Fabric: RCTComponentViewRegistry

Summary:
A registry for components. The registry allows to refer to component view instance by react tag.
It also has recycle-pool-like interface (and eventually the pool will be implemented).

Reviewed By: mdvacca

Differential Revision: D7507519

fbshipit-source-id: ed74203fb4d0694490b0dc23aae0aa067b3fc55b

React/Fabric/Mounting/RCTComponentViewRegistry.h

@@ -0,0 +1,48 @@
+/**
+ * Copyright (c) 2015-present, Facebook, Inc.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ */
+
+#import <UIKit/UIKit.h>
+
+#import <React/RCTComponentViewProtocol.h>
+
+NS_ASSUME_NONNULL_BEGIN
+
+/**
+ * Registry of native component views.
+ * Provides basic functionality for allocation, recycling, and querying (by tag) native view instances.
+ */
+@interface RCTComponentViewRegistry : NSObject
+
+/**
+ * Returns a native view instance from the recycle pool (or create)
+ * for given `componentName` and with given `tag`.
+ * #RefuseSingleUse
+ */
+- (UIView<RCTComponentViewProtocol> *)dequeueComponentViewWithName:(NSString *)componentName
+                                                               tag:(ReactTag)tag;
+
+/**
+ * Puts a given native component view to the recycle pool.
+ * #RefuseSingleUse
+ */
+- (void)enqueueComponentViewWithName:(NSString *)componentName
+                                 tag:(ReactTag)tag
+                       componentView:(UIView<RCTComponentViewProtocol> *)componentView;
+
+/**
+ * Returns a native component view by given `tag`.
+ */
+- (UIView<RCTComponentViewProtocol> *)componentViewByTag:(ReactTag)tag;
+
+/**
+ * Returns `tag` assosiated with given `componentView`.
+ */
+- (ReactTag)tagByComponentView:(UIView<RCTComponentViewProtocol> *)componentView;
+
+@end
+
+NS_ASSUME_NONNULL_END

React/Fabric/Mounting/RCTComponentViewRegistry.mm

@@ -0,0 +1,59 @@
+/**
+ * Copyright (c) 2015-present, Facebook, Inc.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ */
+
+#import "RCTComponentViewRegistry.h"
+
+#import <Foundation/NSMapTable.h>
+#import <React/RCTAssert.h>
+
+@implementation RCTComponentViewRegistry {
+  NSMapTable<id, UIView<RCTComponentViewProtocol> *> *_registry;
+}
+
+- (instancetype)init
+{
+  if (self = [super init]) {
+    _registry = [NSMapTable mapTableWithKeyOptions:NSPointerFunctionsIntegerPersonality | NSPointerFunctionsOpaqueMemory
+                                      valueOptions:NSPointerFunctionsObjectPersonality];
+  }
+
+  return self;
+}
+
+- (UIView<RCTComponentViewProtocol> *)dequeueComponentViewWithName:(NSString *)componentName
+                                                               tag:(ReactTag)tag
+{
+  RCTAssertMainQueue();
+  // This is temporary approach.
+  NSString *className = [NSString stringWithFormat:@"RCT%@ComponentView", componentName];
+  UIView<RCTComponentViewProtocol> *componentView = [[NSClassFromString(className) alloc] init];
+  componentView.tag = tag;
+  [_registry setObject:componentView forKey:(__bridge id)(void *)tag];
+  return componentView;
+}
+
+- (void)enqueueComponentViewWithName:(NSString *)componentName
+                                 tag:(ReactTag)tag
+                       componentView:(UIView<RCTComponentViewProtocol> *)componentView
+{
+  RCTAssertMainQueue();
+  [_registry removeObjectForKey:(__bridge id)(void *)tag];
+}
+
+- (UIView<RCTComponentViewProtocol> *)componentViewByTag:(ReactTag)tag
+{
+  RCTAssertMainQueue();
+  return [_registry objectForKey:(__bridge id)(void *)tag];
+}
+
+- (ReactTag)tagByComponentView:(UIView<RCTComponentViewProtocol> *)componentView
+{
+  RCTAssertMainQueue();
+  return componentView.tag;
+}
+
+@end