URLNavigator

⛵️ URLNavigator provides an elegant way to navigate through view controllers by URLs. URL patterns can be mapped by using URLNavigator.map(_:_:) function.

URLNavigator can be used for mapping URL patterns with 2 kind of types: URLNavigable and URLOpenHandler. URLNavigable is a type which defines an custom initializer and URLOpenHandler is a closure which can be executed. Both an initializer and a closure receive an URL and placeholder values.

Getting Started

1. Mapping URL Patterns

URL patterns can contain placeholders. Placeholders will be replaced with matching values from URLs. Use < and > to make placeholders. Placeholders can have types: string(default), int, float, and path.

Here's an example of mapping URL patterns with view controllers and a closure. View controllers should conform a protocol URLNavigable to be mapped with URL patterns. See Implementing URLNavigable section for details.

Navigator.map("myapp://user/<int:id>", UserViewController.self)
Navigator.map("myapp://post/<title>", PostViewController.self)

Navigator.map("myapp://alert") { url, values in
  print(url.queryParameters["title"])
  print(url.queryParameters["message"])
  return true
}

Note: Global constant Navigator is a shortcut for URLNavigator.default.

2. Pushing, Presenting and Opening URLs

URLNavigator can push and present view controllers and execute closures with URLs.

Provide the from parameter to push() to specify the navigation controller which the new view controller will be pushed. Similarly, provide the from parameter to present() to specify the view controller which the new view controller will be presented. If the nil is passed, which is a default value, current application's top most view controller will be used to push or present view controllers.

present() takes an extra parameter: wrap. If true is specified, the new view controller will be wrapped with a UINavigationController. Default value is false.

Navigator.push("myapp://user/123")
Navigator.present("myapp://post/54321", wrap: true)

Navigator.open("myapp://alert?title=Hello&message=World")

For full documentation, see URLNavigator Class Reference.

3. Implementing URLNavigable

View controllers should conform a protocol URLNavigable to be mapped with URLs. A protocol URLNavigable defines an failable initializer with parameter navigation which contains url, values, mappingContext and navigationContext as properties.

Property url is an URL that is passed from URLNavigator.push() and URLNavigator.present(). Parameter values is a dictionary that contains URL placeholder keys and values. Parameter mappingContext is a context passed from a map() function. Parameter navigationContext is a dictionary which contains extra values passed from push() or present().

final class UserViewController: UIViewController, URLNavigable {

  init(userID: Int) {
    super.init(nibName: nil, bundle: nil)
    // Initialize here...
  }

  convenience init?(navigation: Navigation) {
    // Let's assume that the user id is required
    guard let userID = navigation.values["id"] as? Int else { return nil }
    self.init(userID: userID)
  }
    
  required init?(coder aDecoder: NSCoder) {
    fatalError("init(coder:) has not been implemented")
  }

}

Note: URLConvertible is a protocol that URL and String conforms.

Installation

For iOS 8+ projects with CocoaPods:
```
pod 'URLNavigator'
```
For iOS 8+ projects with Carthage:
```
github "devxoul/URLNavigator"
```

Example

You can find an example app here.

Build and install the example app.
Open Safari app
Enter navigator://user/devxoul in the URL bar.
The example app will be launched.

Tips and Tricks

Where to Map URLs

I'd prefer using separated URL map file.

struct URLNavigationMap {

  static func initialize() {
    Navigator.map("myapp://user/<int:id>", UserViewController.self)
    Navigator.map("myapp://post/<title>", PostViewController.self)

    Navigator.map("myapp://alert") { url, values in
      print(url.queryParameters["title"])
      print(url.queryParameters["message"])
      self.someUtilityMethod()
      return true
    }
  }

  private static func someUtilityMethod() {
    print("This method is really useful")
  }

}

Then call initialize() at AppDelegate's application:didFinishLaunchingWithOptions:.

@UIApplicationMain
final class AppDelegate: UIResponder, UIApplicationDelegate {

  func application(
    _ application: UIApplication,
    didFinishLaunchingWithOptions launchOptions: [UIApplicationLaunchOptionsKey: Any]?
  ) -> Bool {
    // Navigator
    URLNavigationMap.initialize()
    
    // Do something else...
  }
}

Implementing AppDelegate Launch Option URL

It's available to open your app with URLs if custom schemes are registered. In order to navigate to view controllers with URLs, you'll have to implement application:didFinishLaunchingWithOptions: method.

func application(
  _ application: UIApplication,
  didFinishLaunchingWithOptions launchOptions: [UIApplicationLaunchOptionsKey: Any]?
) -> Bool {
  // ...
  if let url = launchOptions?[.url] as? URL {
    if let opened = Navigator.open(url)
    if !opened {
      Navigator.push(url)
    }
  }
  return true
}

Implementing AppDelegate Open URL Method

You'll might want to implement custom URL open handler. Here's an example of using URLNavigator with other URL open handlers.

func application(_ application: UIApplication, open url: URL, sourceApplication: String?, annotation: Any) -> Bool {
  // If you're using Facebook SDK
  let fb = FBSDKApplicationDelegate.sharedInstance()
  if fb.application(application, open: url, sourceApplication: sourceApplication, annotation: annotation) {
    return true
  }

  // URLNavigator Handler
  if Navigator.open(url) {
    return true
  }

  // URLNavigator View Controller
  if Navigator.present(url, wrap: true) != nil {
    return true
  }

  return false
}

Using with Storyboard

It's not yet available to initialize view controllers from Storyboard. However, you can map the closures alternatively.

Navigator.map("myapp://post/<int:id>") { url, values in
  guard let postID = values["id"] as? Int,
    let postViewController = UIStoryboard(name: "Main", bundle: nil).instantiateInitialViewController()
    else { return false }
  Navigator.push(postViewController)
  return true
}

Then use Navigator.open() instead of Navigator.push():

Navigator.open("myapp://post/12345")

Setting Default Scheme

Set scheme property on URLNavigator instance to get rid of schemes in every URLs.

Navigator.scheme = "myapp"
Navigator.map("/user/<int:id>", UserViewController.self)
Navigator.push("/user/10")

This is totally equivalent to:

Navigator.map("myapp://user/<int:id>", UserViewController.self)
Navigator.push("myapp://user/10")

Setting scheme property will not affect other URLs that already have schemes.

Navigator.scheme = "myapp"
Navigator.map("/user/<int:id>", UserViewController.self) // `myapp://user/<int:id>`
Navigator.map("http://<path>", MyWebViewController.self) // `http://<path>`

Passing Context when Mapping

let context = Foo()
Navigator.map("myapp://user/10", UserViewController.self, context: context)

Passing Extra Values when Pushing or Presenting

let context: [AnyHashable: Any] = [
  "fromViewController": self
]
Navigator.push("myapp://user/10", context: context)
Navigator.present("myapp://user/10", context: context)

License

URLNavigator is under MIT license. See the LICENSE file for more info.

sxua / URLNavigator