zero) aceholder = "Login Name" nameTextField.borderStyle =. Next, in viewDidLoad() after the view.addSubview(loginButton) line but before constraintsInit() line add: nameTextField = UITextField(frame.
#Appdelete make tab bar vc root window swift 4 code#
Add the following code just below the var loginButton: UIButton! line: var nameTextField: UITextField! var passwordTextField: UITextField! Let’s move along a little faster now and add the remainder of our simple login form. We will be using them more throughout this article, so if they’re new to you, just follow along for now.īack in viewDidLoad() add this line just after view.addSubview(loginButton): constraintsInit()īuild and run and you should see your login button sitting right there in the center of the view. They are very human-readable and easy to understand, but explaining them in-depth is beyond the scope of this article. If you are unfamiliar with anchors, I highly recommend finding an anchors tutorial. What we have done here is align loginButton’s center X and center Y anchors to view’s center X and center Y anchors respectively. Modify application(_:didFinishLaunchingWithOptions:) with this code: func application(_ application: UIApplication, didFinishLaunchingWithOptions launchOptions: ?) -> Bool You will see a window property of type UIWindow? and, other than a few empty functions, the only real code is in the method application(_:didFinishLaunchingWithOptions:), and that only contains a return true statement. It only takes a small amount of code to remedy this situation. While that may sound like a positive, it also means that there are aspects of working with UIKit that you’ve been unaware of. This is all something that storyboards handle automatically without you realizing it. And, even if it did, the ViewController.swift that Xcode creates for you is no longer set as the window’s root view controller. This is because your application no longer has a window. If you build and run now, the project will build successfully and the app will run, but you’ll only see a black screen. So, let’s find out what it takes to get rolling without storyboards. All layout-related settings will be right in front of you in code, not hiding in the dozens of places that settings can be tucked away in the Xcode inspectors. Not only will this make PRs easier to review, but hunting down layout-related bugs becomes infinitely easier. Modified constraint: (equalTo: passwordTextField.bottomAnchor, constraint: 40) Original constraint: (equalTo: passwordTextField.bottomAnchor, constraint: 20) So, how would this modification in a programmatic layout look in this example?
What did I change here? You know it’s supposed to be a constraint between a button control and text field, but are you certain that pYg-JC-an0 and Kfc-mn-gVn are the correct controls? You can scan through the XML to find those two values, but what if it had been a complex view with dozens of controls and I modified the spacing on all of them? Do you really have the time to track all of them down? Wouldn’t it be easier if the code were right in front of you, in the view controller, where all of the other view logic is contained? I make the change, submit a PR, and assign you as a reviewer. The designer has asked that we increase that to 40. The button has a vertical constraint to one of the text fields and that constraint has a constant of 20.
I have a simple, single-view application with a form that contains two text fields and a single button. And cherrypicking code from a storyboard XML is so prone to errors that you’re better off redoing the work, which eliminates one of the advantages of having code repositories to begin with. So, why do so many team environments trend towards removing storyboards and XIBs? One of the main reasons teams move away from storyboards, other than the merge conflict and blocking issues, is that most of the property values aren’t easily surfaced for review. And, as we all saw with the debut of SwiftUI at WWDC2019, storyboards really are going to become a thing of the past. The biggest benefit by far is understanding UIKit better than you ever could by sticking with storyboards. There are methods to mitigate these issues, such as splitting out storyboards and XIBs, but they aren’t foolproof, and once you get used to going storyboard-less you’ll begin to see the benefits. If these things haven’t happened to you yet, they will. You’ve probably also been blocked by co-workers who needed to make a storyboard modification before you could do a specific task. If you’ve ever worked in a team environment before, you’ve likely had some very difficult attempts to resolve merge conflicts with storyboards. I am a very visual person and personally fought this approach, so I can understand if you have as well.
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