Create SplitViewCoordinator to handle split view navigation.

Riot/Modules/SplitView/SplitViewCoordinator.swift

@@ -0,0 +1,193 @@
+/*
+ Copyright 2018 New Vector Ltd
+ 
+ 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 Foundation
+
+final class SplitViewCoordinator: NSObject, SplitViewCoordinatorType {
+    
+    // MARK: - Properties
+    
+    // MARK: Private
+    
+    private let rootRouter: RootRouterType
+    private var session: MXSession?
+    
+    private let splitViewController: UISplitViewController
+    
+    // TODO: Move to TabBarCoordinator
+    private let masterNavigationController: UINavigationController
+    private let masterTabBarController: MasterTabBarController
+    
+    /// Completion called when `popToHomeViewControllerAnimated:` has been completed.
+    private var popToHomeViewControllerCompletion: (() -> Void)?
+    
+    // MARK: Public
+    
+    var childCoordinators: [Coordinator] = []
+    
+    // MARK: - Setup
+    
+    init(router: RootRouterType, session: MXSession?) {
+        self.rootRouter = router
+        self.session = session
+        
+        // TODO: Use a dedicated stoyboard and SwiftGen to access it
+        let storyboard = UIStoryboard(name: "Main", bundle: nil)
+        guard let splitViewController = storyboard.instantiateViewController(withIdentifier: "RiotSplitViewController") as? UISplitViewController else {
+            fatalError("[SplitViewCoordinator] Can't load RiotSplitViewController")
+        }
+        splitViewController.preferredDisplayMode = .allVisible
+        self.splitViewController = splitViewController
+        
+        guard let masterNavigationController = splitViewController.viewControllers.first as? UINavigationController else {
+            fatalError("[SplitViewCoordinator] Can't load masterNavigationController")
+        }
+        self.masterNavigationController = masterNavigationController
+        
+        guard let masterTabBarController = masterNavigationController.viewControllers.first as? MasterTabBarController else {
+            fatalError("[SplitViewCoordinator] Can't load masterTabBarController")
+        }
+        self.masterTabBarController = masterTabBarController
+    }
+    
+    // MARK: - Public methods
+    
+    func start() {
+        self.splitViewController.delegate = self
+        self.rootRouter.setRootModule(self.splitViewController)
+    }
+    
+    func update(with session: MXSession) {
+        self.session = session
+    }
+    
+    func toPresentable() -> UIViewController {        
+        return self.splitViewController
+    }
+    
+    // TODO: Do not expose publicly this method
+    func restorePlaceholderDetails() {                
+        // Be sure that the primary is then visible too.
+        if splitViewController.displayMode == .primaryHidden {
+            splitViewController.preferredDisplayMode = .allVisible
+        }
+        
+        if splitViewController.viewControllers.count == 2 {
+            let mainViewController = splitViewController.viewControllers[0]
+                        
+            let emptyDetailsViewController = self.createPlaceholderDetailsViewController()
+            
+            splitViewController.viewControllers = [mainViewController, emptyDetailsViewController]
+        }
+
+        // Release the current selected item (room/contact/group...).
+        masterTabBarController.releaseSelectedItem()
+    }
+    
+    func popToHome(animated: Bool, completion: (() -> Void)?) {
+        if let secondNavController = self.secondaryNavigationController() {
+            secondNavController.popToRootViewController(animated: animated)
+        }
+
+        // Force back to the main screen if this is not the one that is displayed
+        if masterTabBarController != masterNavigationController.visibleViewController {
+            // Listen to the masterNavigationController changes
+            // We need to be sure that masterTabBarController is back to the screen
+            popToHomeViewControllerCompletion = completion
+            masterNavigationController.delegate = self
+
+            masterNavigationController.popToViewController(masterTabBarController, animated: animated)
+        } else {
+            // Select the Home tab
+            masterTabBarController.selectedIndex = Int(TABBAR_HOME_INDEX)
+            completion?()
+        }
+    }
+    
+    // MARK: - Private methods
+    
+    private func createPlaceholderDetailsViewController() -> UIViewController {
+        let storyboard = UIStoryboard(name: "Main", bundle: Bundle.main)
+        let emptyDetailsViewController = storyboard.instantiateViewController(withIdentifier: "EmptyDetailsViewControllerStoryboardId")
+        return emptyDetailsViewController
+    }
+    
+    func secondaryNavigationController() -> UINavigationController? {
+        guard splitViewController.viewControllers.count == 2, let secondViewController = splitViewController.viewControllers.last as? UINavigationController else {
+            return nil
+        }
+        return secondViewController
+    }
+}
+
+// MARK: - UISplitViewControllerDelegate
+extension SplitViewCoordinator: UISplitViewControllerDelegate {
+    
+    func splitViewController(_ splitViewController: UISplitViewController, separateSecondaryFrom primaryViewController: UIViewController) -> UIViewController? {
+                
+        // Return the top view controller of the master navigation controller, if it is a navigation controller itself.
+        if let topViewController = masterNavigationController.topViewController as? UINavigationController {
+            // Keep the detail scene
+            return topViewController
+        }
+
+        // Else return the default empty details view controller from the storyboard.
+        // Be sure that the primary is then visible too.
+        if splitViewController.displayMode == .primaryHidden {
+            splitViewController.preferredDisplayMode = .allVisible
+        }
+        
+        return self.createPlaceholderDetailsViewController()
+    }
+    
+    func splitViewController(_ splitViewController: UISplitViewController, collapseSecondary secondaryViewController: UIViewController, onto primaryViewController: UIViewController) -> Bool {
+        if (masterTabBarController.currentRoomViewController == nil) && (masterTabBarController.currentContactDetailViewController == nil) && (masterTabBarController.currentGroupDetailViewController == nil) {
+            // Return YES to indicate that we have handled the collapse by doing nothing; the secondary controller will be discarded.
+            return true
+        } else {
+            return false
+        }
+    }
+}
+
+// MARK: - UINavigationControllerDelegate
+extension SplitViewCoordinator: UINavigationControllerDelegate {
+    
+    func navigationController(_ navigationController: UINavigationController, didShow viewController: UIViewController, animated: Bool) {
+        
+        if viewController == masterTabBarController {
+            masterNavigationController.delegate = nil
+            
+            // For unknown reason, the navigation bar is not restored correctly by [popToViewController:animated:]
+            // when a ViewController has hidden it (see MXKAttachmentsViewController).
+            // Patch: restore navigation bar by default here.
+            masterNavigationController.isNavigationBarHidden = false
+
+            // Release the current selected item (room/contact/...).
+            masterTabBarController.releaseSelectedItem()
+
+            if let popToHomeViewControllerCompletion = self.popToHomeViewControllerCompletion {
+                let popToHomeViewControllerCompletion2: (() -> Void)? = popToHomeViewControllerCompletion
+                self.popToHomeViewControllerCompletion = nil
+
+                DispatchQueue.main.async {
+                    popToHomeViewControllerCompletion2?()
+                }
+            }
+        }
+        
+    }
+}

Riot/Modules/SplitView/SplitViewCoordinatorType.swift

@@ -0,0 +1,25 @@
+/*
+ Copyright 2018 New Vector Ltd
+ 
+ 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 Foundation
+
+/// `SplitViewCoordinatorType` is a protocol describing a Coordinator that handle split view navigation flow.
+protocol SplitViewCoordinatorType: Coordinator, Presentable {
+    
+    func popToHome(animated: Bool, completion: (() -> Void)?)
+    
+    func restorePlaceholderDetails()
+}