issue-919: fixed issue where view lifecycle functions were being called prematurely

CHANGELOG.md

+## 2.12.4
+
+* Updated to [Motion 1.2.3](https://github.com/CosmicMind/Motion/releases/tag/1.2.3).
+* [issue-919](https://github.com/CosmicMind/Material/issues/919): Fixed issue where lifecycle methods were being called on tab item view controllers prematurely.
+* [pr-923](https://github.com/CosmicMind/Material/pull/923): Merge PR that fixes [issue-919](https://github.com/CosmicMind/Material/issues/919).
+
 ## 2.12.3
 
 * [issue-907](https://github.com/CosmicMind/Material/issues/907): Fixed Layout ordering issues.

Material.podspec

 Pod::Spec.new do |s|
 	s.name = 'Material'
-	s.version = '2.12.3'
+	s.version = '2.12.4'
 	s.license = 'BSD-3-Clause'
 	s.summary = 'A UI/UX framework for creating beautiful applications.'
 	s.homepage = 'http://materialswift.com'

Motion @ 9d898243

-Subproject commit b56ec4be55f32f5e9341860bc8cef7fa1bdcc77d
+Subproject commit 9d898243db235f6f83e128bd632141bb36d73d84

Sources/iOS/TabsController.swift

@@ -201,15 +201,15 @@ fileprivate extension TabsController {
             return
         }
         
-        guard let tvcIndex = viewControllers.index(of: viewController) else {
+        let tvc = viewController
+        
+        guard let tvcIndex = viewControllers.index(of: tvc) else {
             return
         }
         
-        viewController.view.isHidden = false
-        viewController.view.frame = container.bounds
-        
         var isAuto = false
-        switch viewController.motionModalTransitionType {
+        
+        switch tvc.motionModalTransitionType {
         case .auto:
             isAuto = true
             viewController.motionModalTransitionType = fvcIndex < tvcIndex ? .slide(direction: .left) : .slide(direction: .right)
@@ -222,23 +222,28 @@ fileprivate extension TabsController {
         
         view.isUserInteractionEnabled = false
         
-        Motion.shared.transition(from: fvc, to: viewController, in: container) { [weak self, viewController = viewController, isAuto = isAuto, completion = completion] (isFinished) in
+        fvc.beginAppearanceTransition(false, animated: true)
+        
+        Motion.shared.transition(from: fvc, to: viewController, in: container) { [weak self, tvc = tvc, isAuto = isAuto, completion = completion] (isFinished) in
             guard let s = self else {
                 return
             }
-            
+
             if isAuto {
-                viewController.motionModalTransitionType = .auto
+                tvc.motionModalTransitionType = .auto
             }
-            
-            s.rootViewController = viewController
+
+            s.rootViewController = tvc
             s.view.isUserInteractionEnabled = true
+            
             s.removeViewController(viewController: fvc)
             
-            completion?(isFinished)
+            fvc.endAppearanceTransition()
             
+            completion?(isFinished)
+
             if isTriggeredByUserInteraction {
-                s.delegate?.tabsController?(tabsController: s, didSelect: viewController)
+                s.delegate?.tabsController?(tabsController: s, didSelect: tvc)
             }
         }
     }