iOS/Pods/JSQWebViewController/Source/WebViewController.swift

   1 //
   2 //  Created by Jesse Squires
   3 //  http://www.jessesquires.com
   4 //
   5 //
   6 //  Documentation
   7 //  http://jessesquires.github.io/JSQWebViewController
   8 //
   9 //
  10 //  GitHub
  11 //  https://github.com/jessesquires/JSQWebViewController
  12 //
  13 //
  14 //  License
  15 //  Copyright (c) 2015 Jesse Squires
  16 //  Released under an MIT license: http://opensource.org/licenses/MIT
  17 //
  18
  19 import UIKit
  20 import WebKit
  21
  22
  23 private let titleKeyPath = "title"
  24 private let estimatedProgressKeyPath = "estimatedProgress"
  25
  26
  27 /// An instance of `WebViewController` displays interactive web content.
  28 open class WebViewController: UIViewController {
  29
  30     // MARK: Properties
  31
  32     /// Returns the web view for the controller.
  33     public final var webView: WKWebView {
  34         get {
  35             return _webView
  36         }
  37     }
  38
  39     /// Returns the progress view for the controller.
  40     public final var progressBar: UIProgressView {
  41         get {
  42             return _progressBar
  43         }
  44     }
  45
  46     /// The URL request for the web view. Upon setting this property, the web view immediately begins loading the request.
  47     public final var urlRequest: URLRequest {
  48         didSet {
  49             webView.load(urlRequest)
  50         }
  51     }
  52
  53     /**
  54      Specifies whether or not to display the web view title as the navigation bar title.
  55      The default is `false`, which sets the navigation bar title to the URL host name of the URL request.
  56      */
  57     public final var displaysWebViewTitle: Bool = false
  58
  59     // MARK: Private properties
  60
  61     private final let configuration: WKWebViewConfiguration
  62     private final let activities: [UIActivity]?
  63
  64     private lazy final var _webView: WKWebView = {
  65         let webView = WKWebView(frame: CGRect.zero, configuration: configuration)
  66         webView.addObserver(self, forKeyPath: titleKeyPath, options: .new, context: nil)
  67         webView.addObserver(self, forKeyPath: estimatedProgressKeyPath, options: .new, context: nil)
  68         webView.allowsBackForwardNavigationGestures = true
  69         if #available(iOS 9.0, *) {
  70             webView.allowsLinkPreview = true
  71         }
  72         return webView
  73     }()
  74
  75     private lazy final var _progressBar: UIProgressView = {
  76         let progressBar = UIProgressView(progressViewStyle: .bar)
  77         progressBar.backgroundColor = .clear
  78         progressBar.trackTintColor = .clear
  79         return progressBar
  80     }()
  81
  82     // MARK: Initialization
  83
  84     /**
  85      Constructs a new `WebViewController`.
  86
  87      - parameter urlRequest:    The URL request for the web view to load.
  88      - parameter configuration: The configuration for the web view.
  89      - parameter activities:    The custom activities to display in the `UIActivityViewController` that is presented when the action button is tapped.
  90
  91      - returns: A new `WebViewController` instance.
  92      */
  93     public init(urlRequest: URLRequest, configuration: WKWebViewConfiguration = WKWebViewConfiguration(), activities: [UIActivity]? = nil) {
  94         self.configuration = configuration
  95         self.urlRequest = urlRequest
  96         self.activities = activities
  97         super.init(nibName: nil, bundle: nil)
  98     }
  99
 100     /**
 101      Constructs a new `WebViewController`.
 102
 103      - parameter url: The URL to display in the web view.
 104
 105      - returns: A new `WebViewController` instance.
 106      */
 107     public convenience init(url: URL) {
 108         self.init(urlRequest: URLRequest(url: url))
 109     }
 110
 111     /// :nodoc:
 112     public required init?(coder aDecoder: NSCoder) {
 113         self.configuration = WKWebViewConfiguration()
 114         self.urlRequest = URLRequest(url: URL(string: "http://")!)
 115         self.activities = nil
 116         super.init(coder: aDecoder)
 117     }
 118
 119     deinit {
 120         webView.removeObserver(self, forKeyPath: titleKeyPath, context: nil)
 121         webView.removeObserver(self, forKeyPath: estimatedProgressKeyPath, context: nil)
 122     }
 123
 124
 125     // MARK: View lifecycle
 126
 127     /// :nodoc:
 128     open override func viewDidLoad() {
 129         super.viewDidLoad()
 130         title = urlRequest.url?.host
 131         view.addSubview(_webView)
 132         view.addSubview(_progressBar)
 133
 134         if presentingViewController?.presentedViewController != nil {
 135             navigationItem.leftBarButtonItem = UIBarButtonItem(barButtonSystemItem: .done,
 136                                                                target: self,
 137                                                                action: #selector(didTapDoneButton(_:)))
 138         }
 139
 140         navigationItem.rightBarButtonItem = UIBarButtonItem(barButtonSystemItem: .action,
 141                                                             target: self,
 142                                                             action: #selector(didTapActionButton(_:)))
 143
 144         webView.load(urlRequest)
 145     }
 146
 147     /// :nodoc:
 148     open override func viewWillAppear(_ animated: Bool) {
 149         assert(navigationController != nil, "\(WebViewController.self) must be presented in a \(UINavigationController.self)")
 150         super.viewWillAppear(animated)
 151     }
 152
 153     /// :nodoc:
 154     open override func viewDidDisappear(_ animated: Bool) {
 155         super.viewDidDisappear(animated)
 156         webView.stopLoading()
 157     }
 158
 159     /// :nodoc:
 160     open override func viewDidLayoutSubviews() {
 161         super.viewDidLayoutSubviews()
 162         webView.frame = view.bounds
 163
 164         let isIOS11 = ProcessInfo.processInfo.isOperatingSystemAtLeast(
 165             OperatingSystemVersion(majorVersion: 11, minorVersion: 0, patchVersion: 0))
 166         let top = isIOS11 ? CGFloat(0.0) : topLayoutGuide.length
 167         let insets = UIEdgeInsets(top: top, left: 0, bottom: 0, right: 0)
 168         webView.scrollView.contentInset = insets
 169         webView.scrollView.scrollIndicatorInsets = insets
 170
 171         view.bringSubview(toFront: progressBar)
 172         progressBar.frame = CGRect(x: view.frame.minX,
 173                                    y: topLayoutGuide.length,
 174                                    width: view.frame.size.width,
 175                                    height: 2)
 176     }
 177
 178
 179     // MARK: Actions
 180
 181     @objc private func didTapDoneButton(_ sender: UIBarButtonItem) {
 182         dismiss(animated: true, completion: nil)
 183     }
 184
 185     @objc private func didTapActionButton(_ sender: UIBarButtonItem) {
 186         if let url = urlRequest.url {
 187             let activityVC = UIActivityViewController(activityItems: [url], applicationActivities: activities)
 188             activityVC.popoverPresentationController?.barButtonItem = sender
 189             present(activityVC, animated: true, completion: nil)
 190         }
 191     }
 192
 193
 194     // MARK: KVO
 195
 196     /// :nodoc:
 197     open override func observeValue(forKeyPath keyPath: String?,
 198                                     of object: Any?,
 199                                     change: [NSKeyValueChangeKey : Any]?,
 200                                     context: UnsafeMutableRawPointer?) {
 201         guard let theKeyPath = keyPath , object as? WKWebView == webView else {
 202             super.observeValue(forKeyPath: keyPath, of: object, change: change, context: context)
 203             return
 204         }
 205
 206         if displaysWebViewTitle && theKeyPath == titleKeyPath {
 207             title = webView.title
 208         }
 209
 210         if theKeyPath == estimatedProgressKeyPath {
 211             updateProgress()
 212         }
 213     }
 214
 215     // MARK: Private
 216
 217     private final func updateProgress() {
 218         let completed = webView.estimatedProgress == 1.0
 219         progressBar.setProgress(completed ? 0.0 : Float(webView.estimatedProgress), animated: !completed)
 220         UIApplication.shared.isNetworkActivityIndicatorVisible = !completed
 221     }
 222 }