Bottom tabs attach mode support on iOS (#5733)

Add iOS support for `bottomTabs.attachMode`.
This property controls when BottomTabs children are attached to hierarchy and when their React views are created.

By default, RNN attaches all children at the same time which might impact loading time as a few screens are instantiated at once.
Using `afterInitialTab` or `onSwitchToTab` generally leads to improved start up time.

lib/ios/BottomTabsAfterInitialTabAttacher.h

+#import "BottomTabsBaseAttacher.h"
+
+@interface BottomTabsAfterInitialTabAttacher : BottomTabsBaseAttacher
+
+@end

lib/ios/BottomTabsAfterInitialTabAttacher.m

+#import "BottomTabsAfterInitialTabAttacher.h"
+#import "UITabBarController+RNNUtils.h"
+
+@implementation BottomTabsAfterInitialTabAttacher
+
+- (void)attach:(UITabBarController *)bottomTabsController {
+    [bottomTabsController.selectedViewController setReactViewReadyCallback:^{
+        [bottomTabsController readyForPresentation];
+        for (UIViewController* viewController in bottomTabsController.deselectedViewControllers) {
+            [viewController render];
+        }
+    }];
+    
+    [bottomTabsController.selectedViewController render];
+}
+
+@end

lib/ios/BottomTabsAttachMode.h

+#import "Text.h"
+
+typedef NS_ENUM(NSInteger, AttachMode) {
+    BottomTabsAttachModeTogether = 0,
+    BottomTabsAttachModeAfterInitialTab,
+    BottomTabsAttachModeOnSwitchToTab
+};
+
+@interface BottomTabsAttachMode : Text
+
+- (AttachMode)get;
+
+- (AttachMode)getWithDefaultValue:(id)defaultValue;
+
+@end

lib/ios/BottomTabsAttachMode.m

+#import "BottomTabsAttachMode.h"
+#import <React/RCTConvert.h>
+
+@implementation BottomTabsAttachMode
+
+- (AttachMode)get {
+    return [self.class AttachMode:[super get]];
+}
+
+- (AttachMode)getWithDefaultValue:(id)defaultValue {
+    return [self.class AttachMode:[super getWithDefaultValue:defaultValue]];
+}
+
+RCT_ENUM_CONVERTER(AttachMode,
+(@{@"together": @(BottomTabsAttachModeTogether),
+   @"afterInitialTab": @(BottomTabsAttachModeAfterInitialTab),
+   @"onSwitchToTab": @(BottomTabsAttachModeOnSwitchToTab)
+}), BottomTabsAttachModeTogether, integerValue)
+
+
+@end

lib/ios/BottomTabsAttachModeFactory.h

+#import <Foundation/Foundation.h>
+#import "RNNNavigationOptions.h"
+#import "BottomTabsBaseAttacher.h"
+
+@interface BottomTabsAttachModeFactory : NSObject
+
+- (instancetype)initWithDefaultOptions:(RNNNavigationOptions *)defaultOptions;
+
+- (BottomTabsBaseAttacher *)fromOptions:(RNNNavigationOptions *)options;
+
+@property (nonatomic, retain) RNNNavigationOptions* defaultOptions;
+
+@end

lib/ios/BottomTabsAttachModeFactory.m

+#import "BottomTabsAttachModeFactory.h"
+#import "BottomTabsTogetherAttacher.h"
+#import "BottomTabsOnSwitchToTabAttacher.h"
+#import "BottomTabsAfterInitialTabAttacher.h"
+
+@implementation BottomTabsAttachModeFactory
+
+- (instancetype)initWithDefaultOptions:(RNNNavigationOptions *)defaultOptions {
+	self = [super init];
+	_defaultOptions = defaultOptions;
+	return self;
+}
+
+- (BottomTabsBaseAttacher *)fromOptions:(RNNNavigationOptions *)options {
+    AttachMode attachMode = [[options withDefault:_defaultOptions].bottomTabs.tabsAttachMode getWithDefaultValue:@"together"];
+	switch (attachMode) {
+        case BottomTabsAttachModeAfterInitialTab: {
+            return [BottomTabsAfterInitialTabAttacher new];
+        }
+        case BottomTabsAttachModeOnSwitchToTab: {
+            return [BottomTabsOnSwitchToTabAttacher new];
+        }
+        default:
+            return [BottomTabsTogetherAttacher new];
+            break;
+    }
+}
+
+@end

lib/ios/BottomTabsBaseAttacher.h

+#import <Foundation/Foundation.h>
+#import "UIViewController+LayoutProtocol.h"
+
+@interface BottomTabsBaseAttacher : NSObject
+
+- (void)attach:(UITabBarController *)bottomTabsController;
+
+@end

lib/ios/BottomTabsBaseAttacher.m

+#import "BottomTabsBaseAttacher.h"
+
+@implementation BottomTabsBaseAttacher
+
+- (void)attach:(UITabBarController *)bottomTabsController {
+    
+}
+
+@end

lib/ios/BottomTabsOnSwitchToTabAttacher.h

+#import "BottomTabsBaseAttacher.h"
+
+@interface BottomTabsOnSwitchToTabAttacher : BottomTabsBaseAttacher
+
+@end

lib/ios/BottomTabsOnSwitchToTabAttacher.m

+#import "BottomTabsOnSwitchToTabAttacher.h"
+
+@implementation BottomTabsOnSwitchToTabAttacher
+
+- (void)attach:(UITabBarController *)bottomTabsController {
+    [bottomTabsController.selectedViewController setReactViewReadyCallback:^{
+        [bottomTabsController readyForPresentation];
+    }];
+    
+    [bottomTabsController.selectedViewController render];
+}
+
+@end

lib/ios/BottomTabsTogetherAttacher.h

+#import "BottomTabsBaseAttacher.h"
+
+@interface BottomTabsTogetherAttacher : BottomTabsBaseAttacher
+
+@end

lib/ios/BottomTabsTogetherAttacher.m

+#import "BottomTabsTogetherAttacher.h"
+
+@implementation BottomTabsTogetherAttacher
+
+- (void)attach:(UITabBarController *)bottomTabsController {
+    for (UIViewController* childViewController in bottomTabsController.childViewControllers) {
+        [childViewController render];
+    }
+    
+    [bottomTabsController readyForPresentation];
+}
+
+@end

lib/ios/RNNBottomTabsController.h

 #import "RNNEventEmitter.h"
 #import "RNNBottomTabsPresenter.h"
 #import "UIViewController+LayoutProtocol.h"
+#import "BottomTabsBaseAttacher.h"
 
 @interface RNNBottomTabsController : UITabBarController <RNNLayoutProtocol, UITabBarControllerDelegate>
 
+- (instancetype)initWithLayoutInfo:(RNNLayoutInfo *)layoutInfo
+                           creator:(id<RNNComponentViewCreator>)creator
+                           options:(RNNNavigationOptions *)options
+                    defaultOptions:(RNNNavigationOptions *)defaultOptions
+                         presenter:(RNNBasePresenter *)presenter
+                      eventEmitter:(RNNEventEmitter *)eventEmitter
+              childViewControllers:(NSArray *)childViewControllers
+                bottomTabsAttacher:(BottomTabsBaseAttacher *)bottomTabsAttacher;
+
 - (void)setSelectedIndexByComponentID:(NSString *)componentID;
 
 @end

lib/ios/RNNBottomTabsController.m

 #import "RNNBottomTabsController.h"
+#import "UITabBarController+RNNUtils.h"
 
 @implementation RNNBottomTabsController {
 	NSUInteger _currentTabIndex;
+    BottomTabsBaseAttacher* _bottomTabsAttacher;
+}
+
+- (instancetype)initWithLayoutInfo:(RNNLayoutInfo *)layoutInfo
+                           creator:(id<RNNComponentViewCreator>)creator
+                           options:(RNNNavigationOptions *)options
+                    defaultOptions:(RNNNavigationOptions *)defaultOptions
+                         presenter:(RNNBasePresenter *)presenter
+                      eventEmitter:(RNNEventEmitter *)eventEmitter
+              childViewControllers:(NSArray *)childViewControllers
+                bottomTabsAttacher:(BottomTabsBaseAttacher *)bottomTabsAttacher {
+    self = [super initWithLayoutInfo:layoutInfo creator:creator options:options defaultOptions:defaultOptions presenter:presenter eventEmitter:eventEmitter childViewControllers:childViewControllers];
+    _bottomTabsAttacher = bottomTabsAttacher;
+    return self;
 }
 
 - (id<UITabBarControllerDelegate>)delegate {
 	return self;
 }
 
+- (void)render {
+    [_bottomTabsAttacher attach:self];
+}
+
 - (void)viewDidLayoutSubviews {
 	[self.presenter viewDidLayoutSubviews];
 }

lib/ios/RNNBottomTabsOptions.h

 #import "RNNOptions.h"
+#import "BottomTabsAttachMode.h"
 
 @interface RNNBottomTabsOptions : RNNOptions
 
 @property (nonatomic, strong) Text* barStyle;
 @property (nonatomic, strong) Text* fontFamily;
 @property (nonatomic, strong) Text* titleDisplayMode;
+@property (nonatomic, strong) BottomTabsAttachMode* tabsAttachMode;
 
 @end

lib/ios/RNNBottomTabsOptions.m

 	self.hideShadow = [BoolParser parse:dict key:@"hideShadow"];
 	self.backgroundColor = [ColorParser parse:dict key:@"backgroundColor"];
 	self.fontSize = [NumberParser parse:dict key:@"fontSize"];
-	
 	self.testID = [TextParser parse:dict key:@"testID"];
 	self.currentTabId = [TextParser parse:dict key:@"currentTabId"];
 	self.barStyle = [TextParser parse:dict key:@"barStyle"];
 	self.fontFamily = [TextParser parse:dict key:@"fontFamily"];
 	self.titleDisplayMode = [TextParser parse:dict key:@"titleDisplayMode"];
+    self.tabsAttachMode = [TextParser parse:dict key:@"tabsAttachMode"];
 	
 	return self;
 }

lib/ios/RNNBridgeManager.m

 
 	id<RNNComponentViewCreator> rootViewCreator = [[RNNReactRootViewCreator alloc] initWithBridge:bridge];
 	_componentRegistry = [[RNNReactComponentRegistry alloc] initWithCreator:rootViewCreator];
-	RNNControllerFactory *controllerFactory = [[RNNControllerFactory alloc] initWithRootViewCreator:rootViewCreator eventEmitter:eventEmitter store:_store componentRegistry:_componentRegistry andBridge:bridge];
+	RNNControllerFactory *controllerFactory = [[RNNControllerFactory alloc] initWithRootViewCreator:rootViewCreator eventEmitter:eventEmitter store:_store componentRegistry:_componentRegistry andBridge:bridge bottomTabsAttachModeFactory:[BottomTabsAttachModeFactory new]];
 
 	_commandsHandler = [[RNNCommandsHandler alloc] initWithControllerFactory:controllerFactory eventEmitter:eventEmitter stackManager:[RNNNavigationStackManager new] modalManager:_modalManager overlayManager:_overlayManager mainWindow:_mainWindow];
 	RNNBridgeModule *bridgeModule = [[RNNBridgeModule alloc] initWithCommandsHandler:_commandsHandler];

lib/ios/RNNCommandsHandler.m

 	[_modalManager dismissAllModalsAnimated:NO completion:nil];
 	
 	UIViewController *vc = [_controllerFactory createLayout:layout[@"root"]];
-	
-	[vc renderTreeAndWait:[vc.resolveOptions.animations.setRoot.waitForRender getWithDefaultValue:NO] perform:^{
-		_mainWindow.rootViewController = vc;
-		[_eventEmitter sendOnNavigationCommandCompletion:setRoot commandId:commandId params:@{@"layout": layout}];
-		completion() ;
-	}];
+    vc.waitForRender = [vc.resolveOptionsWithDefault.animations.setRoot.waitForRender getWithDefaultValue:NO];
+    
+    [vc setReactViewReadyCallback:^{
+        _mainWindow.rootViewController = vc;
+        [_eventEmitter sendOnNavigationCommandCompletion:setRoot commandId:commandId params:@{@"layout": layout}];
+        completion();
+    }];
+    
+	[vc render];
 }
 
 - (void)mergeOptions:(NSString*)componentId options:(NSDictionary*)mergeOptions completion:(RNNTransitionCompletionBlock)completion {
 	UIViewController *newVc = [_controllerFactory createLayout:layout];
 	UIViewController *fromVC = [RNNLayoutManager findComponentForId:componentId];
 	
-	if ([[newVc.resolveOptions.preview.reactTag getWithDefaultValue:@(0)] floatValue] > 0) {
+	if ([[newVc.resolveOptionsWithDefault.preview.reactTag getWithDefaultValue:@(0)] floatValue] > 0) {
 		UIViewController* vc = [RNNLayoutManager findComponentForId:componentId];
 		
 		if([vc isKindOfClass:[RNNComponentViewController class]]) {
 			RNNComponentViewController* rootVc = (RNNComponentViewController*)vc;
 			rootVc.previewController = newVc;
-			[newVc renderTreeAndWait:NO perform:nil];
+			[newVc render];
 			
 			rootVc.previewCallback = ^(UIViewController *vcc) {
 				RNNComponentViewController* rvc  = (RNNComponentViewController*)vcc;
 				[self->_eventEmitter sendOnPreviewCompleted:componentId previewComponentId:newVc.layoutInfo.componentId];
-				if ([newVc.resolveOptions.preview.commit getWithDefaultValue:NO]) {
+				if ([newVc.resolveOptionsWithDefault.preview.commit getWithDefaultValue:NO]) {
 					[CATransaction begin];
 					[CATransaction setCompletionBlock:^{
 						[self->_eventEmitter sendOnNavigationCommandCompletion:push commandId:commandId params:@{@"componentId": componentId}];
 			
 			CGSize size = CGSizeMake(rootVc.view.frame.size.width, rootVc.view.frame.size.height);
 			
-			if (newVc.resolveOptions.preview.width.hasValue) {
-				size.width = [newVc.resolveOptions.preview.width.get floatValue];
+			if (newVc.resolveOptionsWithDefault.preview.width.hasValue) {
+				size.width = [newVc.resolveOptionsWithDefault.preview.width.get floatValue];
 			}
 			
-			if (newVc.resolveOptions.preview.height.hasValue) {
-				size.height = [newVc.resolveOptions.preview.height.get floatValue];
+			if (newVc.resolveOptionsWithDefault.preview.height.hasValue) {
+				size.height = [newVc.resolveOptionsWithDefault.preview.height.get floatValue];
 			}
 			
-			if (newVc.resolveOptions.preview.width.hasValue || newVc.resolveOptions.preview.height.hasValue) {
+			if (newVc.resolveOptionsWithDefault.preview.width.hasValue || newVc.resolveOptionsWithDefault.preview.height.hasValue) {
 				newVc.preferredContentSize = size;
 			}
 			
 			RCTExecuteOnMainQueue(^{
-				UIView *view = [[ReactNativeNavigation getBridge].uiManager viewForReactTag:newVc.resolveOptions.preview.reactTag.get];
+				UIView *view = [[ReactNativeNavigation getBridge].uiManager viewForReactTag:newVc.resolveOptionsWithDefault.preview.reactTag.get];
 				[rootVc registerForPreviewingWithDelegate:(id)rootVc sourceView:view];
 			});
 		}
 	} else {
-		id animationDelegate = (newVc.resolveOptions.animations.push.hasCustomAnimation || newVc.resolveOptions.customTransition.animations) ? newVc : nil;
-		[newVc renderTreeAndWait:([newVc.resolveOptions.animations.push.waitForRender getWithDefaultValue:NO] || animationDelegate) perform:^{
-			[_stackManager push:newVc onTop:fromVC animated:[newVc.resolveOptions.animations.push.enable getWithDefaultValue:YES] animationDelegate:animationDelegate completion:^{
-				[_eventEmitter sendOnNavigationCommandCompletion:push commandId:commandId params:@{@"componentId": componentId}];
-				completion();
-			} rejection:rejection];
-		}];
+		id animationDelegate = (newVc.resolveOptionsWithDefault.animations.push.hasCustomAnimation || newVc.resolveOptionsWithDefault.customTransition.animations) ? newVc : nil;
+        newVc.waitForRender = ([newVc.resolveOptionsWithDefault.animations.push.waitForRender getWithDefaultValue:NO] || animationDelegate);
+        [newVc setReactViewReadyCallback:^{
+            [_stackManager push:newVc onTop:fromVC animated:[newVc.resolveOptionsWithDefault.animations.push.enable getWithDefaultValue:YES] animationDelegate:animationDelegate completion:^{
+                [_eventEmitter sendOnNavigationCommandCompletion:push commandId:commandId params:@{@"componentId": componentId}];
+                completion();
+            } rejection:rejection];
+        }];
+        
+        [newVc render];
 	}
 }
 
 	NSArray<UIViewController *> *childViewControllers = [_controllerFactory createChildrenLayout:children];
 	for (UIViewController<RNNLayoutProtocol>* viewController in childViewControllers) {
 		if (![viewController isEqual:childViewControllers.lastObject]) {
-			[viewController renderTreeAndWait:NO perform:nil];
+			[viewController render];
 		}
 	}
 	UIViewController *newVC = childViewControllers.lastObject;
 	UIViewController *fromVC = [RNNLayoutManager findComponentForId:componentId];
-	RNNNavigationOptions* options = newVC.resolveOptions;
+	RNNNavigationOptions* options = newVC.resolveOptionsWithDefault;
 	__weak typeof(RNNEventEmitter*) weakEventEmitter = _eventEmitter;
 
-	[newVC renderTreeAndWait:([options.animations.setStackRoot.waitForRender getWithDefaultValue:NO]) perform:^{
-		[_stackManager setStackChildren:childViewControllers fromViewController:fromVC animated:[options.animations.setStackRoot.enable getWithDefaultValue:YES] completion:^{
-			[weakEventEmitter sendOnNavigationCommandCompletion:setStackRoot commandId:commandId params:@{@"componentId": componentId}];
-			completion();
-		} rejection:rejection];
-	}]; 
+    newVC.waitForRender = ([options.animations.setStackRoot.waitForRender getWithDefaultValue:NO]);
+    [newVC setReactViewReadyCallback:^{
+        [self->_stackManager setStackChildren:childViewControllers fromViewController:fromVC animated:[options.animations.setStackRoot.enable getWithDefaultValue:YES] completion:^{
+            [weakEventEmitter sendOnNavigationCommandCompletion:setStackRoot commandId:commandId params:@{@"componentId": componentId}];
+            completion();
+        } rejection:rejection];
+    }];
+
+    [newVC render];
 }
 
 - (void)pop:(NSString*)componentId commandId:(NSString*)commandId mergeOptions:(NSDictionary*)mergeOptions completion:(RNNTransitionCompletionBlock)completion rejection:(RCTPromiseRejectBlock)rejection {
 	UINavigationController *nvc = vc.navigationController;
 	
 	if ([nvc topViewController] == vc) {
-		if (vc.resolveOptions.animations.pop) {
+		if (vc.resolveOptionsWithDefault.animations.pop) {
 			nvc.delegate = vc;
 		} else {
 			nvc.delegate = nil;
 	} else {
 		NSMutableArray * vcs = nvc.viewControllers.mutableCopy;
 		[vcs removeObject:vc];
-		[nvc setViewControllers:vcs animated:[vc.resolveOptions.animations.pop.enable getWithDefaultValue:YES]];
+		[nvc setViewControllers:vcs animated:[vc.resolveOptionsWithDefault.animations.pop.enable getWithDefaultValue:YES]];
 	}
 	
-	[_stackManager pop:vc animated:[vc.resolveOptions.animations.pop.enable getWithDefaultValue:YES] completion:^{
+	[_stackManager pop:vc animated:[vc.resolveOptionsWithDefault.animations.pop.enable getWithDefaultValue:YES] completion:^{
 		[_eventEmitter sendOnNavigationCommandCompletion:pop commandId:commandId params:@{@"componentId": componentId}];
 		completion();
 	} rejection:rejection];
 	RNNNavigationOptions *options = [[RNNNavigationOptions alloc] initWithDict:mergeOptions];
 	[vc overrideOptions:options];
 	
-	[_stackManager popTo:vc animated:[vc.resolveOptions.animations.pop.enable getWithDefaultValue:YES] completion:^(NSArray *poppedViewControllers) {
+	[_stackManager popTo:vc animated:[vc.resolveOptionsWithDefault.animations.pop.enable getWithDefaultValue:YES] completion:^(NSArray *poppedViewControllers) {
 		[_eventEmitter sendOnNavigationCommandCompletion:popTo commandId:commandId params:@{@"componentId": componentId}];
 		completion();
 	} rejection:rejection];
 		completion();
 	}];
 	
-	[_stackManager popToRoot:vc animated:[vc.resolveOptions.animations.pop.enable getWithDefaultValue:YES] completion:^(NSArray *poppedViewControllers) {
+	[_stackManager popToRoot:vc animated:[vc.resolveOptionsWithDefault.animations.pop.enable getWithDefaultValue:YES] completion:^(NSArray *poppedViewControllers) {
 		
 	} rejection:^(NSString *code, NSString *message, NSError *error) {
 		
 	
 	UIViewController *newVc = [_controllerFactory createLayout:layout];
 	
-	[newVc renderTreeAndWait:[newVc.resolveOptions.animations.showModal.waitForRender getWithDefaultValue:NO] perform:^{
-		[_modalManager showModal:newVc animated:[newVc.resolveOptions.animations.showModal.enable getWithDefaultValue:YES] hasCustomAnimation:newVc.resolveOptions.animations.showModal.hasCustomAnimation completion:^(NSString *componentId) {
-			[_eventEmitter sendOnNavigationCommandCompletion:showModal commandId:commandId params:@{@"layout": layout}];
-			completion(newVc.layoutInfo.componentId);
-		}];
-	}];
+    newVc.waitForRender = [newVc.resolveOptionsWithDefault.animations.showModal.waitForRender getWithDefaultValue:NO];
+    [newVc setReactViewReadyCallback:^{
+        [_modalManager showModal:newVc animated:[newVc.resolveOptionsWithDefault.animations.showModal.enable getWithDefaultValue:YES] hasCustomAnimation:newVc.resolveOptionsWithDefault.animations.showModal.hasCustomAnimation completion:^(NSString *componentId) {
+            [self->_eventEmitter sendOnNavigationCommandCompletion:showModal commandId:commandId params:@{@"layout": layout}];
+            completion(newVc.layoutInfo.componentId);
+        }];
+    }];
+	[newVc render];
 }
 
 - (void)dismissModal:(NSString*)componentId commandId:(NSString*)commandId mergeOptions:(NSDictionary *)mergeOptions completion:(RNNTransitionCompletionBlock)completion rejection:(RNNTransitionRejectionBlock)reject {
 	
 	[CATransaction begin];
 	[CATransaction setCompletionBlock:^{
-		[_eventEmitter sendOnNavigationCommandCompletion:dismissModal commandId:commandId params:@{@"componentId": componentId}];
+        [self->_eventEmitter sendOnNavigationCommandCompletion:dismissModal commandId:commandId params:@{@"componentId": componentId}];
 	}];
 	
 	[_modalManager dismissModal:modalToDismiss completion:completion];
 	[self assertReady];
 	
 	UIViewController* overlayVC = [_controllerFactory createLayout:layout];
-	[overlayVC renderTreeAndWait:NO perform:^{
-		UIWindow* overlayWindow = [[RNNOverlayWindow alloc] initWithFrame:[[UIScreen mainScreen] bounds]];
-		overlayWindow.rootViewController = overlayVC;
-		if ([overlayVC.resolveOptions.overlay.handleKeyboardEvents getWithDefaultValue:NO]) {
-			[_overlayManager showOverlayWindowAsKeyWindow:overlayWindow];
-		} else {
-			[_overlayManager showOverlayWindow:overlayWindow];
-		}
-		
-		[_eventEmitter sendOnNavigationCommandCompletion:showOverlay commandId:commandId params:@{@"layout": layout}];
-		completion();
-	}];
+    [overlayVC setReactViewReadyCallback:^{UIWindow* overlayWindow = [[RNNOverlayWindow alloc] initWithFrame:[[UIScreen mainScreen] bounds]];
+        overlayWindow.rootViewController = overlayVC;
+        if ([overlayVC.resolveOptionsWithDefault.overlay.handleKeyboardEvents getWithDefaultValue:NO]) {
+            [self->_overlayManager showOverlayWindowAsKeyWindow:overlayWindow];
+        } else {
+            [self->_overlayManager showOverlayWindow:overlayWindow];
+        }
+        
+        [self->_eventEmitter sendOnNavigationCommandCompletion:showOverlay commandId:commandId params:@{@"layout": layout}];
+        completion();
+        
+    }];
+    
+    [overlayVC render];
 }
 
 - (void)dismissOverlay:(NSString*)componentId commandId:(NSString*)commandId completion:(RNNTransitionCompletionBlock)completion rejection:(RNNTransitionRejectionBlock)reject {

lib/ios/RNNComponentViewController.h

 
 typedef void (^PreviewCallback)(UIViewController *vc);
 
-@interface RNNComponentViewController : UIViewController	<RNNLayoutProtocol, UIViewControllerPreviewingDelegate, UISearchResultsUpdating, UISearchBarDelegate, UINavigationControllerDelegate, UISplitViewControllerDelegate>
+@interface RNNComponentViewController : UIViewController <RNNLayoutProtocol, UIViewControllerPreviewingDelegate, UISearchResultsUpdating, UISearchBarDelegate, UINavigationControllerDelegate, UISplitViewControllerDelegate>
 
 @property (nonatomic, strong) RNNEventEmitter *eventEmitter;
 @property (nonatomic, retain) RNNLayoutInfo* layoutInfo;
 						   options:(RNNNavigationOptions *)options
 					defaultOptions:(RNNNavigationOptions *)defaultOptions;
 
-- (instancetype)initExternalComponentWithLayoutInfo:(RNNLayoutInfo *)layoutInfo
-									   eventEmitter:(RNNEventEmitter*)eventEmitter
-										  presenter:(RNNComponentPresenter *)presenter
-											options:(RNNNavigationOptions *)options
-									 defaultOptions:(RNNNavigationOptions *)defaultOptions;
-
-- (BOOL)isExternalViewController;
-
 - (void)onButtonPress:(RNNUIBarButtonItem *)barButtonItem;
 
-- (void)bindViewController:(UIViewController *)viewController;
-
 @end

lib/ios/RNNComponentViewController.m

 	return self;
 }
 
-- (instancetype)initExternalComponentWithLayoutInfo:(RNNLayoutInfo *)layoutInfo eventEmitter:(RNNEventEmitter *)eventEmitter presenter:(RNNComponentPresenter *)presenter options:(RNNNavigationOptions *)options defaultOptions:(RNNNavigationOptions *)defaultOptions {
-	self = [self initWithLayoutInfo:layoutInfo rootViewCreator:nil eventEmitter:eventEmitter presenter:presenter options:options defaultOptions:defaultOptions];
-	return self;
-}
-
-- (void)bindViewController:(UIViewController *)viewController {
-	[self addChildViewController:viewController];
-	[self.view addSubview:viewController.view];
-	[viewController didMoveToParentViewController:self];
-}
-
 - (void)setDefaultOptions:(RNNNavigationOptions *)defaultOptions {
     _defaultOptions = defaultOptions;
 	[_presenter setDefaultOptions:defaultOptions];
 	[self.options overrideOptions:options];
 }
 
-- (void)viewWillAppear:(BOOL)animated{
+- (void)viewWillAppear:(BOOL)animated {
 	[super viewWillAppear:animated];
-	
 	[_presenter applyOptions:self.resolveOptions];
-	[_presenter renderComponents:self.resolveOptions perform:nil];
-	
 	[self.parentViewController onChildWillAppear];
 }
 
 	[self.eventEmitter sendComponentDidDisappear:self.layoutInfo.componentId componentName:self.layoutInfo.name];
 }
 
-- (void)renderTreeAndWait:(BOOL)wait perform:(RNNReactViewReadyCompletionBlock)readyBlock {
-	if (self.isExternalViewController) {
-		if (readyBlock) {
-			readyBlock();
-		}
-		return;
-	}
-	
-	__block RNNReactViewReadyCompletionBlock readyBlockCopy = readyBlock;
-	UIView* reactView = [self.creator createRootView:self.layoutInfo.name rootViewId:self.layoutInfo.componentId availableSize:[UIScreen mainScreen].bounds.size reactViewReadyBlock:^{
-		[_presenter renderComponents:self.resolveOptions perform:^{
-			if (readyBlockCopy) {
-				readyBlockCopy();
-				readyBlockCopy = nil;
-			}
-		}];
-	}];
-	
-	self.view = reactView;
-	
-	if (!wait && readyBlock) {
-		readyBlockCopy();
-		readyBlockCopy = nil;
-	}
+- (void)loadView {
+	[self renderReactViewIfNeeded];
+}
+
+- (void)render {
+    if (!self.waitForRender)
+        [self readyForPresentation];
+    else
+        [self renderReactViewIfNeeded];
+}
+
+- (void)renderReactViewIfNeeded {
+    if (!self.isViewLoaded) {
+        self.view = [self.creator createRootView:self.layoutInfo.name rootViewId:self.layoutInfo.componentId reactViewReadyBlock:^{
+            [self->_presenter renderComponents:self.resolveOptions perform:^{
+                [self readyForPresentation];
+            }];
+        }];
+    } else {
+        [self readyForPresentation];
+    }
 }
 
 - (UIViewController *)getCurrentChild {
 	return self.resolveOptions.customTransition.animations != nil;
 }
 
-- (BOOL)isExternalViewController {
-	return !self.creator;
-}
-
 - (BOOL)prefersStatusBarHidden {
 	return [_presenter isStatusBarVisibility:self.navigationController resolvedOptions:self.resolveOptions];
 }

lib/ios/RNNComponentViewCreator.h

 
 @protocol RNNComponentViewCreator
 
-- (RNNReactView*)createRootView:(NSString*)name rootViewId:(NSString*)rootViewId availableSize:(CGSize)availableSize reactViewReadyBlock:(RNNReactViewReadyCompletionBlock)reactViewReadyBlock;
+- (RNNReactView*)createRootView:(NSString*)name rootViewId:(NSString*)rootViewId reactViewReadyBlock:(RNNReactViewReadyCompletionBlock)reactViewReadyBlock;
 
 - (UIView*)createRootViewFromComponentOptions:(RNNComponentOptions*)componentOptions;
 

lib/ios/RNNControllerFactory.h

 #import "RNNEventEmitter.h"
 #import "RNNReactComponentRegistry.h"
 #import "RNNNavigationOptions.h"
+#import "BottomTabsAttachModeFactory.h"
 
 @interface RNNControllerFactory : NSObject
 
 -(instancetype)initWithRootViewCreator:(id <RNNComponentViewCreator>)creator
-						  eventEmitter:(RNNEventEmitter*)eventEmitter
-								 store:(RNNExternalComponentStore *)store
-					  componentRegistry:(RNNReactComponentRegistry *)componentRegistry
-							 andBridge:(RCTBridge*)bridge;
+                          eventEmitter:(RNNEventEmitter*)eventEmitter
+                                 store:(RNNExternalComponentStore *)store
+                     componentRegistry:(RNNReactComponentRegistry *)componentRegistry
+                             andBridge:(RCTBridge*)bridge
+           bottomTabsAttachModeFactory:(BottomTabsAttachModeFactory *)bottomTabsAttachModeFactory;
 
 - (UIViewController *)createLayout:(NSDictionary*)layout;
 

lib/ios/RNNControllerFactory.m

 #import "RNNBottomTabsController.h"
 #import "RNNTopTabsViewController.h"
 #import "RNNComponentViewController.h"
+#import "RNNExternalViewController.h"
+#import "BottomTabsBaseAttacher.h"
+#import "BottomTabsAttachModeFactory.h"
 
 @implementation RNNControllerFactory {
 	id<RNNComponentViewCreator> _creator;
 	RNNExternalComponentStore *_store;
 	RCTBridge *_bridge;
 	RNNReactComponentRegistry* _componentRegistry;
+    BottomTabsAttachModeFactory* _bottomTabsAttachModeFactory;
 }
 
 # pragma mark public
 
 
 - (instancetype)initWithRootViewCreator:(id <RNNComponentViewCreator>)creator
-						   eventEmitter:(RNNEventEmitter*)eventEmitter
-								  store:(RNNExternalComponentStore *)store
-					   componentRegistry:(RNNReactComponentRegistry *)componentRegistry
-							  andBridge:(RCTBridge *)bridge {
+                           eventEmitter:(RNNEventEmitter*)eventEmitter
+                                  store:(RNNExternalComponentStore *)store
+                      componentRegistry:(RNNReactComponentRegistry *)componentRegistry
+                              andBridge:(RCTBridge *)bridge
+            bottomTabsAttachModeFactory:(BottomTabsAttachModeFactory *)bottomTabsAttachModeFactory {
 	
 	self = [super init];
 	
 	_bridge = bridge;
 	_store = store;
 	_componentRegistry = componentRegistry;
+    _bottomTabsAttachModeFactory = bottomTabsAttachModeFactory;
 
 	return self;
 }
 
+- (void)setDefaultOptions:(RNNNavigationOptions *)defaultOptions {
+    _defaultOptions = defaultOptions;
+    _bottomTabsAttachModeFactory.defaultOptions = defaultOptions;
+}
+
 - (UIViewController *)createLayout:(NSDictionary*)layout {
 	UIViewController* layoutViewController = [self fromTree:layout];
 	return layoutViewController;
 	
 	UIViewController* externalVC = [_store getExternalComponent:layoutInfo bridge:_bridge];
 	
-	RNNComponentViewController* component = [[RNNComponentViewController alloc] initExternalComponentWithLayoutInfo:layoutInfo eventEmitter:_eventEmitter presenter:presenter options:options defaultOptions:_defaultOptions];
-	[component bindViewController:externalVC];
+    RNNExternalViewController* component = [[RNNExternalViewController alloc] initWithLayoutInfo:layoutInfo eventEmitter:_eventEmitter presenter:presenter options:options defaultOptions:_defaultOptions viewController:externalVC];
 	
 	return component;
 }
 	return stack;
 }
 
--(UIViewController *)createBottomTabs:(RNNLayoutNode*)node {
-	RNNLayoutInfo* layoutInfo = [[RNNLayoutInfo alloc] initWithNode:node];
-	RNNNavigationOptions* options = [[RNNNavigationOptions alloc] initWithDict:node.data[@"options"]];
-	RNNBottomTabsPresenter* presenter = [[RNNBottomTabsPresenter alloc] initWithDefaultOptions:_defaultOptions];
-	NSArray *childViewControllers = [self extractChildrenViewControllersFromNode:node];
-	return [[RNNBottomTabsController alloc] initWithLayoutInfo:layoutInfo
-																					  creator:_creator
-																					  options:options
-																			   defaultOptions:_defaultOptions
-																					presenter:presenter
-																				 eventEmitter:_eventEmitter
-																		 childViewControllers:childViewControllers
-	];
+- (UIViewController *)createBottomTabs:(RNNLayoutNode*)node {
+    RNNLayoutInfo* layoutInfo = [[RNNLayoutInfo alloc] initWithNode:node];
+    RNNNavigationOptions* options = [[RNNNavigationOptions alloc] initWithDict:node.data[@"options"]];
+    RNNBottomTabsPresenter* presenter = [[RNNBottomTabsPresenter alloc] initWithDefaultOptions:_defaultOptions];
+	BottomTabsBaseAttacher* bottomTabsAttacher = [_bottomTabsAttachModeFactory fromOptions:options];
+    
+    NSArray *childViewControllers = [self extractChildrenViewControllersFromNode:node];
+    return [[RNNBottomTabsController alloc] initWithLayoutInfo:layoutInfo
+                                                       creator:_creator
+                                                       options:options
+                                                defaultOptions:_defaultOptions
+                                                     presenter:presenter
+                                                  eventEmitter:_eventEmitter
+                                          childViewControllers:childViewControllers
+                                            bottomTabsAttacher:bottomTabsAttacher
+            ];
 }
 
 - (UIViewController *)createTopTabs:(RNNLayoutNode*)node {

lib/ios/RNNExternalViewController.h

+#import "RNNComponentViewController.h"
+
+@interface RNNExternalViewController : RNNComponentViewController
+
+- (instancetype)initWithLayoutInfo:(RNNLayoutInfo *)layoutInfo eventEmitter:(RNNEventEmitter *)eventEmitter presenter:(RNNComponentPresenter *)presenter options:(RNNNavigationOptions *)options defaultOptions:(RNNNavigationOptions *)defaultOptions viewController:(UIViewController *)viewController;
+
+@end

lib/ios/RNNExternalViewController.m

+#import "RNNExternalViewController.h"
+
+@implementation RNNExternalViewController
+
+- (instancetype)initWithLayoutInfo:(RNNLayoutInfo *)layoutInfo eventEmitter:(RNNEventEmitter *)eventEmitter presenter:(RNNComponentPresenter *)presenter options:(RNNNavigationOptions *)options defaultOptions:(RNNNavigationOptions *)defaultOptions viewController:(UIViewController *)viewController {
+	self = [super initWithLayoutInfo:layoutInfo rootViewCreator:nil eventEmitter:eventEmitter presenter:presenter options:options defaultOptions:defaultOptions];
+    [self bindViewController:viewController];
+	return self;
+}
+
+- (void)bindViewController:(UIViewController *)viewController {
+    [self addChildViewController:viewController];
+    [self.view addSubview:viewController.view];
+    [viewController didMoveToParentViewController:self];
+}
+
+- (void)loadView {
+	self.view = [UIView new];
+}
+
+- (void)render {
+	[self readyForPresentation];
+}
+
+@end

lib/ios/RNNLayoutProtocol.h

 					  eventEmitter:(RNNEventEmitter *)eventEmitter
 			  childViewControllers:(NSArray *)childViewControllers;
 
-- (void)renderTreeAndWait:(BOOL)wait perform:(RNNReactViewReadyCompletionBlock)readyBlock;
+- (void)render;
 
 - (UIViewController<RNNLayoutProtocol> *)getCurrentChild;
 
 
 - (void)onChildWillAppear;
 
+- (void)readyForPresentation;
+
 @end

lib/ios/RNNReactRootViewCreator.m

 	return self;
 }
 
-- (RNNReactView*)createRootView:(NSString*)name rootViewId:(NSString*)rootViewId availableSize:(CGSize)availableSize reactViewReadyBlock:(RNNReactViewReadyCompletionBlock)reactViewReadyBlock {
+- (RNNReactView*)createRootView:(NSString*)name rootViewId:(NSString*)rootViewId reactViewReadyBlock:(RNNReactViewReadyCompletionBlock)reactViewReadyBlock {
 	if (!rootViewId) {
 		@throw [NSException exceptionWithName:@"MissingViewId" reason:@"Missing view id" userInfo:nil];
 	}
 	RNNReactView *view = [[RNNReactView alloc] initWithBridge:_bridge
 												   moduleName:name
 											initialProperties:@{@"componentId": rootViewId}
-												availableSize:availableSize
 										  reactViewReadyBlock:reactViewReadyBlock];
 	return view;
 }
 
 - (UIView*)createRootViewFromComponentOptions:(RNNComponentOptions*)componentOptions {
-	return [self createRootView:componentOptions.name.get rootViewId:componentOptions.componentId.get availableSize:CGSizeZero reactViewReadyBlock:nil];
+	return [self createRootView:componentOptions.name.get rootViewId:componentOptions.componentId.get reactViewReadyBlock:nil];
 }
 
 - (UIView*)createRootViewFromComponentOptions:(RNNComponentOptions*)componentOptions reactViewReadyBlock:(RNNReactViewReadyCompletionBlock)reactViewReadyBlock {
-	return [self createRootView:componentOptions.name.get rootViewId:componentOptions.componentId.get availableSize:CGSizeZero reactViewReadyBlock:reactViewReadyBlock];
+	return [self createRootView:componentOptions.name.get rootViewId:componentOptions.componentId.get reactViewReadyBlock:reactViewReadyBlock];
 }
 
 @end

lib/ios/RNNReactView.h

 
 @interface RNNReactView : RCTRootView <RCTRootViewDelegate>
 
-- (instancetype)initWithBridge:(RCTBridge *)bridge moduleName:(NSString *)moduleName initialProperties:(NSDictionary *)initialProperties availableSize:(CGSize)availableSize reactViewReadyBlock:(RNNReactViewReadyCompletionBlock)reactViewReadyBlock;
+- (instancetype)initWithBridge:(RCTBridge *)bridge moduleName:(NSString *)moduleName initialProperties:(NSDictionary *)initialProperties reactViewReadyBlock:(RNNReactViewReadyCompletionBlock)reactViewReadyBlock;
 
 @property (nonatomic, copy) void (^rootViewDidChangeIntrinsicSize)(CGSize intrinsicSize);
 @property (nonatomic, copy) RNNReactViewReadyCompletionBlock reactViewReadyBlock;

lib/ios/RNNReactView.m

 	BOOL _fillParent;
 }
 
-- (instancetype)initWithBridge:(RCTBridge *)bridge moduleName:(NSString *)moduleName initialProperties:(NSDictionary *)initialProperties availableSize:(CGSize)availableSize reactViewReadyBlock:(RNNReactViewReadyCompletionBlock)reactViewReadyBlock {
+- (instancetype)initWithBridge:(RCTBridge *)bridge moduleName:(NSString *)moduleName initialProperties:(NSDictionary *)initialProperties reactViewReadyBlock:(RNNReactViewReadyCompletionBlock)reactViewReadyBlock {
 	self = [super initWithBridge:bridge moduleName:moduleName initialProperties:initialProperties];
 	[[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(contentDidAppear:) name:RCTContentDidAppearNotification object:nil];
 	 _reactViewReadyBlock = reactViewReadyBlock;
-	[bridge.uiManager setAvailableSize:availableSize forRootView:self];
 	
 	return self;
 }

lib/ios/RNNSideMenuChildVC.m

 	return self;
 }
 
-- (void)renderTreeAndWait:(BOOL)wait perform:(RNNReactViewReadyCompletionBlock)readyBlock {
-	[self.getCurrentChild renderTreeAndWait:wait perform:readyBlock];
+- (void)render {
+	[self.getCurrentChild render];
 }
 
 - (void)setChild:(UIViewController<RNNLayoutProtocol> *)child {

lib/ios/ReactNativeNavigation.xcodeproj/project.pbxproj

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 				50AB0B1B2255F8640039DAED /* UIViewController+LayoutProtocol.m */,
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 			);
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 			sourceTree = "<group>";
 		};
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+				5017D9DF239D2C6C00B74047 /* BottomTabsAttachModeFactory.h */,
+				5017D9E0239D2C6C00B74047 /* BottomTabsAttachModeFactory.m */,
+			);
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+			sourceTree = "<group>";
+		};
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+			isa = PBXGroup;
+			children = (
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+				5017D9E9239D2F9D00B74047 /* BottomTabsTogetherAttacher.m */,
+				5017D9EC239D2FAF00B74047 /* BottomTabsAfterInitialTabAttacher.h */,
+				5017D9ED239D2FAF00B74047 /* BottomTabsAfterInitialTabAttacher.m */,
+				5017D9F0239D2FCB00B74047 /* BottomTabsOnSwitchToTabAttacher.h */,
+				5017D9F1239D2FCB00B74047 /* BottomTabsOnSwitchToTabAttacher.m */,
+			);
+			name = Attachers;
+			sourceTree = "<group>";
+		};
 		5038A3C3216E2D74009280BC /* Params */ = {
 			isa = PBXGroup;
 			children = (
 				503955962174864E00B0A663 /* NullDouble.m */,
 				309877ADF638DF25FF0DA8A1 /* NoColor.m */,
 				309874C5B132A51A03DAA3BF /* NoColor.h */,
+				50344D2623A03DB4004B6A7C /* BottomTabsAttachMode.h */,
+				50344D2723A03DB4004B6A7C /* BottomTabsAttachMode.m */,
 			);
 			name = Params;
 			sourceTree = "<group>";
 			name = HMSegmentControl;
 			sourceTree = "<group>";
 		};
+		50BAFE482399403200798674 /* Child View Controllers */ = {
+			isa = PBXGroup;
+			children = (
+				7BEF0D161E437684003E96B0 /* RNNComponentViewController.h */,
+				7BEF0D171E437684003E96B0 /* RNNComponentViewController.m */,
+				50BAFE492399405800798674 /* RNNExternalViewController.h */,
+				50BAFE4A2399405800798674 /* RNNExternalViewController.m */,
+			);
+			name = "Child View Controllers";
+			sourceTree = "<group>";
+		};
 		50D031312005146C00386B3D /* Managers */ = {
 			isa = PBXGroup;
 			children = (
 				505EDD39214FA7E80071C7DE /* Presenters */,
 				5012242C2173E0A4000F5F98 /* Parent ViewControllers */,
 				5012242D2173E0E0000F5F98 /* Protocols */,
+				50BAFE482399403200798674 /* Child View Controllers */,
 				50570BE82063E09B006A1B5C /* RNNTitleViewHelper.h */,
+				50570BE92063E09B006A1B5C /* RNNTitleViewHelper.m */,
 				501CD31D214A5B6900A6E225 /* RNNLayoutInfo.h */,
 				501CD31E214A5B6900A6E225 /* RNNLayoutInfo.m */,
 				501E0215213E7EA3003365C5 /* RNNReactView.h */,
 				501E0216213E7EA3003365C5 /* RNNReactView.m */,
-				50570BE92063E09B006A1B5C /* RNNTitleViewHelper.m */,
-				26916C941E4B9CCC00D13680 /* RNNComponentViewCreator.h */,
 				26916C961E4B9E7700D13680 /* RNNReactRootViewCreator.h */,
 				26916C971E4B9E7700D13680 /* RNNReactRootViewCreator.m */,
 				7BA500761E254908001B9E1B /* RNNSplashScreen.h */,
 				7BA500771E254908001B9E1B /* RNNSplashScreen.m */,
 				7BEF0D1A1E43771B003E96B0 /* RNNLayoutNode.h */,
 				7BEF0D1B1E43771B003E96B0 /* RNNLayoutNode.m */,
-				7BEF0D161E437684003E96B0 /* RNNComponentViewController.h */,
-				7BEF0D171E437684003E96B0 /* RNNComponentViewController.m */,
-				7BC9346C1E26886E00EFA125 /* RNNControllerFactory.h */,
-				7BC9346D1E26886E00EFA125 /* RNNControllerFactory.m */,
 				21B85E5E1F44482A00B314B5 /* RNNNavigationButtons.h */,
 				21B85E5C1F44480200B314B5 /* RNNNavigationButtons.m */,
 				214545261F4DC164006E8DA1 /* RNNUIBarButtonItem.h */,
 			children = (
 				E5F6C39B22DB4CB90093C2CE /* Utils */,
 				214545271F4DC7ED006E8DA1 /* Helpers */,
+				5017D9DE239D2C1300B74047 /* Factories */,
+				5017D9E3239D2CC300B74047 /* Attachers */,
 				7BA500731E2544B9001B9E1B /* ReactNativeNavigation.h */,
 				7BA500741E2544B9001B9E1B /* ReactNativeNavigation.m */,
 				2DCD9193200014A900EDC75D /* RNNBridgeManager.h */,
 				7B1126A31E2D2B6C00F9B03B /* RNNSplashScreen.h in Headers */,
 				5038A3D2216E364C009280BC /* Text.h in Headers */,
 				261F0E641E6EC94900989DE2 /* RNNModalManager.h in Headers */,
+				50344D2823A03DB4004B6A7C /* BottomTabsAttachMode.h in Headers */,
 				5012242621737278000F5F98 /* NullImage.h in Headers */,
 				5038A3B9216DFCFD009280BC /* UITabBarController+RNNOptions.h in Headers */,
 				50644A2020E11A720026709C /* Constants.h in Headers */,
 				E8367B801F7A8A4700675C05 /* VICMAImageView.h in Headers */,
 				263905E61E4CAC950023D7D3 /* RNNSideMenuChildVC.h in Headers */,
 				50F5DFC51F407AA0001A00BC /* RNNStackController.h in Headers */,
+				50BAFE4B2399405800798674 /* RNNExternalViewController.h in Headers */,
 				5047E4F42267568800908DD3 /* RNNExternalComponentStore.h in Headers */,
 				21B85E5F1F44482A00B314B5 /* RNNNavigationButtons.h in Headers */,
 				7BEF0D181E437684003E96B0 /* RNNComponentViewController.h in Headers */,
 				50E5F7952240EBD6002AFEAD /* RNNAnimationsTransitionDelegate.h in Headers */,
 				7B1126A71E2D2B6C00F9B03B /* RNNEventEmitter.h in Headers */,
 				E8A430111F9CB87B00B61A20 /* RNNAnimatedView.h in Headers */,
+				5017D9E1239D2C6C00B74047 /* BottomTabsAttachModeFactory.h in Headers */,
 				E5F6C3AC22DB4D0F0093C2CE /* UITabBarController+RNNUtils.h in Headers */,
 				506317AA220B547400B26FC3 /* UIImage+insets.h in Headers */,
 				5038A3C6216E2D93009280BC /* Number.h in Headers */,
 				50BE951320B5A787004F5DF5 /* RNNStatusBarOptions.h in Headers */,
 				50570BEA2063E09B006A1B5C /* RNNTitleViewHelper.h in Headers */,
 				50495956216F6B3D006D2B81 /* DictionaryParser.h in Headers */,
+				5017D9E6239D2D9E00B74047 /* BottomTabsBaseAttacher.h in Headers */,
 				4534E72520CB6724009F8185 /* RNNLargeTitleOptions.h in Headers */,
 				390AD477200F499D00A8250D /* RNNSwizzles.h in Headers */,
 				263905B11E4C6F440023D7D3 /* MMDrawerController.h in Headers */,
 				50495952216F62BD006D2B81 /* NullNumber.h in Headers */,
 				5012242221736883000F5F98 /* NullColor.h in Headers */,
 				50570B262061473D006A1B5C /* RNNTitleOptions.h in Headers */,
+				5017D9EE239D2FAF00B74047 /* BottomTabsAfterInitialTabAttacher.h in Headers */,
 				50395593217485B000B0A663 /* Double.h in Headers */,
 				5050465421F8F4490035497A /* RNNReactComponentRegistry.h in Headers */,
 				504AFE741FFFF0540076E904 /* RNNTopTabsOptions.h in Headers */,
 				505EDD4A214FDA800071C7DE /* RCTConvert+Modal.h in Headers */,
 				5049595A216F6B46006D2B81 /* NullDictionary.h in Headers */,
 				501224062173592D000F5F98 /* RNNBottomTabsPresenter.h in Headers */,
+				5017D9F2239D2FCB00B74047 /* BottomTabsOnSwitchToTabAttacher.h in Headers */,
 				50706E6D20CE7CA5003345C3 /* UIImage+tint.h in Headers */,
 				50A246372395399700A192C5 /* RNNModalOptions.h in Headers */,
 				309874B40D202C9718F15CBD /* UIView+Utils.h in Headers */,
 				3098730BC3B4DE41104D9CC4 /* RNNDotIndicatorPresenter.h in Headers */,
 				309877F473AECC05FB3B9362 /* UITabBarController+RNNUtils.h in Headers */,
 				3098702E6833E5CC16D91CE3 /* NoColor.h in Headers */,
+				5017D9EA239D2F9D00B74047 /* BottomTabsTogetherAttacher.h in Headers */,
 			);
 			runOnlyForDeploymentPostprocessing = 0;
 		};
 				507F43CA1FF4F9CC00D9425B /* RNNTopTabOptions.m in Sources */,
 				26916C991E4B9E7700D13680 /* RNNReactRootViewCreator.m in Sources */,
 				5064495E20DC62B90026709C /* RNNSideMenuSideOptions.m in Sources */,
+				5017D9EB239D2F9D00B74047 /* BottomTabsTogetherAttacher.m in Sources */,
 				E5F6C3AD22DB4D0F0093C2CE /* UITabBarController+RNNUtils.m in Sources */,
 				214545251F4DC125006E8DA1 /* RNNUIBarButtonItem.m in Sources */,
 				263905B81E4C6F440023D7D3 /* UIViewController+MMDrawerController.m in Sources */,
 				505EDD3D214FA8000071C7DE /* RNNComponentPresenter.m in Sources */,
 				E33AC20820B5C4F90090DB8A /* RNNSplitViewOptions.m in Sources */,
 				E33AC20020B5BA0B0090DB8A /* RNNSplitViewController.m in Sources */,
+				50BAFE4C2399405800798674 /* RNNExternalViewController.m in Sources */,
 				5038A3C2216E1E66009280BC /* RNNFontAttributesCreator.m in Sources */,
 				506317AB220B547400B26FC3 /* UIImage+insets.m in Sources */,
 				E8A430121F9CB87B00B61A20 /* RNNAnimatedView.m in Sources */,
 				507F43F51FF4FCFE00D9425B /* HMSegmentedControl.m in Sources */,
+				5017D9E7239D2D9E00B74047 /* BottomTabsBaseAttacher.m in Sources */,
 				5012242321736883000F5F98 /* NullColor.m in Sources */,
 				50451D0A2042E20600695F00 /* RNNAnimationsOptions.m in Sources */,
 				5039558C2174829400B0A663 /* IntNumberParser.m in Sources */,
 				507F43C61FF4F17C00D9425B /* RNNTopTabsViewController.m in Sources */,
 				50706E6E20CE7CA5003345C3 /* UIImage+tint.m in Sources */,
+				50344D2923A03DB4004B6A7C /* BottomTabsAttachMode.m in Sources */,
 				501224072173592D000F5F98 /* RNNBottomTabsPresenter.m in Sources */,
 				50A00C38200F84D6000F01A6 /* RNNOverlayOptions.m in Sources */,
 				5039559C2174867000B0A663 /* DoubleParser.m in Sources */,
+				5017D9EF239D2FAF00B74047 /* BottomTabsAfterInitialTabAttacher.m in Sources */,
 				5008641223856A2D00A55BE9 /* UITabBar+utils.m in Sources */,
 				E5F6C3A822DB4D0F0093C2CE /* UIView+Utils.m in Sources */,
 				5049593F216F5D73006D2B81 /* BoolParser.m in Sources */,
 				E8E5182F1F83A48B000467AC /* RNNTransitionStateHolder.m in Sources */,
 				263905B61E4C6F440023D7D3 /* MMExampleDrawerVisualStateManager.m in Sources */,
 				5038A3D3216E364C009280BC /* Text.m in Sources */,
+				5017D9E2239D2C6C00B74047 /* BottomTabsAttachModeFactory.m in Sources */,
 				5012240F21735999000F5F98 /* RNNBasePresenter.m in Sources */,
 				5038A375216CDDB6009280BC /* UIViewController+SideMenuController.m in Sources */,
 				E8E518331F83B3E0000467AC /* RNNUtils.m in Sources */,
 				30987AB5137F264FA06DA289 /* DotIndicatorOptions.m in Sources */,
 				30987D71FB4FEEAC8D8978E8 /* DotIndicatorParser.m in Sources */,
 				30987B23F288EB3A78B7F27C /* RNNDotIndicatorPresenter.m in Sources */,
+				5017D9F3239D2FCB00B74047 /* BottomTabsOnSwitchToTabAttacher.m in Sources */,
 				309878CC9D33CE1CF991EBD1 /* NoColor.m in Sources */,
 			);
 			runOnlyForDeploymentPostprocessing = 0;

lib/ios/UIViewController+LayoutProtocol.h

 
 @interface UIViewController (LayoutProtocol) <RNNLayoutProtocol>
 
-- (void)renderTreeAndWait:(BOOL)wait perform:(RNNReactViewReadyCompletionBlock)readyBlock;
+- (void)render;
 
 - (UIViewController *)getCurrentChild;
 
+- (UIViewController *)presentedComponentViewController;
+
 - (void)mergeOptions:(RNNNavigationOptions *)options;
 
 - (void)mergeChildOptions:(RNNNavigationOptions *)options;
 
 - (RNNNavigationOptions *)resolveOptions;
 
+- (RNNNavigationOptions *)resolveOptionsWithDefault;
+
 - (void)setDefaultOptions:(RNNNavigationOptions *)defaultOptions;
 
 - (void)overrideOptions:(RNNNavigationOptions *)options;
 
+- (void)readyForPresentation;
+
 @property (nonatomic, retain) RNNBasePresenter* presenter;
 @property (nonatomic, retain) RNNLayoutInfo* layoutInfo;
 @property (nonatomic, strong) RNNNavigationOptions* options;
 @property (nonatomic, strong) RNNNavigationOptions* defaultOptions;
 @property (nonatomic, strong) RNNEventEmitter* eventEmitter;
 @property (nonatomic) id<RNNComponentViewCreator> creator;
+@property (nonatomic) RNNReactViewReadyCompletionBlock reactViewReadyCallback;
+@property (nonatomic) BOOL waitForRender;
 
 @end

lib/ios/UIViewController+LayoutProtocol.m

     return (RNNNavigationOptions *) [self.options mergeInOptions:self.getCurrentChild.resolveOptions.copy];
 }
 
+- (RNNNavigationOptions *)resolveOptionsWithDefault {
+    return [(RNNNavigationOptions *) [self.options mergeInOptions:self.getCurrentChild.resolveOptions.copy] withDefault:self.defaultOptions];
+}
+
 - (void)overrideOptions:(RNNNavigationOptions *)options {
 	[self.options overrideOptions:options];
 }
 	return interfaceOrientationMask;
 }
 
-- (void)renderTreeAndWait:(BOOL)wait perform:(RNNReactViewReadyCompletionBlock)readyBlock {
-	dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_HIGH, 0), ^{
-		dispatch_group_t group = dispatch_group_create();
-		for (UIViewController* childViewController in self.childViewControllers) {
-			dispatch_group_enter(group);
-			dispatch_async(dispatch_get_main_queue(), ^{
-				[childViewController renderTreeAndWait:wait perform:^{
-					dispatch_group_leave(group);
-				}];
-			});
-		}
-		
-		dispatch_group_enter(group);
-		[self.presenter renderComponents:self.resolveOptions perform:^{
-			dispatch_group_leave(group);
-		}];
-		dispatch_group_wait(group, DISPATCH_TIME_FOREVER);
-		
-		dispatch_async(dispatch_get_main_queue(), ^{
-			readyBlock();
-		});
-	});
+- (void)render {
+    if (!self.waitForRender) {
+        [self readyForPresentation];
+    }
+    
+    [self.presentedComponentViewController setReactViewReadyCallback:^{
+        [self.presenter renderComponents:self.resolveOptionsWithDefault perform:^{
+            [self readyForPresentation];
+        }];
+    }];
+    
+    [self.presentedComponentViewController render];
+}
+
+- (void)readyForPresentation {
+    if (self.reactViewReadyCallback) {
+        self.reactViewReadyCallback();
+        self.reactViewReadyCallback = nil;
+    }
+    
+    [self.parentViewController readyForPresentation];
 }
 
 - (UIViewController *)getCurrentChild {
-	return nil;
+    return nil;
+}
+
+- (UIViewController *)presentedComponentViewController {
+    return self.getCurrentChild ? self.getCurrentChild.presentedComponentViewController : self;
 }
 
 - (CGFloat)getTopBarHeight {
 	objc_setAssociatedObject(self, @selector(creator), creator, OBJC_ASSOCIATION_RETAIN_NONATOMIC);
 }
 
+- (RNNReactViewReadyCompletionBlock)reactViewReadyCallback {
+    return objc_getAssociatedObject(self, @selector(reactViewReadyCallback));
+}
+
+- (void)setReactViewReadyCallback:(RNNReactViewReadyCompletionBlock)reactViewReadyCallback {
+    objc_setAssociatedObject(self, @selector(reactViewReadyCallback), reactViewReadyCallback, OBJC_ASSOCIATION_RETAIN_NONATOMIC);
+}
+
+- (BOOL)waitForRender {
+    return [objc_getAssociatedObject(self.parentViewController ?: self, @selector(waitForRender)) boolValue];
+}
 
+- (void)setWaitForRender:(BOOL)waitForRender {
+    objc_setAssociatedObject(self, @selector(waitForRender), [NSNumber numberWithBool:waitForRender], OBJC_ASSOCIATION_RETAIN_NONATOMIC);
+}
 
 @end

lib/ios/Utils/UITabBarController+RNNUtils.h

 #import <UIKit/UIKit.h>
 
 @interface UITabBarController (RNNUtils)
+
 - (UIView *)getTabView:(int)tabIndex;
 
 - (UIView *)getTabIcon:(int)tabIndex;
-@end
+
+- (NSArray *)deselectedViewControllers;
+
+@end

lib/ios/Utils/UITabBarController+RNNUtils.m

     UIView *tab = [self getTabView:tabIndex];
     return [tab findChildByClass:[UIImageView class]];
 }
-@end
+
+- (NSArray *)deselectedViewControllers {
+    NSMutableArray* childViewControllers = [NSMutableArray arrayWithArray:self.childViewControllers];
+    [childViewControllers removeObject:self.selectedViewController];
+    return [NSArray arrayWithArray:childViewControllers];
+}
+
+@end

playground/ios/NavigationTests/RNNCommandsHandlerTest.m

 #import <ReactNativeNavigation/RNNErrorHandler.h>
 #import <OCMock/OCMock.h>
 #import "RNNLayoutManager.h"
+#import "RNNBottomTabsController.h"
+#import "BottomTabsAttachModeFactory.h"
 
 @interface MockUIApplication : NSObject
 
 	self.eventEmmiter = [OCMockObject partialMockForObject:[RNNEventEmitter new]];
 	self.overlayManager = [OCMockObject partialMockForObject:[RNNOverlayManager new]];
 	self.modalManager = [OCMockObject partialMockForObject:[RNNModalManager new]];
-	self.controllerFactory = [OCMockObject partialMockForObject:[[RNNControllerFactory alloc] initWithRootViewCreator:nil eventEmitter:self.eventEmmiter store:nil componentRegistry:nil andBridge:nil]];
+	self.controllerFactory = [OCMockObject partialMockForObject:[[RNNControllerFactory alloc] initWithRootViewCreator:nil eventEmitter:self.eventEmmiter store:nil componentRegistry:nil andBridge:nil bottomTabsAttachModeFactory:[BottomTabsAttachModeFactory new]]];
 	self.uut = [[RNNCommandsHandler alloc] initWithControllerFactory:self.controllerFactory eventEmitter:self.eventEmmiter stackManager:[RNNNavigationStackManager new] modalManager:self.modalManager overlayManager:self.overlayManager mainWindow:_mainWindow];
-	self.vc1 = [RNNComponentViewController new];
-	self.vc2 = [RNNComponentViewController new];
-	self.vc3 = [RNNComponentViewController new];
+	self.vc1 = self.generateComponent;
+	self.vc2 = self.generateComponent;
+	self.vc3 = self.generateComponent;
 	_nvc = [[MockUINavigationController alloc] init];
 	[_nvc setViewControllers:@[self.vc1, self.vc2, self.vc3]];
 	OCMStub([self.sharedApplication keyWindow]).andReturn(self.mainWindow);
 }
 
+- (RNNComponentViewController *)generateComponent {
+	return [[RNNComponentViewController alloc] initWithLayoutInfo:nil rootViewCreator:[[RNNTestRootViewCreator alloc] init] eventEmitter:nil presenter:[RNNComponentPresenter new] options:[[RNNNavigationOptions alloc] initWithDict:@{}] defaultOptions:nil];
+}
 
 - (void)testAssertReadyForEachMethodThrowsExceptoins {
 	NSArray* methods = [self getPublicMethodNamesForObject:self.uut];
 
 - (void)testShowOverlay_withCreatedLayout {
 	[self.uut setReadyToReceiveCommands:true];
-	UIViewController* layoutVC = [RNNComponentViewController new];
+	UIViewController* layoutVC = self.generateComponent;
 	OCMStub([self.controllerFactory createLayout:[OCMArg any]]).andReturn(layoutVC);
 	
 	[[self.overlayManager expect] showOverlayWindow:[OCMArg any]];
 	[self.uut setReadyToReceiveCommands:true];
 	id classMock = OCMClassMock([RNNLayoutManager class]);
 	OCMStub(ClassMethod([classMock findComponentForId:@"vc1"])).andReturn(_nvc);
+	self.vc2.options.animations.setStackRoot.enable = [[Bool alloc] initWithBOOL:NO];
 	
 	[self.uut setStackRoot:@"vc1" commandId:@"" children:nil completion:^{
-		
+
 	} rejection:^(NSString *code, NSString *message, NSError *error) {
 		
 	}];
 	OCMStub(ClassMethod([classMock findComponentForId:@"vc1"])).andReturn(_nvc);
 	OCMStub([self.controllerFactory createChildrenLayout:[OCMArg any]]).andReturn(newViewControllers);
 	[self.uut setReadyToReceiveCommands:true];
+	
+	_vc3.options.animations.setStackRoot.enable = [[Bool alloc] initWithBOOL:NO];
 	[self.uut setStackRoot:@"vc1" commandId:@"" children:nil completion:^{
-		
+	
 	} rejection:^(NSString *code, NSString *message, NSError *error) {
 		
 	}];
 		
 	}];
 	
-	[[vc1Mock expect] renderTreeAndWait:NO perform:[OCMArg any]];
-	[[vc2Mock expect] renderTreeAndWait:NO perform:[OCMArg any]];
+	[[vc1Mock expect] render];
+	[[vc2Mock expect] render];
 }
 
 - (void)testSetStackRoot_waitForRender {
 		
 	}];
 	
-	[[vc1Mock expect] renderTreeAndWait:NO perform:[OCMArg any]];
-	[[vc2Mock expect] renderTreeAndWait:YES perform:[OCMArg any]];
+	[[vc1Mock expect] render];
+	[[vc2Mock expect] render];
 }
 
 - (void)testSetRoot_waitForRenderTrue {
 	id mockedVC = [OCMockObject partialMockForObject:self.vc1];
 	OCMStub([self.controllerFactory createLayout:[OCMArg any]]).andReturn(mockedVC);
 	
-	[[mockedVC expect] renderTreeAndWait:YES perform:[OCMArg any]];
+	[[mockedVC expect] render];
 	[self.uut setRoot:@{} commandId:@"" completion:^{}];
 	[mockedVC verify];
 }
 	id mockedVC = [OCMockObject partialMockForObject:self.vc1];
 	OCMStub([self.controllerFactory createLayout:[OCMArg any]]).andReturn(mockedVC);
 	
-	[[mockedVC expect] renderTreeAndWait:NO perform:[OCMArg any]];
+	[[mockedVC expect] render];
 	[self.uut setRoot:@{} commandId:@"" completion:^{}];
 	[mockedVC verify];
 }
 
+- (void)testSetRoot_withBottomTabsAttachModeTogether {
+	[self.uut setReadyToReceiveCommands:true];
+	RNNNavigationOptions* options = [[RNNNavigationOptions alloc] initEmptyOptions];
+	options.bottomTabs.tabsAttachMode = [[BottomTabsAttachMode alloc] initWithValue:@"together"];
+	options.animations.setRoot.waitForRender = [[Bool alloc] initWithBOOL:YES];
+
+	BottomTabsBaseAttacher* attacher = [[[BottomTabsAttachModeFactory alloc] initWithDefaultOptions:nil] fromOptions:options];
+	RNNBottomTabsController* tabBarController = [[RNNBottomTabsController alloc] initWithLayoutInfo:nil creator:nil options:options defaultOptions:[[RNNNavigationOptions alloc] initEmptyOptions] presenter:[RNNBasePresenter new] eventEmitter:_eventEmmiter childViewControllers:@[_vc1, _vc2] bottomTabsAttacher:attacher];
+
+	OCMStub([self.controllerFactory createLayout:[OCMArg any]]).andReturn(tabBarController);
+	
+	[self.uut setRoot:@{} commandId:@"" completion:^{}];
+	XCTAssertTrue(_vc1.isViewLoaded);
+	XCTAssertTrue(_vc2.isViewLoaded);
+}
+
+- (void)testSetRoot_withBottomTabsAttachModeOnSwitchToTab {
+	[self.uut setReadyToReceiveCommands:true];
+	RNNNavigationOptions* options = [[RNNNavigationOptions alloc] initEmptyOptions];
+	options.bottomTabs.tabsAttachMode = [[BottomTabsAttachMode alloc] initWithValue:@"onSwitchToTab"];
+	options.animations.setRoot.waitForRender = [[Bool alloc] initWithBOOL:YES];
+	
+	BottomTabsBaseAttacher* attacher = [[[BottomTabsAttachModeFactory alloc] initWithDefaultOptions:nil] fromOptions:options];
+	RNNBottomTabsController* tabBarController = [[RNNBottomTabsController alloc] initWithLayoutInfo:nil creator:nil options:options defaultOptions:[[RNNNavigationOptions alloc] initEmptyOptions] presenter:[RNNBasePresenter new] eventEmitter:_eventEmmiter childViewControllers:@[_vc1, _vc2] bottomTabsAttacher:attacher];
+
+	OCMStub([self.controllerFactory createLayout:[OCMArg any]]).andReturn(tabBarController);
+	
+	[self.uut setRoot:@{} commandId:@"" completion:^{}];
+	XCTAssertTrue(_vc1.isViewLoaded);
+	XCTAssertFalse(_vc2.isViewLoaded);
+	[tabBarController setSelectedIndex:1];
+	XCTAssertTrue(_vc2.isViewLoaded);
+}
+
+- (void)testSetRoot_withBottomTabsAttachModeAfterInitialTab {
+	[self.uut setReadyToReceiveCommands:true];
+	RNNNavigationOptions* options = [[RNNNavigationOptions alloc] initEmptyOptions];
+	options.bottomTabs.tabsAttachMode = [[BottomTabsAttachMode alloc] initWithValue:@"afterInitialTab"];
+	options.animations.setRoot.waitForRender = [[Bool alloc] initWithBOOL:YES];
+
+	BottomTabsBaseAttacher* attacher = [[[BottomTabsAttachModeFactory alloc] initWithDefaultOptions:nil] fromOptions:options];
+	RNNBottomTabsController* tabBarController = [[RNNBottomTabsController alloc] initWithLayoutInfo:nil creator:nil options:options defaultOptions:[[RNNNavigationOptions alloc] initEmptyOptions] presenter:[RNNBasePresenter new] eventEmitter:_eventEmmiter childViewControllers:@[_vc1, _vc2] bottomTabsAttacher:attacher];
+
+	OCMStub([self.controllerFactory createLayout:[OCMArg any]]).andReturn(tabBarController);
+
+	[self.uut setRoot:@{} commandId:@"" completion:^{
+		XCTAssertFalse(self->_vc2.isViewLoaded);
+	}];
+
+	XCTAssertTrue(_vc1.isViewLoaded);
+	XCTAssertTrue(_vc2.isViewLoaded);
+}
+
 - (void)testShowModal_shouldShowAnimated {
 	[self.uut setReadyToReceiveCommands:true];
 	self.vc1.options = [[RNNNavigationOptions alloc] initEmptyOptions];

playground/ios/NavigationTests/RNNControllerFactoryTest.m

 #import "RNNBottomTabsController.h"
 #import "RNNTopTabsViewController.h"
 #import "RNNSplitViewController.h"
+#import "RNNExternalViewController.h"
 
 @interface RNNControllerFactoryTest : XCTestCase
 
 	[super setUp];
 	self.creator = nil;
 	self.store = [RNNExternalComponentStore new];
-	self.factory = [[RNNControllerFactory alloc] initWithRootViewCreator:self.creator eventEmitter:nil store:self.store componentRegistry:nil andBridge:nil];
+	self.factory = [[RNNControllerFactory alloc] initWithRootViewCreator:self.creator eventEmitter:nil store:self.store componentRegistry:nil andBridge:nil bottomTabsAttachModeFactory:[BottomTabsAttachModeFactory new]];
 }
 
 - (void)tearDown {
 							  @"data": @{@"name": @"externalComponent"},
 							  @"children": @[]};
 	id ans = [self.factory createLayout:layout];
-	XCTAssertTrue([ans isMemberOfClass:[RNNComponentViewController class]]);
+	XCTAssertTrue([ans isKindOfClass:[RNNComponentViewController class]]);
+	XCTAssertTrue([ans isMemberOfClass:[RNNExternalViewController class]]);
 }
 
 - (void)testCreateLayout_ComponentStackLayout {

playground/ios/NavigationTests/RNNSideMenuControllerTest.m

 #import <XCTest/XCTest.h>
 #import "RNNSideMenuController.h"
 #import "RNNComponentViewController.h"
+#import "RNNTestRootViewCreator.h"
 
 @interface RNNSideMenuControllerTest : XCTestCase
 @property (nonatomic, strong) RNNSideMenuController *uut;
+@property (nonatomic, strong) RNNTestRootViewCreator *creator;
 @property (nonatomic, strong) RNNSideMenuChildVC *centerVC;
 @property (nonatomic, strong) RNNSideMenuChildVC *leftVC;
 @property (nonatomic, strong) RNNSideMenuChildVC *rightVC;
 
 - (void)setUp {
     [super setUp];
-	_leftVC = [[RNNSideMenuChildVC alloc] initWithLayoutInfo:nil creator:nil options:nil defaultOptions:nil presenter:nil eventEmitter:nil childViewController:[RNNComponentViewController new] type:RNNSideMenuChildTypeLeft];
-	_rightVC = [[RNNSideMenuChildVC alloc] initWithLayoutInfo:nil creator:nil options:nil defaultOptions:nil presenter:nil eventEmitter:nil childViewController:[RNNComponentViewController new] type:RNNSideMenuChildTypeRight];
-	_centerVC =[[RNNSideMenuChildVC alloc] initWithLayoutInfo:nil creator:nil options:nil defaultOptions:nil presenter:nil eventEmitter:nil childViewController:[RNNComponentViewController new] type:RNNSideMenuChildTypeCenter];
+	_creator = [[RNNTestRootViewCreator alloc] init];
+	_leftVC = [[RNNSideMenuChildVC alloc] initWithLayoutInfo:nil creator:nil options:nil defaultOptions:nil presenter:nil eventEmitter:nil childViewController:self.generateComponent type:RNNSideMenuChildTypeLeft];
+	_rightVC = [[RNNSideMenuChildVC alloc] initWithLayoutInfo:nil creator:nil options:nil defaultOptions:nil presenter:nil eventEmitter:nil childViewController:self.generateComponent type:RNNSideMenuChildTypeRight];
+	_centerVC =[[RNNSideMenuChildVC alloc] initWithLayoutInfo:nil creator:nil options:nil defaultOptions:nil presenter:nil eventEmitter:nil childViewController:self.generateComponent type:RNNSideMenuChildTypeCenter];
 	self.uut = [[RNNSideMenuController alloc] initWithLayoutInfo:nil creator:nil childViewControllers:@[_leftVC, _centerVC, _rightVC] options:[[RNNNavigationOptions alloc] initEmptyOptions] defaultOptions:nil presenter:nil eventEmitter:nil];
 }
 
+- (RNNComponentViewController *)generateComponent {
+	return [[RNNComponentViewController alloc] initWithLayoutInfo:nil rootViewCreator:_creator eventEmitter:nil presenter:[RNNComponentPresenter new] options:[[RNNNavigationOptions alloc] initWithDict:@{}] defaultOptions:nil];
+}
+
 - (void)testSetSideMenuWidthShouldUpdateLeftReactViewFrameWidth {
 	[self.uut side:MMDrawerSideLeft width:100];
 	XCTAssertEqual(self.uut.left.child.view.frame.size.width, 100.f);

playground/ios/NavigationTests/RNNTestRootViewCreator.h

 #import <Foundation/Foundation.h>
-#import <ReactNativeNavigation/RNNComponentViewCreator.h>
+#import "RNNComponentViewCreator.h"
 
 @interface RNNTestRootViewCreator : NSObject <RNNComponentViewCreator>
 

playground/ios/Podfile.lock

     - ReactCommon/jscallinvoker (= 0.61.4)
   - ReactNativeKeyboardTrackingView (5.6.1):
     - React
-  - ReactNativeNavigation (4.0.2):
+  - ReactNativeNavigation (4.0.4):
     - React
   - Yoga (1.14.0)
 
   React-RCTVibration: 0f76400ee3cec6edb9c125da49fed279340d145a
   ReactCommon: a6a294e7028ed67b926d29551aa9394fd989c24c
   ReactNativeKeyboardTrackingView: a240a6a0dba852bb107109a7ec7e98b884055977
-  ReactNativeNavigation: f3da2b103f01bc576bbb1a41df67486788dcf6af
+  ReactNativeNavigation: bf2951e30fb873b3ed1e736419c38ed1efe0f6c2
   Yoga: ba3d99dbee6c15ea6bbe3783d1f0cb1ffb79af0f
 
 PODFILE CHECKSUM: 8a6eee15d75935b9144e5228ce8fa2a5b98079e7

playground/ios/playground.xcodeproj/project.pbxproj

 		E58D26602385888C003F36BA /* RNNModalManagerTest.m in Sources */ = {isa = PBXBuildFile; fileRef = E58D26432385888C003F36BA /* RNNModalManagerTest.m */; };
 		E58D26612385888C003F36BA /* RNNTestNoColor.m in Sources */ = {isa = PBXBuildFile; fileRef = E58D26452385888C003F36BA /* RNNTestNoColor.m */; };
 		EFC0DF770EBAEFC23D0CB155 /* Pods_NavigationTests.framework in Frameworks */ = {isa = PBXBuildFile; fileRef = 84E32151E3A71C2B7328BCB4 /* Pods_NavigationTests.framework */; };
+		FE548D2471FE535CFCE8B113 /* Pods_playground.framework in Frameworks */ = {isa = PBXBuildFile; fileRef = 50364D69238E7ECC000E62A2 /* Pods_playground.framework */; };
 /* End PBXBuildFile section */
 
 /* Begin PBXContainerItemProxy section */
 		13B07FB71A68108700A75B9A /* main.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; path = main.m; sourceTree = "<group>"; };
 		4259AF43A23D928FE78B4A3A /* Pods-NavigationTests.debug.xcconfig */ = {isa = PBXFileReference; includeInIndex = 1; lastKnownFileType = text.xcconfig; name = "Pods-NavigationTests.debug.xcconfig"; path = "Target Support Files/Pods-NavigationTests/Pods-NavigationTests.debug.xcconfig"; sourceTree = "<group>"; };
 		4A3340545EAAF11C1F146864 /* Pods_playground.framework */ = {isa = PBXFileReference; explicitFileType = wrapper.framework; includeInIndex = 0; path = Pods_playground.framework; sourceTree = BUILT_PRODUCTS_DIR; };
+		50364D69238E7ECC000E62A2 /* Pods_playground.framework */ = {isa = PBXFileReference; explicitFileType = wrapper.framework; path = Pods_playground.framework; sourceTree = BUILT_PRODUCTS_DIR; };
+		50364D6B238E7F0A000E62A2 /* ReactNativeNavigation.framework */ = {isa = PBXFileReference; explicitFileType = wrapper.framework; path = ReactNativeNavigation.framework; sourceTree = BUILT_PRODUCTS_DIR; };
 		50451D33204451A800695F00 /* RNNCustomViewController.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; name = RNNCustomViewController.h; path = ../../../lib/ios/RNNCustomViewController.h; sourceTree = "<group>"; };
 		50451D34204451A800695F00 /* RNNCustomViewController.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; name = RNNCustomViewController.m; path = ../../../lib/ios/RNNCustomViewController.m; sourceTree = "<group>"; };
 		7F8E255E2E08F6ECE7DF6FE3 /* Pods-playground.release.xcconfig */ = {isa = PBXFileReference; includeInIndex = 1; lastKnownFileType = text.xcconfig; name = "Pods-playground.release.xcconfig"; path = "Target Support Files/Pods-playground/Pods-playground.release.xcconfig"; sourceTree = "<group>"; };
 			files = (
 				E5046080227748EA00212BD8 /* JavaScriptCore.framework in Frameworks */,
 				9D204F3DC4FBCD81583BF99F /* Pods_playground.framework in Frameworks */,
+				FE548D2471FE535CFCE8B113 /* Pods_playground.framework in Frameworks */,
 			);
 			runOnlyForDeploymentPostprocessing = 0;
 		};
 		E504607E227748E900212BD8 /* Frameworks */ = {
 			isa = PBXGroup;
 			children = (
+				50364D6B238E7F0A000E62A2 /* ReactNativeNavigation.framework */,
+				50364D69238E7ECC000E62A2 /* Pods_playground.framework */,
 				E504607F227748EA00212BD8 /* JavaScriptCore.framework */,
 				4A3340545EAAF11C1F146864 /* Pods_playground.framework */,
 				84E32151E3A71C2B7328BCB4 /* Pods_NavigationTests.framework */,

playground/ios/playground.xcodeproj/xcshareddata/xcschemes/playground.xcscheme

       parallelizeBuildables = "NO"
       buildImplicitDependencies = "YES">
       <BuildActionEntries>
+         <BuildActionEntry
+            buildForTesting = "YES"
+            buildForRunning = "YES"
+            buildForProfiling = "YES"
+            buildForArchiving = "YES"
+            buildForAnalyzing = "YES">
+            <BuildableReference
+               BuildableIdentifier = "primary"
+               BlueprintIdentifier = "6ADCF369490C694BEBF31C5B4517D035"
+               BuildableName = "ReactNativeNavigation.framework"
+               BlueprintName = "ReactNativeNavigation"
+               ReferencedContainer = "container:Pods/Pods.xcodeproj">
+            </BuildableReference>
+         </BuildActionEntry>
          <BuildActionEntry
             buildForTesting = "YES"
             buildForRunning = "YES"

playground/src/commons/Options.js

 
 module.exports = {
   setDefaultOptions
-}
+}