Use child view controller for loading

Tusker.xcodeproj/project.pbxproj

@@ -107,6 +107,8 @@
 		D6C693CF216125FC007D6A6D /* SilentActionPermissionTableViewCell.swift in Sources */ = {isa = PBXBuildFile; fileRef = D6C693CE216125FC007D6A6D /* SilentActionPermissionTableViewCell.swift */; };
 		D6C693EF216192C2007D6A6D /* TuskerNavigationDelegate.swift in Sources */ = {isa = PBXBuildFile; fileRef = D6C693EE216192C2007D6A6D /* TuskerNavigationDelegate.swift */; };
 		D6C693F92162E4DB007D6A6D /* StatusContentLabel.swift in Sources */ = {isa = PBXBuildFile; fileRef = D6C693F82162E4DB007D6A6D /* StatusContentLabel.swift */; };
+		D6C693FC2162FE6F007D6A6D /* LoadingViewController.swift in Sources */ = {isa = PBXBuildFile; fileRef = D6C693FB2162FE6F007D6A6D /* LoadingViewController.swift */; };
+		D6C693FE2162FEEA007D6A6D /* UIViewController+Children.swift in Sources */ = {isa = PBXBuildFile; fileRef = D6C693FD2162FEEA007D6A6D /* UIViewController+Children.swift */; };
 		D6C94D852139DFD800CB5196 /* LargeImage.storyboard in Resources */ = {isa = PBXBuildFile; fileRef = D6C94D842139DFD800CB5196 /* LargeImage.storyboard */; };
 		D6C94D872139E62700CB5196 /* LargeImageViewController.swift in Sources */ = {isa = PBXBuildFile; fileRef = D6C94D862139E62700CB5196 /* LargeImageViewController.swift */; };
 		D6C94D892139E6EC00CB5196 /* AttachmentView.swift in Sources */ = {isa = PBXBuildFile; fileRef = D6C94D882139E6EC00CB5196 /* AttachmentView.swift */; };
@@ -285,6 +287,8 @@
 		D6C693CE216125FC007D6A6D /* SilentActionPermissionTableViewCell.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = SilentActionPermissionTableViewCell.swift; sourceTree = "<group>"; };
 		D6C693EE216192C2007D6A6D /* TuskerNavigationDelegate.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = TuskerNavigationDelegate.swift; sourceTree = "<group>"; };
 		D6C693F82162E4DB007D6A6D /* StatusContentLabel.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = StatusContentLabel.swift; sourceTree = "<group>"; };
+		D6C693FB2162FE6F007D6A6D /* LoadingViewController.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = LoadingViewController.swift; sourceTree = "<group>"; };
+		D6C693FD2162FEEA007D6A6D /* UIViewController+Children.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = "UIViewController+Children.swift"; sourceTree = "<group>"; };
 		D6C94D842139DFD800CB5196 /* LargeImage.storyboard */ = {isa = PBXFileReference; lastKnownFileType = file.storyboard; path = LargeImage.storyboard; sourceTree = "<group>"; };
 		D6C94D862139E62700CB5196 /* LargeImageViewController.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = LargeImageViewController.swift; sourceTree = "<group>"; };
 		D6C94D882139E6EC00CB5196 /* AttachmentView.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = AttachmentView.swift; sourceTree = "<group>"; };
@@ -456,6 +460,7 @@
 		D641C780213DD7C4004B4513 /* Screens */ = {
 			isa = PBXGroup;
 			children = (
+				D6C693FA2162FE5D007D6A6D /* Utilities */,
 				D641C782213DD7F0004B4513 /* Main */,
 				D641C783213DD7FE004B4513 /* Onboarding */,
 				D641C781213DD7DD004B4513 /* Timeline */,
@@ -664,6 +669,15 @@
 			path = "Silent Action Permissions";
 			sourceTree = "<group>";
 		};
+		D6C693FA2162FE5D007D6A6D /* Utilities */ = {
+			isa = PBXGroup;
+			children = (
+				D6C693FB2162FE6F007D6A6D /* LoadingViewController.swift */,
+				D6C693FD2162FEEA007D6A6D /* UIViewController+Children.swift */,
+			);
+			path = Utilities;
+			sourceTree = "<group>";
+		};
 		D6D4DDC3212518A000E1C4BB = {
 			isa = PBXGroup;
 			children = (
@@ -1086,10 +1100,12 @@
 				D6C693CA2161253F007D6A6D /* SilentActionPermissionsTableViewController.swift in Sources */,
 				D6333B372137838300CE884A /* AttributedString+Trim.swift in Sources */,
 				D641C777213CAA9E004B4513 /* ActionNotificationTableViewCell.swift in Sources */,
+				D6C693FE2162FEEA007D6A6D /* UIViewController+Children.swift in Sources */,
 				D64D0AB12128D9AE005A6F37 /* OnboardingViewController.swift in Sources */,
 				D663626821360E2C00C9CBA2 /* PreferencesTableViewController.swift in Sources */,
 				D64F80E2215875CC00BEF393 /* XCBActionType.swift in Sources */,
 				D66362752137068A00C9CBA2 /* Visibility+Helpers.swift in Sources */,
+				D6C693FC2162FE6F007D6A6D /* LoadingViewController.swift in Sources */,
 				D646C95A213B5D0500269FB5 /* LargeImageInteractionController.swift in Sources */,
 				D6F953EC212519E700CF0F2B /* TimelineTableViewController.swift in Sources */,
 				D663626A2136163000C9CBA2 /* PreferencesAdaptive.swift in Sources */,

Tusker/Screens/Profile/ProfileTableViewController.swift

@@ -43,13 +43,8 @@ class ProfileTableViewController: UITableViewController, PreferencesAdaptive {
         if MastodonCache.account(for: accountID) != nil {
             updateAccountUI()
         } else {
-            let activityIndicator = UIActivityIndicatorView(style: .whiteLarge)
+            let loadingVC = LoadingViewController()
-            activityIndicator.color = .darkGray
+            add(loadingVC)
-            activityIndicator.startAnimating()
-            activityIndicator.translatesAutoresizingMaskIntoConstraints = false
-            view.addSubview(activityIndicator)
-            activityIndicator.centerXAnchor.constraint(equalTo: view.safeAreaLayoutGuide.centerXAnchor)
-            activityIndicator.centerYAnchor.constraint(equalTo: view.safeAreaLayoutGuide.centerYAnchor)
             MastodonCache.account(for: accountID) { (account) in
                 guard account != nil else {
                     let alert = UIAlertController(title: "Something Went Wrong", message: "Couldn't load the selected account", preferredStyle: .alert)
@@ -62,11 +57,12 @@ class ProfileTableViewController: UITableViewController, PreferencesAdaptive {
                     return
                 }
                 DispatchQueue.main.async {
-                    activityIndicator.removeFromSuperview()
+                    loadingVC.remove()
                     self.updateAccountUI()
                     self.tableView.reloadData()
                 }
             }
+            
         }
     }
     

Tusker/Screens/Utilities/LoadingViewController.swift

@@ -0,0 +1,38 @@
+//
+//  LoadingViewController.swift
+//  Tusker
+//
+//  Created by Shadowfacts on 10/1/18.
+//  Copyright © 2018 Shadowfacts. All rights reserved.
+//
+
+import UIKit
+
+// Based on John Sundell's example: https://www.swiftbysundell.com/posts/using-child-view-controllers-as-plugins-in-swift
+class LoadingViewController: UIViewController {
+
+    private var activityIndicator: UIActivityIndicatorView!
+    
+    override func viewDidLoad() {
+        super.viewDidLoad()
+        
+        activityIndicator = UIActivityIndicatorView(style: .whiteLarge)
+        activityIndicator.color = .darkGray
+        activityIndicator.translatesAutoresizingMaskIntoConstraints = false
+        
+        view.addSubview(activityIndicator)
+        
+        activityIndicator.centerXAnchor.constraint(equalTo: view.safeAreaLayoutGuide.centerXAnchor).isActive = true
+        activityIndicator.centerYAnchor.constraint(equalTo: view.safeAreaLayoutGuide.centerYAnchor).isActive = true
+    }
+    
+    override func viewWillAppear(_ animated: Bool) {
+        super.viewWillAppear(animated)
+        
+        // 0.5s delay so indicator is not shown if data loads very quickly
+        DispatchQueue.main.asyncAfter(deadline: .now() + 0.5) { [weak self] in
+            self?.activityIndicator.startAnimating()
+        }
+    }
+
+}

Tusker/Screens/Utilities/UIViewController+Children.swift

@@ -0,0 +1,25 @@
+//
+//  UIViewController+Children.swift
+//  Tusker
+//
+//  Created by Shadowfacts on 10/1/18.
+//  Copyright © 2018 Shadowfacts. All rights reserved.
+//
+
+import UIKit
+
+extension UIViewController {
+    func add(_ child: UIViewController) {
+        addChild(child)
+        view.addSubview(child.view)
+        child.didMove(toParent: self)
+    }
+    
+    func remove() {
+        guard parent != nil else { return }
+        
+        willMove(toParent: nil)
+        removeFromParent()
+        view.removeFromSuperview()
+    }
+}