components/ShadowElevations/examples/ShadowElevationsTypicalUseExample.swift

// Copyright 2017-present the Material Components for iOS authors. All Rights Reserved.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

import UIKit
import Foundation
import MaterialComponents.MaterialAppBar
import MaterialComponents.MaterialShadowElevations
import MaterialComponents.MaterialShadowLayer

class ShadowElevationsPointsLabelSwift: UILabel {
  
  var elevation: ShadowElevation {
    get {
      let layer = self.layer as! MDCShadowLayer
      return layer.elevation
    }
    set {
      let layer = self.layer as! MDCShadowLayer
      layer.elevation = newValue
    }
  }

  override class var layerClass: AnyClass {
    get {
      return MDCShadowLayer.self
    }
  }
}

class ShadowElevationsTypicalUseExample: UIViewController {

  let appBarViewController = MDCAppBarViewController()
  let paper = ShadowElevationsPointsLabelSwift()

  init() {
    super.init(nibName: nil, bundle: nil)

    self.title = "Shadow Elevations (Swift)"
    self.addChildViewController(appBarViewController)

    let color = UIColor(white: 0.2, alpha:1)
    appBarViewController.headerView.backgroundColor = color
    appBarViewController.navigationBar.tintColor = .white
    appBarViewController.navigationBar.titleTextAttributes = [NSForegroundColorAttributeName : UIColor.white]

    let paperDim = CGFloat(200)
    paper.frame =
      CGRect(x: (view.frame.width - paperDim) / 2, y: paperDim, width: paperDim, height: paperDim)
    view.addSubview(paper)

    paper.elevation = .fabResting
  }

  required init?(coder aDecoder: NSCoder) {
    super.init(coder: aDecoder)
  }

  override func viewDidLoad() {
    super.viewDidLoad()

    view.addSubview(appBarViewController.view)
    appBarViewController.didMove(toParentViewController: self)
  }

  override func viewWillAppear(_ animated: Bool) {
    super.viewWillAppear(animated)
    self.view.backgroundColor = .white

    self.navigationController?.setNavigationBarHidden(true, animated: animated)
  }

}

// MARK: Catalog by convention
extension ShadowElevationsTypicalUseExample {

  class func catalogMetadata() -> [String: Any] {
    return [
      "breadcrumbs": ["Shadow", "Shadow Elevations (Swift)"],
      "primaryDemo": false,
      "presentable": false,
    ]
  }

  func catalogShouldHideNavigation() -> Bool {
    return true
  }
}