Question

In the iOS project, I use Objective C to customize a native module, and use sendEventWithName to send an event to the Javascript module.

// MyModule.h
#import <React/RCTBridgeModule.h>

@interface MyModule : NSObject <RCTBridgeModule>

@end

// MyModule.m
#import "MyModule.h"

@implementation MyModule

RCT_EXPORT_MODULE();

- (NSArray<NSString *> *)supportedEvents
{
  return @[@"EventReminder"];
}

- (void)calendarEventReminderReceived:(NSNotification *)notification
{
  NSString *eventName = notification.userInfo[@"name"];
  [self sendEventWithName:@"EventReminder" body:@{@"name": eventName}];
}

@end

But Xcode reports an error.

No visible @interface for 'MyModule' declares the selector 'sendEventWithName:body:'

Solution

sendEventWithName is a method of the RCTEventEmitter class, the MyModule.h needs to inherit RCTEventEmitter instead of NSObject.

// MyModule.h
#import <React/RCTBridgeModule.h>
#import <React/RCTEventEmitter.h>

@interface MyModule : RCTEventEmitter <RCTBridgeModule>

@end