A Swift 2 XCode Playground demonstrating the ViewSpec protocol for rapidly generating UI elements. Uses some custom extensions that are not included, so almost certainly won't run in a standard Playground. Also requires an image named "puppy1.jpg" to be in the Resources folder.

ViewSpec.swift

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import Foundation
import XCPlayground
import UIKit

let liveVC = UIViewController()
XCPlaygroundPage.currentPage.liveView = liveVC
/** View specification protocol. Can be used to create a UIView that has the given specs.*/
public protocol ViewSpec {
  var frame: CGRect? { get set }
  var backgroundColor: UIColor? { get set }
  var contentMode: UIViewContentMode? { get set }
  var cornerRadius: CGFloat? { get set }
  var blurStyle: UIBlurEffectStyle? { get set }
  var text: String? { get set }
  var textColor: UIColor? { get set }
  var fontSize: CGFloat? { get set }
  var imageName: String? { get set }
  var subviewSpecs: [ViewSpec]? { get set }
  func build()->UIView
}
/** ViewSpec extension that creates a UIView.*/
extension ViewSpec {
  /** Build a view from the spec. Only defined parameters are applied. If no frame is defined, a default frame of (0, 0, 200, 200) is used. Always returns a UIView, but if text is defined, it is actually a UILabel under the hood. If imageName is defined, it's a UIImageView. If both are defined, it returns a UIView that has a UILabel and UIImageView in a default arrangement: centered horizontally and stacked vertically, image on top. For more precise layout control, define each element as its own ViewSpec in subviewSpecs.*/
  public func build()->UIView {
    //Copy self to avoid needing a mutating func.
    var values = self
    //Declare a UIView and assign it the given frame or a default frame.
    var mainView = UIView()
    if let frm = frame {
      mainView.frame = frm
    } else {
      mainView.frame = CGRectMake(0, 0, 200, 200)
    }
    var label: UILabel?
    var imageView: UIImageView?
    //If text is set, make the label = UILabel with it.
    if let text = values.text {
      label = UILabel()
      label!.text = text
      label!.textAlignment = .Center
      if let txColor = textColor {
        label!.textColor = txColor
      }
      if let fsize = fontSize {
        label!.font = label!.font.fontWithSize(fsize)
      }
      label!.contentMode =? contentMode
    }
    //If imageName is set, make the imageView = UIImageView with it.
    if let imageName = imageName {
      let image = UIImage(named: imageName)
      imageView = UIImageView(image: image)
      imageView!.contentMode =? contentMode
    }
    //If both a label and an imageView have been made, make them subviews with default positioning: centered horizontally and stacked vertically, image on top.
    if label != nil && imageView != nil {
      //Give the image most of the frame height.
      let imageHeight = frame!.height / 5 * 3.85
      imageView?.frame = CGRectMake(0, 0, frame!.width, imageHeight)
      //Give the label the rest.
      let labelHeight = frame!.height - imageHeight
      label?.frame = CGRectMake(0, imageHeight, frame!.width, labelHeight)
      mainView.layoutVerticallyAtCenter([imageView!, label!])
    } else {
      //If either label or imageView is non-nil, assign it to step in as mainView.
      mainView =? label
      mainView =? imageView
    }
    //Apply the values that can exist on every UIView.
    mainView.frame =? values.frame
    mainView.backgroundColor =? values.backgroundColor
    mainView.contentMode =? contentMode
    if let subs = values.subviewSpecs {
      subs.forEach({
        let subCopy = $0
        let newSubview = subCopy.build()
        mainView.addSubview(newSubview)
      })
    }
    //Add a blur effect behind everything, if defined.
    if let bStyle = blurStyle {
      let existingMain = mainView
      existingMain.backgroundColor = nil
      mainView = UIVisualEffectView(effect: UIBlurEffect(style: bStyle))
      mainView.frame = existingMain.frame
      existingMain.frame = existingMain.frame.atOrigin(0, 0)
      mainView.addSubview(existingMain)
    }
    //Round corners, if defined.
    if let cr = values.cornerRadius {
      mainView.layer.cornerRadius = cr
      mainView.clipsToBounds = true
    }
    //Return the modified view.
    return mainView
  }
}
/** Standard ViewSpec implementation.*/
public struct ViewSpecStruct: ViewSpec {
  public var frame: CGRect?
  public var backgroundColor: UIColor?
  public var contentMode: UIViewContentMode?
  public var cornerRadius: CGFloat?
  public var blurStyle: UIBlurEffectStyle?
  public var text: String?
  public var textColor: UIColor?
  public var fontSize: CGFloat?
  public var imageName: String?
  public var subviewSpecs: [ViewSpec]?
  public init(frame: CGRect? = nil,
              backgroundColor: UIColor? = nil,
              contentMode: UIViewContentMode? = nil,
              cornerRadius: CGFloat? = nil,
              blurStyle: UIBlurEffectStyle? = nil,
              text: String? = nil,
              textColor: UIColor? = nil,
              fontSize: CGFloat? = nil,
              imageName: String? = nil,
              subviewSpecs: [ViewSpec]? = nil) {
    self.frame =? frame
    self.backgroundColor =? backgroundColor
    self.contentMode =? contentMode
    self.cornerRadius =? cornerRadius
    self.blurStyle =? blurStyle
    self.text =? text
    self.textColor =? textColor
    self.fontSize =? fontSize
    self.imageName =? imageName
    self.subviewSpecs =? subviewSpecs
  }
}
/** Abstraction of view constants, to allow sizes to define themselves relatively. */
let VC_WIDTH: CGFloat = liveVC.view.width
let BLOCK_SIDE = VC_WIDTH / 2.5
let BLOCK_FRAME = CGRectMake(0, 0, BLOCK_SIDE, BLOCK_SIDE)
let STANDARD_INCREMENT = VC_WIDTH / 28
let SMALL_BLOCK_SIDE = (BLOCK_SIDE / 2) - (STANDARD_INCREMENT * 1.5)
let SMALL_FRAME = CGRectMake(0, 0, SMALL_BLOCK_SIDE, SMALL_BLOCK_SIDE)
let COLUMN_1_X = STANDARD_INCREMENT
let COLUMN_2_X = (STANDARD_INCREMENT * 2) + BLOCK_SIDE
let ROW_1_Y = STANDARD_INCREMENT
let ROW_2_Y = ROW_1_Y + STANDARD_INCREMENT + BLOCK_SIDE
let SMALL_BLOCK_X = STANDARD_INCREMENT
let SMALL_ROW_1_Y = STANDARD_INCREMENT
let SMALL_ROW_2_Y = (STANDARD_INCREMENT * 2) + SMALL_BLOCK_SIDE
let SMALL_ROW_WIDTH = BLOCK_SIDE - (STANDARD_INCREMENT * 2)
/** Create a simple red box using a ViewSpecStruct.*/
let redBoxSpec =
  ViewSpecStruct(frame: BLOCK_FRAME.atOrigin(COLUMN_1_X, ROW_1_Y),
                 backgroundColor: .redColor(),
                 cornerRadius: STANDARD_INCREMENT)
liveVC.view.addSubview(redBoxSpec.build())
/** Create a blue box with subviews using a ViewSpecStruct.*/
//small blocks
let orangeSpec =
  ViewSpecStruct(frame: SMALL_FRAME.atOrigin(SMALL_BLOCK_X, SMALL_ROW_1_Y),
                 backgroundColor: .orangeColor(),
                 cornerRadius: STANDARD_INCREMENT)
let yellowSpec =
  ViewSpecStruct(frame: SMALL_FRAME.atOrigin(SMALL_BLOCK_X, SMALL_ROW_2_Y),
                 backgroundColor: .yellowColor(),
                 cornerRadius: STANDARD_INCREMENT)
//big block
let blueBoxSpec =
  ViewSpecStruct(frame: BLOCK_FRAME.atOrigin(COLUMN_2_X, ROW_1_Y),
                 backgroundColor: .blueColor(),
                 cornerRadius: STANDARD_INCREMENT,
                 subviewSpecs: [orangeSpec, yellowSpec])
liveVC.view.addSubview(blueBoxSpec.build())
/** Using seperate ViewSpecStructs for each, create a green box containing a label and an image.*/
//image
let labelSpec =
  ViewSpecStruct(frame: CGRectMake(SMALL_BLOCK_X, SMALL_ROW_1_Y, SMALL_ROW_WIDTH, SMALL_BLOCK_SIDE),
                 backgroundColor: .orangeColor(),
                 cornerRadius: STANDARD_INCREMENT,
                 text: "test text",
                 fontSize: STANDARD_INCREMENT * 2)
let imageSpec =
  ViewSpecStruct(frame: CGRectMake(SMALL_BLOCK_X, SMALL_ROW_2_Y, SMALL_ROW_WIDTH, SMALL_BLOCK_SIDE),
                 backgroundColor: .yellowColor(),
                 cornerRadius: STANDARD_INCREMENT,
                 imageName: "puppy1.jpg",
                 contentMode: .ScaleAspectFill)
let greenBoxSpec =
  ViewSpecStruct(frame: BLOCK_FRAME.atOrigin(COLUMN_1_X, ROW_2_Y),
                 backgroundColor: .greenColor(),
                 cornerRadius: STANDARD_INCREMENT,
                 subviewSpecs: [labelSpec, imageSpec])
liveVC.view.addSubview(greenBoxSpec.build())

/** Create a purple box spec that includes both a text value and an imageName but no subviews. */
let purpleBoxSpec =
  ViewSpecStruct(frame: BLOCK_FRAME.atOrigin(COLUMN_2_X, ROW_2_Y),
                 backgroundColor: .purpleColor(),
                 cornerRadius: STANDARD_INCREMENT,
                 text: "test text",
                 fontSize: STANDARD_INCREMENT * 1.5,
                 textColor: .whiteColor(),
                 imageName: "puppy1.jpg",
                 contentMode: .ScaleAspectFill)
liveVC.view.addSubview(purpleBoxSpec.build())

/** Create each of those again but as a BlurView.*/
func recreateAllAsBlurView() {
  //The formerly-red view.
  var simpleBlurSpec = redBoxSpec
  simpleBlurSpec.frame?.origin.y = (BLOCK_SIDE * 2) + (STANDARD_INCREMENT * 3)
  simpleBlurSpec.blurStyle = .ExtraLight
  liveVC.view.addSubview(simpleBlurSpec.build())
  //The formerly-blue view.
  var blurWithSimpleSubview = blueBoxSpec
  blurWithSimpleSubview.frame?.origin.y = simpleBlurSpec.frame!.origin.y
  blurWithSimpleSubview.blurStyle = .ExtraLight
  liveVC.view.addSubview(blurWithSimpleSubview.build())
  //The formerly-green view.
  var blurWithLabelAndImageUsingSubviewSpecs = greenBoxSpec
  blurWithLabelAndImageUsingSubviewSpecs.frame?.origin.y = simpleBlurSpec.frame!.origin.y + BLOCK_SIDE + STANDARD_INCREMENT
  blurWithLabelAndImageUsingSubviewSpecs.blurStyle = .ExtraLight
  liveVC.view.addSubview(blurWithLabelAndImageUsingSubviewSpecs.build())
  //The formerly-purple view.
  var blurWithLabelAndImageNotFromSubviewSpecs = purpleBoxSpec
  blurWithLabelAndImageNotFromSubviewSpecs.frame?.origin.y = simpleBlurSpec.frame!.origin.y + BLOCK_SIDE + STANDARD_INCREMENT
  blurWithLabelAndImageNotFromSubviewSpecs.blurStyle = .ExtraLight
  liveVC.view.addSubview(
    blurWithLabelAndImageNotFromSubviewSpecs.build())
  
  
}
recreateAllAsBlurView()


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