Reactnative-iOS回调Javascript

Reactnative可以调用原生模块，原生模块也可以给JavaScript发送事件通知.最好的方法是继承RCTEventEmitter.自定义继承自PushEventEmitter的子类RCTEventEmitter.

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

@interface PushEventEmitter : RCTEventEmitter <RCTBridgeModule>

- (void)addEventReminderReceived:(NSNotification *)notification;

@end

实现supportedEvents方法

#import "PushEventEmitter.h"

@implementation PushEventEmitter

+ (id)allocWithZone:(NSZone *)zone {
    static PushEventEmitter *sharedInstance = nil;
    static dispatch_once_t onceToken;
    dispatch_once(&onceToken, ^{
        sharedInstance = [super allocWithZone:zone];
    });
    return sharedInstance;
}

RCT_EXPORT_MODULE();

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

- (void)addEventReminderReceived:(NSNotification *)notification {
    [self sendEventWithName:@"EventReminder" body:@{@"name": @"FlyElephant"}];
}

@end

React native 设置:

import {
    NativeModules,
    NativeEventEmitter,
} from 'react-native';

const PushEventEmitter  = NativeModules.PushEventEmitter;

const emitterManager = new NativeEventEmitter(PushEventEmitter);

订阅通知和移除通知:

    componentDidMount() {
        subscription = emitterManager.addListener(
            'EventReminder',
            (reminder) => console.log('JavaScript接收到通知:'+reminder.name)
        );

    }
    componentWillUnmount(){
        subscription.remove();// 移除通知
    }

调用测试:

    PushEventEmitter *eventEmitter = [PushEventEmitter allocWithZone:nil];
    [eventEmitter addEventReminderReceived:nil];