 'secondVC' within property initializer; property initializers run before 'self' is available
let viewControllers = [firstNavVC, secondNavVC]
override func viewDidLoad() {
super.viewDidLoad()
self.setupViews()
}
func setupViews() {
// Nav Configs
self.firstVC.view.backgroundColor = .systemBackground
self.firstVC.navigationItem.title = "First Nav"
self.secondVC.view.backgroundColor = .systemBackground
self.secondVC.navigationItem.title = "Second Nav"
// Tab Configs
self.firstNavVC.tabBarItem.title = "First TAB"
self.secondNavVC.tabBarItem.title = "Second TAB"
}
}
I know if I put firtNavVC, secondNavVC, and viewcontrollers inside the setupViews it is gonna work but I don't like it when one function has too many lines of codes especially when it gets bigger.
So except for my question, are there any extension or enum functions that I can easily manage all of my UINavigationController, UITabBarController, and UIViewController such as enumeration that can call the function whenever I need to call or add a new VC.
You could change your lets into lazy vars.
class MainTabBarVC: UITabBarController {
lazy var firstVC = FirstVC()
lazy var secondVC = SecondVC()
lazy var firstNavVC = UINavigationController(rootViewController: firstVC)
lazy var secondNavVC = UINavigationController(rootViewController: secondVC)
lazy var viewControllers = [firstNavVC, secondNavVC]
override func viewDidLoad() {
super.viewDidLoad()
self.setupViews()
}
However, I think your impulse to maintain instance property references to all these view controllers is mistaken. What I would do is just move the lets into setupViews. You don't need a permanent reference to any of these objects; you just need to create them, configure them, and assign the view controllers as children of your tab bar controller (your code is missing that crucial step, by the way).
When I set the ViewController is the root navigation controller in the file Appdelegate.swift, like this:
var viewcontroller=ViewController();
var rootnavigationcontroller=UINavigationController.init(rootViewController: viewcontroller);
self.window?.rootViewController=rootnavigationcontroller;
Then I configure the ViewController like this:
class ViewController: UIViewController,CLLocationManagerDelegate,MKMapViewDelegate{
#IBOutlet weak var MapView: MKMapView!
override func viewDidLoad() {
super.viewDidLoad()
loadLaunchScreen();
Initilize();//Here configure the MapView parameters;
}
Then in the function Initilize(); I receive the error that means the MapView has found nil.
But if I do not set this Viewcontroller as the rootnavigationcontroller in the Appdelegate.swift, I will run well.
I want to ask why and how to solve it?
if you are using storyboards then try this
let stroyboard = UIStoryboard.init(name: "storyboardname", bundle: nil)//nil if its not out of your project
let ViewController = storyboard.instantiateViewController(withIdentifier: "yourstoryboadid")
var rootnavigationcontroller=UINavigationController.init(rootViewController: viewcontroller);
self.window?.rootViewController=rootnavigationcontroller;
above problem can happen when you use storybords and you are instantiate the viewController not from storyboard thats when your outlet found nil because is is not bounded to the outlet
if you are not using storyboards then your code is perfet
If you are not adding rootnavigationcontroller then your ViewController code will not be executed. So you will not get any error. For successfully MapView implementation, bind your MapView #IBOutlet in storyboard or XIB.
I am new to Unit test in Swift. Now I wanted to test my viewController. In viewDidLoad I have an asynchronous call. So that if I want to test my Controller if the data got loaded correctly, the data didn't got loaded. I already read that I have to build in an XCTestExpectation.
So the information I have, I got from this question: XCTest Unit Test data response not set in test after viewDidLoad
The answer there is an example from which I don't know how to implement. My test class looks like this:
import XCTest
#testable import apirequest
class SearchedForViewControllerTests: XCTestCase {
var vc: SearchedForViewController!
override func setUp() {
super.setUp()
let storyboard = UIStoryboard(name: "Main", bundle: Bundle.main)
vc = storyboard.instantiateViewController(withIdentifier: "SearchedForViewController") as! SearchedForViewController
vc.passedString = "garten"
let _ = vc.view
}
func testArticlesShwon() {
print(vc.tableView.numberOfRows(inSection: 0))
}
}
So if I look on my own code the part of viewDidLoad happens in
let _ = vc.view
If I want to build in a Expectation, I have to wait for this part. But the part is not a function. So I don't know how I could tell my Expectation to fulfill after loading.
This may be more of an opinion/design answer, but I would highly recommend testing your ViewController and your Model completely separately.
E.g. when you're testing your VC, manually set the data in your tests, then separately have tests to ensure your model and any networking/async calls are functioning properly.
I am working on a project with Swift and Storyboards. It's a conversion project from a traditional IB and Objective-C project. I am having an issue with a UITableView instantiating when the view is loaded. Let me explain.
The project is a navigation project. Here is an overview of the Storyboard.
The Storyboard's first viewController is HomeViewController and is a landing page that displays general info. The next VC is called FeedViewController shows a number of RSS feeds. You can see an expanded screen shot of the NavigationController, HomeViewController and FeedViewController in the picture below.
My problem is that I can't get the tableView to Instantiate. I first checked to make sure that my tableView was connected as an outlet and that the dataSource and delegate properties were connected. You can see this in the pic below.
In my FeedViewController class I have an Outler property called feedsTableView. You can see the declaration in the code below.
class FeedViewController: UIViewController, UITableViewDataSource, UITableViewDelegate, FLODataHandlerDelegate
{
// View Contoller and Protocol Properties
var floView : FLOViewController?
var dataHandler : FLODataHandler?
// Interface and Content Properties
var refreshControl : UIRefreshControl?
// IBOutlets
#IBOutlet weak var feedsTableView: UITableView!
#IBOutlet weak var backgroundImage: UIImageView!
In the HomeViewController I have a FeedViewController property that I intend to use to gain access to FeedViewController's feedsTableView.
class HomeViewController: UIViewController, FLODataHandlerDelegate, MFMailComposeViewControllerDelegate
{
// View Contoller and Protocol Properties
var feedViewController : FeedViewController?
var dataHandler : FLODataHandler?
When HomeViewController's viewDidLoad() method is called I start the dataHandler - which instantiates the FeedViewController - and set it to my FeedViewController property.
override func viewDidLoad()
{
super.viewDidLoad()
// Set up the gesture recognizer to allow for swiping to the feed VC.
let recognizer = UISwipeGestureRecognizer(target: self, action: Selector("goToNext"))
recognizer.direction = UISwipeGestureRecognizerDirection.Left
self.view.addGestureRecognizer(recognizer)
// Start the data handler
self.setUpDataHandler()
}
setUpDataHandler()
func setUpDataHandler()
{
// Intitalize FeedVC for use later in the VC
let storyboard = UIStoryboard(name: "Main", bundle: nil)
let vc = storyboard.instantiateViewControllerWithIdentifier("FeedViewController") as! FeedViewController
self.feedViewController = vc
}
I also have a fail safe that if someone were to go to the FeedViewController before the setUpDataHandler() method is called then I instantiate FeedViewController here as well.
func goToNext()
{
// Grab the feedViewController so it can be pushed onto the stack. Make sure you set up the storyboard identifier.
let feedVC = self.storyboard!.instantiateViewControllerWithIdentifier("FeedViewController") as! FeedViewController
self.feedViewController = feedVC
self.navigationController!.pushViewController(self.feedViewController!, animated: true)
}
However the feedsTableView is not getting instantiated. In the viewDidLoad() method of FeedViewController I attempt to add the feedsTableView to a UIRefreshController.
override func viewDidLoad()
{
super.viewDidLoad()
self.refreshControl = UIRefreshControl()
self.refreshControl!.addTarget(self, action: "refreshInvoked:state:", forControlEvents: UIControlEvents.ValueChanged)
// See the note in viewDidLoad in FLOViewController.
self.feedsTableView.addSubview(self.refreshControl!)
}
When the app runs I get the following error.
fatal error: unexpectedly found nil while unwrapping an Optional value
The image below shows were this is called. It's the viewDidLoad() of the FeedViewController. As you can see in the picture I even tried instantiating the feedsTableView before adding it to the UIRefreshController and I still get the error.
Any help would be greatly appreciated.
Take care,
Jon
The reason why it doesn't work in the very last case, where you manually instantiate UITableView and assign that to self.feedsTableView, is that self.feedsTableView is declared weak. Thus, the table view comes into existence, is assigned, and vanishes in a puff of smoke because it has no memory management. By the time you get to the last line, self.feedsTableView is nil once again.
Thus, the solution for that last case is to remove the weak designation from your feedsTableView declaration.
That will get you past the crash in that last case. But of course you won't see anything because you are not also inserting the table view into your interface.
I know that this has to be a simple fix, but can't seem to understand why my code is not working. Basically I am trying to send a value from a text field in 1 view to a 2nd view's label.
ViewController.swift
#IBOutlet var Text1st: UITextField
#IBAction func Goto2ndView(sender: AnyObject) {
let view2 = self.storyboard.instantiateViewControllerWithIdentifier("view2") as MyView2
//view2.Label2nd.text=text;
self.navigationController.pushViewController(view2, animated: true)
}
MyView2.swift
#IBOutlet var Label2nd: UILabel
override func viewDidLoad() {
super.viewDidLoad()
var VC = ViewController()
var string = (VC.Text1st.text) //it doesn't like this, I get a 'Can't unwrap Option.. error'
println(string)
}
-------EDITED UPDATED CODE FROM (drewag)-------
ViewController.swift
let text = "text"
var sendString = Text1st.text
println(sendString) //successfully print it out.
let view2 = self.storyboard.instantiateViewControllerWithIdentifier("view2") as MyView2
view2.Label2nd.text=sendString;
self.navigationController.pushViewController(view2, animated: true)
MyView2.swift
#IBOutlet var Label2nd: UILabel
override func viewDidLoad() {
super.viewDidLoad()
var VC = ViewController()
var string = self.Label2nd.text
println(string) //still getting the error of an unwrap optional.none
}
var VC = ViewController() creates a new instance of ViewController. Unless there is a default value, you are not going to get any value out of VC.Text1st.text. You really should use a string variable on your second view controller to pass the data to it.
Also, a note on common formatting:
Class names should start with a capital letter (as you have)
Method / function names should start with a lower case letter
UIViewController subclasses should have "Controller" included in their name, otherwise, it looks like it is a subclass of UIView which is an entirely different level of Model View Controller (the architecture of all UIKit and Cocoa frameworks)
Edit:
Here is some example code:
class ViewController1 : UIViewController {
...
func goToSecondView() {
var viewController = ViewController2()
viewController.myString = "Some String"
self.navigationController.pushViewController(viewController, animated: true)
}
}
class ViewController2 : UIViewController {
var myString : String?
func methodToUseMyString() {
if let string = self.myString {
println(string)
}
}
...
}
Note, I am not creating ViewController2 using a storyboard. I personally prefer avoiding storyboards because they don't scale well and I find editing them to be very cumbersome. You can of course change it to create the view controller out of the storyboard if you prefer.
jatoben is correct that you want to use optional binding. IBOutlets are automatically optionals so you should check the textfield to see if it is nil.
if let textField = VC.Text1st {
println(textField.text)
}
This should prevent your app from crashing, but it will not print out anything because your text field has not yet been initialized.
Edit:
If you want to have a reference to your initial ViewController inside your second you're going to have to change a few things. First add a property on your second viewcontroller that will be for the first view controller:
#IBOutlet var Label2nd: UILabel //existing code
var firstVC: ViewController? //new
Then after you create view2, set it's firstVC as the ViewController you are currently in:
let view2 = self.storyboard.instantiateViewControllerWithIdentifier("view2") as MyView2 //already in your code
view2.firstVC = self //new
Finally in your viewDidLoad in your second view controller, use firstVC instead of the ViewController you recreated. It will look something like this:
override func viewDidLoad() {
super.viewDidLoad()
if let textField = firstVC?.Text2nd {
println(textField.text)
}
}
Use optional binding to unwrap the property:
if let string = VC.Text1st.text {
println(string)
}