Merge branch 'v2' of https://github.com/wix/react-native-navigation into v2

docs/README.md

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lib/ios/RNNBridgeManager.h

 
 - (instancetype)initWithJsCodeLocation:(NSURL *)jsCodeLocation launchOptions:(NSDictionary *)launchOptions;
 
+- (void)registerExternalComponent:(NSString *)name callback:(UIViewController *(^)(void))callback;
+
 @property (readonly, nonatomic, strong) RCTBridge *bridge;
 
 @end

lib/ios/RNNBridgeManager.m

 	return self;
 }
 
+- (void)registerExternalComponent:(NSString *)name callback:(RNNExternalViewCreator)callback {
+	[_store registerExternalComponent:name callback:callback];
+}
+
 # pragma mark - RCTBridgeDelegate
 
 - (NSURL *)sourceURLForBridge:(RCTBridge *)bridge {

lib/ios/RNNControllerFactory.m

 	UIViewController<RNNRootViewProtocol> *result;
 	
 	if (node.isComponent) {
-		result = [self createComponent:node nativeComponent:NO];
+		result = [self createComponent:node];
 	}
 	
 	else if (node.isStack)	{
 	}
 	
 	else if (node.isExternalComponent) {
-		result = [self createComponent:node nativeComponent:YES];
+		result = [self createExternalComponent:node];
 	}
 	
 	if (!result) {
 	return result;
 }
 
-- (UIViewController<RNNRootViewProtocol> *)createComponent:(RNNLayoutNode*)node nativeComponent:(BOOL)nativeComponent {
+- (UIViewController<RNNRootViewProtocol> *)createComponent:(RNNLayoutNode*)node {
 	NSString* name = node.data[@"name"];
 	RNNNavigationOptions* options = [[RNNNavigationOptions alloc] initWithDict:_defaultOptionsDict];
 	[options mergeWith:node.data[@"options"]];
 
 	NSString* componentId = node.nodeId;
-	RNNRootViewController* component = [[RNNRootViewController alloc] initWithName:name withOptions:options withComponentId:componentId rootViewCreator:_creator eventEmitter:_eventEmitter isExternalComponent:nativeComponent];
+	RNNRootViewController* component = [[RNNRootViewController alloc] initWithName:name withOptions:options withComponentId:componentId rootViewCreator:_creator eventEmitter:_eventEmitter isExternalComponent:NO];
 	if (!component.isCustomViewController) {
 		CGSize availableSize = UIApplication.sharedApplication.delegate.window.bounds.size;
 		[_bridge.uiManager setAvailableSize:availableSize forRootView:component.view];
 	return component;
 }
 
+- (UIViewController<RNNRootViewProtocol> *)createExternalComponent:(RNNLayoutNode*)node {
+	NSString* name = node.data[@"name"];
+	
+	UIViewController* externalVC = [_store getExternalComponent:name];
+	RNNNavigationOptions* options = [[RNNNavigationOptions alloc] initWithDict:_defaultOptionsDict];
+	[options mergeWith:node.data[@"options"]];
+	
+	NSString* componentId = node.nodeId;
+	RNNRootViewController* component = [[RNNRootViewController alloc] initWithName:name withOptions:options withComponentId:componentId rootViewCreator:_creator eventEmitter:_eventEmitter isExternalComponent:YES];
+	
+	[component addChildViewController:externalVC];
+	component.view = [[UIView alloc] init];
+	component.view.backgroundColor = [UIColor whiteColor];
+	[component.view addSubview:externalVC.view];
+	
+	return component;
+}
+
+
 - (UIViewController<RNNRootViewProtocol> *)createStack:(RNNLayoutNode*)node {
 	RNNNavigationController* vc = [[RNNNavigationController alloc] init];
 	NSDictionary* options = node.data[@"options"];

lib/ios/RNNRootViewController.m

 	self.creator = creator;
 	self.isExternalComponent = isExternalComponent;
 	
-	if (self.isExternalComponent) {
-		[self addExternalVC:name];
-	} else {
+	if (!self.isExternalComponent) {
 		self.view = [creator createRootView:self.componentName rootViewId:self.componentId];
 	}
 	
 	[self.options.topTab applyOn:self];
 }
 
--(void)addExternalVC:(NSString*)className {
-	if (className != nil) {
-		Class class = NSClassFromString(className);
-		if (class != NULL) {
-			id obj = [[class alloc] init];
-			if (obj != nil && [obj isKindOfClass:[UIViewController class]]) {
-				UIViewController *viewController = (UIViewController*)obj;
-				[self addChildViewController:viewController];
-				self.view = [[UIView alloc] init];
-				self.view.backgroundColor = [UIColor whiteColor];
-				[self.view addSubview:viewController.view];
-			}
-			else {
-				NSLog(@"addExternalVC: could not create instance. Make sure that your class is a UIViewController whihc confirms to RCCExternalViewControllerProtocol");
-			}
-		}
-		else {
-			NSLog(@"addExternalVC: could not create class from string. Check that the proper class name wass passed in ExternalNativeScreenClass");
-		}
-	}
-}
 
 /**
  *	fix for #877, #878

lib/ios/RNNStore.h

 #import "RNNRootViewController.h"
 
 typedef void (^RNNTransitionCompletionBlock)(void);
+typedef UIViewController * (^RNNExternalViewCreator)(void);
 
 @interface RNNStore : NSObject
 
 -(void) removeComponent:(NSString*)componentId;
 -(void) removeComponentByViewControllerInstance:(UIViewController*)componentInstance;
 
+- (void)registerExternalComponent:(NSString *)name callback:(RNNExternalViewCreator)callback;
+- (UIViewController *)getExternalComponent:(NSString *)name;
+
 -(NSString*)componentKeyForInstance:(UIViewController*)instance;
 
 -(void) setReadyToReceiveCommands:(BOOL)isReady;

lib/ios/RNNStore.m

 @implementation RNNStore {
 	NSMapTable* _componentStore;
 	NSMutableArray* _pendingModalIdsToDismiss;
+	NSMutableDictionary* _externalComponentCreators;
 	BOOL _isReadyToReceiveCommands;
 }
 
 	_isReadyToReceiveCommands = false;
 	_componentStore = [NSMapTable strongToWeakObjectsMapTable];
 	_pendingModalIdsToDismiss = [NSMutableArray new];
+	_externalComponentCreators = [NSMutableDictionary new];
 	return self;
 }
 
 	return nil;
 }
 
+- (void)registerExternalComponent:(NSString *)name callback:(RNNExternalViewCreator)callback {
+	[_externalComponentCreators setObject:[callback copy] forKey:name];
+}
+
+- (UIViewController *)getExternalComponent:(NSString *)name {
+	RNNExternalViewCreator creator = [_externalComponentCreators objectForKey:name];
+	return creator();
+}
+
 @end

lib/ios/ReactNativeNavigation.h

 #import <Foundation/Foundation.h>
+#import <UIKit/UIKit.h>
+
+typedef UIViewController * (^RNNExternalViewCreator)(void);
 
 @interface ReactNativeNavigation : NSObject
 
 +(void)bootstrap:(NSURL*)jsCodeLocation launchOptions:(NSDictionary *)launchOptions;
 
++ (void)registerExternalComponent:(NSString *)name callback:(RNNExternalViewCreator)callback;
+
 @end

lib/ios/ReactNativeNavigation.m

 #import "ReactNativeNavigation.h"
 
-#import <UIKit/UIKit.h>
 #import <React/RCTBridge.h>
 #import <React/RCTUIManager.h>
 
 	[[ReactNativeNavigation sharedInstance] bootstrap:jsCodeLocation launchOptions:launchOptions];
 }
 
++ (void)registerExternalComponent:(NSString *)name callback:(RNNExternalViewCreator)callback {
+	[[ReactNativeNavigation sharedInstance].bridgeManager registerExternalComponent:name callback:callback];
+}
+
 # pragma mark - instance
 
 + (instancetype) sharedInstance {

playground/ios/playground/AppDelegate.m

 #import "AppDelegate.h"
+#import "RNNCustomViewController.h"
 
 // **********************************************
 // *** DON'T MISS: THE NEXT LINE IS IMPORTANT ***
 	NSURL *jsCodeLocation = [[RCTBundleURLProvider sharedSettings] jsBundleURLForBundleRoot:@"index.ios" fallbackResource:nil];
 	[ReactNativeNavigation bootstrap:jsCodeLocation launchOptions:launchOptions];
 	
+	[ReactNativeNavigation registerExternalComponent:@"RNNCustomComponent" callback:^UIViewController *{
+		return [[RNNCustomViewController alloc] init];
+	}];
+	
 	/*
 	// original RN bootstrap - remove this part
 	RCTRootView *rootView = [[RCTRootView alloc] initWithBundleURL:jsCodeLocation