manual-layout-revisited-playground

gistfile1.txt

//: A UIKit based Playground for presenting user interface
  
import UIKit
import PlaygroundSupport

class MyViewController : UIViewController {
    lazy var view1: UIView = {
      let view = UIView()
      view.backgroundColor = .red
      return view
    }()

    lazy var view2: UIView = {
      let view = UIView()
      view.backgroundColor = .blue
      return view
    }()

    lazy var view3: UIView = {
      let view = UIView()
      view.backgroundColor = .green
      return view
    }()

    lazy var view4: UIView = {
      let view = UIView()
      view.backgroundColor = .yellow
      return view
    }()

    override func loadView() {
      let view = UIView(
        frame: CGRect(
          x: 0,
          y: 0,
          width: 320,
          height: 480
        )
      )
      view.backgroundColor = .white
      view.layer.borderWidth = 1.0
      view.layer.borderColor = UIColor.black.cgColor
      [ view1, view2, view3, view4 ].forEach { view.addSubview($0) }
      self.view = view
    }
}

extension UIView {
  var width: CGFloat {
    get {
      return frame.width
    }
    set(newValue) {
      frame.size.width = newValue
    }
  }

  var height: CGFloat {
    get {
      return frame.height
    }
    set(newValue) {
      frame.size.height = newValue
    }
  }

  var bottom: CGFloat {
    get {
      return frame.maxY
    }
    set(newValue) {
      frame.origin.y = newValue - frame.height
    }
  }

  var top: CGFloat {
    get {
      return frame.minY
    }
    set(newValue) {
      frame.origin.y = newValue
    }
  }

  var left: CGFloat {
    get {
      return frame.minX
    }
    set(newValue) {
      frame.origin.x = newValue
    }
  }

  var bottomRightCorner: CGPoint {
    get {
      return CGPoint(x: frame.maxX, y: frame.maxY)
    }
    set(newValue) {
      frame.origin = CGPoint(
        x: newValue.x - frame.size.width,
        y: newValue.y - frame.size.height
      )
    }
  }
}

func resize(views: [UIView], withWidth width: CGFloat) {
  views.forEach { view in
    view.width = width
  }
}

func resize(views: [UIView], withHeight height: CGFloat) {
  views.forEach { view in
    view.height = height
  }
}

func reposition(views: [UIView], withTop top: CGFloat) {
  views.forEach { view in
    view.top = top
  }
}

func reposition(views: [UIView], withLeft left: CGFloat) {
  views.forEach { view in
    view.left = left
  }
}


func arrangeTopToBottom(views: [UIView]) {
  guard var currentPosition = views.first?.top else { return }

  for view in views {
    view.top = currentPosition
    currentPosition += view.height
  }
}

func resize(view: UIView, in views: [UIView], toFitHeight height: CGFloat) {
  let heightOfViews = views.reduce(CGFloat(0)) { memo, currentView in
    guard view != currentView else { return memo }
    var mutableMemo = memo
    mutableMemo += view.height
    return mutableMemo
  }

  view.height = height - heightOfViews
}

func resize(views:[UIView], toFitHeight height: CGFloat) {
  views.forEach { view in
    view.height = height / CGFloat(views.count)
  }
}

let viewController = MyViewController()

/// --- Demo 1

//viewController.view1.height = 100
//viewController.view1.width = 100
//viewController.view1.bottomRightCorner = viewController.view.bottomRightCorner

/// -- Demo 2

//let views = [
//  viewController.view1,
//  viewController.view2,
//  viewController.view3,
//  viewController.view4
//]
//
//resize(views: views, withWidth: viewController.view.width)
//resize(views: views, withHeight: 50)

/// -- Demo 3

//let views = [
//  viewController.view1,
//  viewController.view2,
//  viewController.view3,
//  viewController.view4
//]
//
//resize(views: views, withWidth: viewController.view.width)
//resize(views: views, withHeight: 50)
//arrangeTopToBottom(views: views)

// -- Demo 4

//let views = [
//  viewController.view1,
//  viewController.view2,
//  viewController.view3,
//  viewController.view4
//]
//
//resize(views: views, withWidth: viewController.view.width)
//resize(views: views, withHeight: 100)
//resize(view: viewController.view3, in: views, toFitHeight: viewController.view.height)
//arrangeTopToBottom(views: views)

// -- Demo 5

//let views = [
//  viewController.view1,
//  viewController.view2,
//  viewController.view3,
//  viewController.view4
//]
//
//resize(views: views, withWidth: viewController.view.width)
//resize(views: views, withHeight: 100)
//resize(views: views, toFitHeight: viewController.view.height)
//arrangeTopToBottom(views: views)


PlaygroundPage.current.liveView = viewController.view