Barest minimum code to present a UIView - ios

Question

What's the absolute bare minimum code to create a project that creates a UIView and shows it on the screen of an iOS device?
Without Storyboards, templates or any other contrivance. Just the barest presentation of a UIView.
I appreciate the templates are there to make things "easier", but for the sake of comprehending how everything works together, I'd like to try to conceive the frameworks and their relationships with the OS in the barest, truly code based form.
i.e. without Storyboards and all their processes. Just purely in code.
I've tried using google to find something with someone discussing iOS in an holistic manner, so as to view Views with clarity... but it's all about "ease" rather than understanding, so far as I can see.
With Swift.
// All puns were non-intential byproducts of irritation.
EDIT:::
How do I even start a new Project without a View Controller, Storyboard etc? There seems to be only storyboard based templates, and no way to start a "blank" project.

Answer 1

barest minimum would be this, just place this in your app delegate, delete the other .swift files, and this should be the barest you need:
import UIKit
#UIApplicationMain
class AppDelegate: UIResponder, UIApplicationDelegate {
var window: UIWindow?
var rootViewController: UINavigationController?
func application(application: UIApplication, didFinishLaunchingWithOptions launchOptions: [NSObject: AnyObject]?) -> Bool {
self.window = UIWindow(frame: UIScreen.mainScreen().bounds)
rootViewController = UINavigationController(rootViewController: ViewController())
self.window!.rootViewController = rootViewController
self.window!.makeKeyAndVisible()
return true
}
}
this requires Zero storyboards, BUT if you want add a VIEW to all of this and have control over that uiview, then do this:
import UIKit
#UIApplicationMain
class AppDelegate: UIResponder, UIApplicationDelegate {
var window: UIWindow?
var rootViewController: UINavigationController?
func application(application: UIApplication, didFinishLaunchingWithOptions launchOptions: [NSObject: AnyObject]?) -> Bool {
self.window = UIWindow(frame: UIScreen.mainScreen().bounds)
var firstVC = UIViewController()
var firstVCView = UIView()
firstVCView.backgroundColor = UIColor.redColor()
firstVC.view = firstVCView
rootViewController = UINavigationController(rootViewController: firstVC) self.window!.rootViewController = rootViewController
self.window!.makeKeyAndVisible()
return true
}
}
i can show you from the start, ill start a brand new project and strip it:
here's how:
select sinlge view application project
go into info.plist file, delete these two entries:
Then, delete the storyboard, and the nib.
Keep the "ViewController.swift" file
place this in your AppDelegate.swift:
import UIKit
#UIApplicationMain
class AppDelegate: UIResponder, UIApplicationDelegate {
var window: UIWindow?
var rootViewController: UINavigationController?
func application(application: UIApplication, didFinishLaunchingWithOptions launchOptions: [NSObject: AnyObject]?) -> Bool {
self.window = UIWindow(frame: UIScreen.mainScreen().bounds)
rootViewController = UINavigationController(rootViewController: ViewController())
self.window!.rootViewController = rootViewController
self.window!.makeKeyAndVisible()
return true
}
}
then, do this, click no the button "use asset catalog"
the click on the pop up box that you want to use an asset catalog, then make sure this field is blank, where it says "launch screen file"
compile and run your project

Answer 2

A completely empty application with an app delegate, in didFinishLaunchingWithOptions this will present a view:
self.window.rootViewController = [UIViewController new];
there is a view in UIViewController