Removed backing store that was mirroring uiviewcontroller childviewcontrollers, relying on childviewcontrollers only now

Author: Ian Outterside

IAOViewControllerStack/IAOViewControllerStack/IAOViewControllerStack/UIViewController+IAOUIViewControllerStack.h

@@ -20,6 +20,5 @@
 - (void)popToRootViewControllerAnimated:(BOOL)animated completion:(void(^)(void))success;
 
 - (UIViewController *)rootViewControllerForNavigationStack;
-- (NSMutableArray *)viewControllerStack;
 
 @end

IAOViewControllerStack/IAOViewControllerStack/IAOViewControllerStack/UIViewController+IAOUIViewControllerStack.m

@@ -10,7 +10,6 @@
 #import <objc/runtime.h>
 
 static char kIAOROOTVIEWCONTROLLER_IDENTIFIER;
-static char kIAOVIEWCONTROLLERSTACK_IDENTIFIER;
 
 @implementation UIViewController (IAOUIViewControllerStack)
 
@@ -22,24 +21,15 @@ - (void)pushViewController:(UIViewController *)controller animated:(BOOL)animate
 
     UIViewController *rootViewController = [self rootViewControllerForNavigationStack];
 
-    NSMutableArray *viewControllerStack = [rootViewController viewControllerStack];
-    
-    if (!viewControllerStack) {
-        viewControllerStack = [NSMutableArray arrayWithCapacity:1];
-        objc_setAssociatedObject(rootViewController, &kIAOVIEWCONTROLLERSTACK_IDENTIFIER, viewControllerStack, OBJC_ASSOCIATION_RETAIN);
-    }
-    
-    // Set the viewcontrollers root view controller property
     objc_setAssociatedObject(controller, &kIAOROOTVIEWCONTROLLER_IDENTIFIER, rootViewController, OBJC_ASSOCIATION_ASSIGN);
 
-    [rootViewController addChildViewController:controller];
-    
     BOOL previousClip = rootViewController.view.clipsToBounds;
     rootViewController.view.clipsToBounds = YES;
 
     // Transition
-    if ([viewControllerStack count] > 0) {
-        UIViewController *previousViewController = [viewControllerStack objectAtIndex:([viewControllerStack count] - 1)];
+    if ([rootViewController.childViewControllers count] > 0) {
+        UIViewController *previousViewController = [rootViewController.childViewControllers objectAtIndex:([rootViewController.childViewControllers count] - 1)];
+        [rootViewController addChildViewController:controller];
 
         if (animated) {
             controller.view.frame = CGRectMake(rootViewController.view.bounds.origin.x + rootViewController.view.bounds.size.width, rootViewController.view.bounds.origin.y, controller.view.frame.size.width, controller.view.frame.size.height);
@@ -58,8 +48,6 @@ - (void)pushViewController:(UIViewController *)controller animated:(BOOL)animate
         } completion:^(BOOL finished) {
             [controller didMoveToParentViewController:rootViewController];
 
-            // Add the viewcontroller to the stack
-            [viewControllerStack addObject:controller];
             rootViewController.view.clipsToBounds = previousClip;
 
             if (success) {
@@ -70,10 +58,6 @@ - (void)pushViewController:(UIViewController *)controller animated:(BOOL)animate
     else {
         void (^addBlock)(void) = ^{
             [controller didMoveToParentViewController:rootViewController];
-            
-            // Add the viewcontroller to the stack
-            [viewControllerStack addObject:controller];
-            
             rootViewController.view.clipsToBounds = previousClip;
 
             if (success) {
@@ -82,6 +66,7 @@ - (void)pushViewController:(UIViewController *)controller animated:(BOOL)animate
         };
 
         controller.view.frame = rootViewController.view.bounds;
+        [rootViewController addChildViewController:controller];
         [rootViewController.view addSubview:controller.view];
 
         if (animated) {
@@ -118,21 +103,19 @@ - (void)popViewControllerAnimated:(BOOL)animated completion:(void (^)(void))succ
         return;
     }
 
-    NSMutableArray *viewControllerStack = [rootViewController viewControllerStack];
-    
     BOOL previousClip = rootViewController.view.clipsToBounds;
     rootViewController.view.clipsToBounds = YES;
 
     // Cant pop if we have no children
-    if (!viewControllerStack || [viewControllerStack count] == 0) {
+    if ([rootViewController.childViewControllers count] == 0) {
         return;
     }
 
-    UIViewController *topViewController = [viewControllerStack objectAtIndex:([viewControllerStack count] - 1)];
+    UIViewController *topViewController = [rootViewController.childViewControllers objectAtIndex:([rootViewController.childViewControllers count] - 1)];
 
     // Move between top and next child
-    if ([viewControllerStack count] > 1) {
-        UIViewController *nextChildViewController = [viewControllerStack objectAtIndex:([viewControllerStack count] - 2)];
+    if ([rootViewController.childViewControllers count] > 1) {
+        UIViewController *nextChildViewController = [rootViewController.childViewControllers objectAtIndex:([rootViewController.childViewControllers count] - 2)];
 
         [topViewController willMoveToParentViewController:nil];
 
@@ -152,7 +135,6 @@ - (void)popViewControllerAnimated:(BOOL)animated completion:(void (^)(void))succ
 
         } completion:^(BOOL finished) {
             [topViewController removeFromParentViewController];
-            [viewControllerStack removeObject:topViewController];
             rootViewController.view.clipsToBounds = previousClip;
 
             if (success) {
@@ -165,11 +147,8 @@ - (void)popViewControllerAnimated:(BOOL)animated completion:(void (^)(void))succ
             [topViewController willMoveToParentViewController:nil];
             [topViewController.view removeFromSuperview];
             [topViewController removeFromParentViewController];
-            [viewControllerStack removeObject:topViewController];
             rootViewController.view.clipsToBounds = previousClip;
 
-            objc_setAssociatedObject(rootViewController, &kIAOVIEWCONTROLLERSTACK_IDENTIFIER, nil, OBJC_ASSOCIATION_RETAIN);
-            
             if (success) {
                 success();
             }
@@ -203,36 +182,29 @@ - (void)popToRootViewControllerAnimated:(BOOL)animated completion:(void (^)(void
         return;
     }
 
-    NSMutableArray *viewControllerStack = [rootViewController viewControllerStack];
-    
     BOOL previousClip = rootViewController.view.clipsToBounds;
     rootViewController.view.clipsToBounds = YES;
 
     // Cant pop if we have no children
-    if (!viewControllerStack || [viewControllerStack count] == 0) {
+    if ([rootViewController.childViewControllers count] == 0) {
         return;
     }
 
-    UIViewController *topViewController = [viewControllerStack objectAtIndex:([viewControllerStack count] - 1)];
-    [viewControllerStack removeObject:topViewController];
+    UIViewController *topViewController = [rootViewController.childViewControllers objectAtIndex:([rootViewController.childViewControllers count] - 1)];
 
-    while ([viewControllerStack count] > 0) {
-        UIViewController *controller = [viewControllerStack objectAtIndex:([viewControllerStack count] - 1)];
+    while ([rootViewController.childViewControllers count] > 1) {
+        UIViewController *controller = [rootViewController.childViewControllers objectAtIndex:([rootViewController.childViewControllers count] - 2)];
 
         [controller willMoveToParentViewController:nil];
         [controller removeFromParentViewController];
-        [viewControllerStack removeObject:controller];
     }
 
     void (^removeBlock)(void) = ^{
         [topViewController willMoveToParentViewController:nil];
         [topViewController.view removeFromSuperview];
         [topViewController removeFromParentViewController];
-        [viewControllerStack removeObject:topViewController];
         rootViewController.view.clipsToBounds = previousClip;
 
-        objc_setAssociatedObject(rootViewController, &kIAOVIEWCONTROLLERSTACK_IDENTIFIER, nil, OBJC_ASSOCIATION_RETAIN);
-        
         if (success) {
             success();
         }
@@ -263,14 +235,4 @@ - (UIViewController *)rootViewControllerForNavigationStack {
     }
 }
 
-- (NSMutableArray *)viewControllerStack {
-    UIViewController *rootViewController = [self rootViewControllerForNavigationStack];
-    
-    if (rootViewController != self) {
-        return nil;
-    }
-    
-    return (NSMutableArray *)objc_getAssociatedObject(self, &kIAOVIEWCONTROLLERSTACK_IDENTIFIER);
-}
-
 @end

IAOViewControllerStack/IAOViewControllerStack/TestViewController.m

@@ -49,29 +49,27 @@ - (BOOL)shouldAutorotateToInterfaceOrientation:(UIInterfaceOrientation)interface
 - (IBAction)addViewControllerPressed:(id)sender {
 
     UIViewController *rootViewController = [self rootViewControllerForNavigationStack];
-    NSArray *array = [rootViewController viewControllerStack];
-    
     TestViewController *testViewController = [[TestViewController alloc] initWithNibName:@"TestViewController" bundle:[NSBundle mainBundle]];
-    testViewController.title = [NSString stringWithFormat:@"%i", [array count]];
+    testViewController.title = [NSString stringWithFormat:@"%i", [rootViewController.childViewControllers count]];
 
     NSLog(@"Saving %@", testViewController.title);
 
     [self pushViewController:testViewController animated:YES completion:^{
-        NSLog(@"%@",[rootViewController viewControllerStack]);
+        NSLog(@"%@",[rootViewController childViewControllers]);
     }];
 }
 
 - (IBAction)removeViewControllerPressed:(id)sender {
     [self popViewControllerAnimated:YES completion:^{
         UIViewController *rootViewController = [self rootViewControllerForNavigationStack];
-        NSLog(@"%@",[rootViewController viewControllerStack]);
+        NSLog(@"%@",[rootViewController childViewControllers]);
     }];
 }
 
 - (IBAction)rootViewControllerPressed:(id)sender {
     [self popToRootViewControllerAnimated:YES completion:^{
         UIViewController *rootViewController = [self rootViewControllerForNavigationStack];
-        NSLog(@"%@",[rootViewController viewControllerStack]);
+        NSLog(@"%@",[rootViewController childViewControllers]);
     }];
 }