RCTViewManager and RCTUIManager

1. RCTViewManager

1.1 RCTViewManager 实现了接口RCTBridgeModule

1 @interface RCTViewManager : NSObject

1.2 宏RCT_EXPORT_VIEW_PROPERTY

from file RCTViewManager.m

1 RCT_EXPORT_VIEW_PROPERTY(accessibilityLabel, NSString)

以上宏展开为:

1 // RCT_EXPORT_VIEW_PROPERTY(accessibilityLabel, NSString) 2 + (NSString *)getPropConfigView_accessibilityLabel { return @"NSString"; } 3 - (void)set_accessibilityLabel:(id)json forView:(UIView *)view withDefaultView:(UIView *)defaultView 4 { if ((json && !RCTSetProperty(view, @"accessibilityLabel", @selector(NSString:), json)) 5       || (!json && !RCTCopyProperty(view, defaultView, @"accessibilityLabel"))) 6   { 7     do { 8       if (RCTLogLevelError >= RCTLogLevelMustFix) { 9         do {10           BOOL pass = ((__objc_no) != 0);11           if (1 && !pass){12               [[NSAssertionHandler currentHandler] handleFailureInFunction:@(__func__)13                                                                       file:@("/Users/XiaoKL/react-native/AwesomeProject/node_modules/react-native/React/Views/RCTViewManager.m")14                                                                 lineNumber:9415                                                                description:@"%@ does not have setter for `%s` property", [view class], "accessibilityLabel"];16           }17           _RCTAssertFormat(pass, "/Users/XiaoKL/react-native/AwesomeProject/node_modules/react-native/React/Views/RCTViewManager.m",18                            94, __func__,19                            @"%@ does not have setter for `%s` property",20                            [view class], "accessibilityLabel");21         } while (0);22       }23     _RCTLogFormat(RCTLogLevelError, "/Users/XiaoKL/react-native/AwesomeProject/node_modules/react-native/React/Views/RCTViewManager.m", 94, @"%@ does not have setter for `%s` property",24                   [view class], "accessibilityLabel");25     } while (0);26   }27 }

3. RCTBridgeModule接口

1 /**2  * Provides the interface needed to register a bridge module.3  */4 @protocol RCTBridgeModule

RCTBridgeModule: 定义注册一个“bridge module”所需要的接口。

bridge module: 实现接口RCTBridgeModule的类被称为“bridge module”, 这些模块可以被注册到 RCTBridge 中。

3.1 RCTBridgeModule.h中提供的宏定义

宏	宏定义以及描述
RCT_EXPORT_MODULE(js_name)	#define RCT_EXPORT_MODULE(js_name) \ RCT_EXTERN void RCTRegisterModule(Class); \ + (NSString *)moduleName { return @#js_name; } \ + (void)load { RCTRegisterModule([self class]); }
RCT_EXPORT_METHOD(method)	#define RCT_EXPORT_METHOD(method) \ RCT_REMAP_METHOD(, method)
RCT_REMAP_METHOD(js_name, method)	#define RCT_REMAP_METHOD(js_name, method) \ RCT_EXTERN_REMAP_METHOD(js_name, method) \ - (void)method
RCT_EXTERN_MODULE(objc_name, objc_supername)	#define RCT_EXTERN_MODULE(objc_name, objc_supername) \ RCT_EXTERN_REMAP_MODULE(, objc_name, objc_supername)
RCT_EXTERN_REMAP_MODULE(js_name, objc_name, objc_supername)	#define RCT_EXTERN_REMAP_MODULE(js_name, objc_name, objc_supername) \ objc_name : objc_supername \ @end \ @interface objc_name (RCTExternModule) <RCTBridgeModule> \ @end \ @implementation objc_name (RCTExternModule) \ RCT_EXPORT_MODULE(js_name)
RCT_EXTERN_METHOD(method)	#define RCT_EXTERN_METHOD(method) \ RCT_EXTERN_REMAP_METHOD(, method)
RCT_EXTERN_REMAP_METHOD(js_name, method)	#define RCT_EXTERN_REMAP_METHOD(js_name, method) \ + (NSArray *)RCT_CONCAT(__rct_export__, RCT_CONCAT(js_name, RCT_CONCAT(__LINE__, __COUNTER__))) { \ return @[@#js_name, @#method]; \ } \

A): RCT_EXPORT_MODULE(js_name): 将BridgeModule注册到bridge中。该宏依赖函数:

RCTRegisterModule(), 下面看一下该函数的实现: (RCTBridge.m)

1 void RCTRegisterModule(Class moduleClass) 2 { 3   static dispatch_once_t onceToken; 4   dispatch_once(&onceToken, ^{ 5     RCTModuleClasses = [[NSMutableArray alloc] init]; 6   }); 7  8   RCTAssert([moduleClass conformsToProtocol:@protocol(RCTBridgeModule)], // 1 9             @"%@ does not conform to the RCTBridgeModule protocol",10             NSStringFromClass(moduleClass));11 12   // Register module13   [RCTModuleClasses addObject:moduleClass];14 }

RCTRegisterModule()仅仅是将Class对象添加到了一个数组类型的静态变量RCTModuleClasses中.

1: “bridge module” 必须实现接口 RCTBridgeModule 。

RCT_EXPORT_MODULE(js_name)

"The optional js_name argument will be used as the JS module name. If omitted, the JS module name will

match the Objective-C class name. "

B): RCT_EXPORT_METHOD(method) 宏　　

Wrap the parameter line of your method implementation with this macro to

expose it to JS.

用宏 RCT_EXPORT_METHOD() 来处理要导出到JS中的接口:

1 RCT_EXPORT_METHOD(createTimer:(NSNumber *)callbackID2                   duration:(NSTimeInterval)jsDuration3                   jsSchedulingTime:(NSDate *)jsSchedulingTime4                   repeats:(BOOL)repeats)

以上宏 RCT_EXPORT_METHOD()展开为:

1 + (NSArray *)__rct_export__1720 { return @[@"", @"createTimer:(NSNumber *)callbackID duration:(NSTimeInterval)jsDuration jsSchedulingTime:(NSDate *)jsSchedulingTime repeats:(BOOL)repeats"]; } - (void)createTimer:(NSNumber *)callbackID duration:(NSTimeInterval)jsDuration jsSchedulingTime:(NSDate *)jsSchedulingTime repeats:(BOOL)repeats

导入到JS的接口为: "NativeModules.ModuleName.createTimer(number)", 只有Selector第一个:以前的部分。

TODO: JavaScript Promise

C): RCT_REMAP_METHOD(js_name, method) 宏

该宏和RCT_EXPORT_METHOD(method)类似, 只不过通过该宏可以指定导入到JS的接口名称。

D): 宏 RCT_EXTERN_MODULE 和 RCT_EXTERN_REMAP_MODULE

RCT_EXTERN_MODULE(objc_name, objc_supername)

RCT_EXTERN_REMAP_MODULE(js_name, objc_name, objc_supername)

"Use this macro in a private Objective-C implementation file to automatically register an

external module with the bridge when it loads." 'private Object-C implementation'是指Objective-C中的类别(category)。

1   2 /* MyModuleExport.m: 3  * 4  *   #import "RCTBridgeModule.h" 5  * 6  *   @interface RCT_EXTERN_MODULE(MyModule, NSObject) 7  * 8  *   RCT_EXTERN_METHOD(doSomething:(NSString *)string withFoo:(NSInteger)a bar:(NSInteger)b) 9  *10  *   @end11  *12  * This will now expose MyModule and the method to JavaScript via13  * `NativeModules.MyModule.doSomething`14  */15 #define RCT_EXTERN_MODULE(objc_name, objc_supername) \16   RCT_EXTERN_REMAP_MODULE(, objc_name, objc_supername)17 18 /**19  * Like RCT_EXTERN_MODULE, but allows setting a custom JavaScript name.20  */21 #define RCT_EXTERN_REMAP_MODULE(js_name, objc_name, objc_supername) \22   objc_name : objc_supername \23   @end \24   @interface objc_name (RCTExternModule) 
     
       \25   @end \26   @implementation objc_name (RCTExternModule) \27   RCT_EXPORT_MODULE(js_name)

E: 宏RCT_EXTERN_METHOD 和 RCT_EXTERN_REMAP_METHOD

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