ReactNative与iOS原生交互方式汇总

2018-09-10 本文已影响27人 FanChason

前言

最近用RN开发SDK，涉及RN与iOS各种交互。

有些交互比如用iOS原生切换多个RN页面，以及iOS调用RN的方法，按照网上的方法调不通，一度不知如何是好，网上资料比较少。

于是自己看RN源码分析得出一些方法。
如有问题欢迎指正，有更好的思路方法欢迎分享。

一、 iOS 调用ReactNative

1,打开一个ReactNative页面

比如react-native init RNInteractionWithiOS 创建一个应用之后就会自动在 RNInteractionWithiOS->ios->RNInteractionWithiOS->AppDelegate.m中生成打开一个ReactNative页面的代码。核心代码如下：

 NSURL *jsCodeLocation;

 jsCodeLocation = [[RCTBundleURLProvider sharedSettings] jsBundleURLForBundleRoot:@"index" fallbackResource:nil];

 RCTRootView *rootView = [[RCTRootView alloc] initWithBundleURL:jsCodeLocation
                                                     moduleName:@"RNInteractionWithiOS"
                                              initialProperties:nil
                                                  launchOptions:launchOptions];
 rootView.backgroundColor = [[UIColor alloc] initWithRed:1.0f green:1.0f blue:1.0f alpha:1];

 self.window = [[UIWindow alloc] initWithFrame:[UIScreen mainScreen].bounds];
 UIViewController *rootViewController = [UIViewController new];
 rootViewController.view = rootView;
 self.window.rootViewController = rootViewController;
 [self.window makeKeyAndVisible];

2,多个ReactNative页面切换（尽量在RN内实现）

这个有点难度，当时还研究了半天，几乎没有资料可参考

RN核心代码：
在index.js中

AppRegistry.registerComponent("App", () => App);
AppRegistry.registerComponent("App2", () => App2);

iOS中OC核心代码：
- 设置RCTBridge的代理
- 实现代理方法- (NSURL *)sourceURLForBridge:(RCTBridge *)bridge;
- 最关键的：通常情况下我们会使用initWithBundleURL创建一个RCTRootView，此处必须使用initWithBridge创建RCTRootView

#import "ViewController.h"
#import <React/RCTBundleURLProvider.h>
#import <React/RCTRootView.h>

@interface ViewController ()<RCTBridgeDelegate>
@property (nonatomic, strong) RCTBridge *bridge;

@end

@implementation ViewController

- (NSURL *)sourceURLForBridge:(RCTBridge *)bridge {
  return [NSURL URLWithString:@"http://127.0.0.1:8081/index.bundle?platform=ios"];// 模拟器
}

- (void)viewDidLoad {
    [super viewDidLoad];
  _bridge = [[RCTBridge alloc] initWithDelegate:self launchOptions:nil];
}

#define RNBounds CGRectMake(0, 0, UIScreen.mainScreen.bounds.size.width-50, UIScreen.mainScreen.bounds.size.height/2.f)

- (IBAction)openRNOne {
  [self removeRNPage];
  [self loadRNView:@"App"];
}

- (IBAction)openRNTwo {
  [self removeRNPage];
  [self loadRNView:@"App2"];
}

- (IBAction)removeRNPage {
  [self.view.subviews enumerateObjectsUsingBlock:^(__kindof UIView * _Nonnull obj, NSUInteger idx, BOOL * _Nonnull stop) {
    if ([obj isKindOfClass:[RCTRootView class]]) {
      [obj removeFromSuperview];
      return;
    }
  }];
}

- (void)loadRNView:(NSString *)moduleName {
  RCTRootView *rnView2 = [[RCTRootView alloc] initWithBridge:_bridge
                                                  moduleName:moduleName
                                           initialProperties:nil];
  rnView2.bounds = RNBounds;
  rnView2.center = self.view.center;
  [self.view addSubview:rnView2];
}

3，iOS调用RN(分是否传参数)

RN核心代码

  componentWillMount() {
      DeviceEventEmitter.addListener('EventInit', (msg) => {
          let receive = "EventInit: " + msg;
          console.log(receive);
          this.setState({notice: receive});
      });

      DeviceEventEmitter.addListener('EventLogin', (msg) => {
          let receive = "EventLogin: " + msg;
          console.log(receive);
          this.setState({notice: receive});
      });
  }

iOS核心代码：
- 创建的iOS交互类要引用#import<React/RCTBridgeModule.h> 和#import <React/RCTEventEmitter.h>,继承RCTEventEmitter，并遵守RCTBridgeModule
- 很关键的：交互类要设置bridge为当前RCTRootView的bridge，[[ReactInteraction shareInstance] setValue:rnView.bridge forKey:@"bridge"];

ReactInteraction.h文件

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

@interface ReactInteraction : RCTEventEmitter <RCTBridgeModule>
+ (instancetype)shareInstance;
- (void)init:(NSString *)parameter;
- (void)login;
@end

ReactInteraction.m文件


#import "ReactInteraction.h"

#define INIT @"EventInit"
#define LOGIN @"EventLogin"

@implementation ReactInteraction
static ReactInteraction *instance = nil;

RCT_EXPORT_MODULE();
+ (instancetype)shareInstance {
  static dispatch_once_t onceToken;
  dispatch_once(&onceToken, ^{
    instance = [[self alloc] init];
  });
  return instance;
}

- (NSArray<NSString *> *)supportedEvents
{
  return @[INIT,LOGIN];
}

RCT_EXPORT_METHOD(init:(NSString *)msg) {
  [self.bridge enqueueJSCall:@"RCTDeviceEventEmitter"
                      method:@"emit"
                        args:@[INIT, msg]
                  completion:NULL];
}

RCT_EXPORT_METHOD(login) {
  [self.bridge enqueueJSCall:@"RCTDeviceEventEmitter"
                      method:@"emit"
                        args:@[LOGIN]
                  completion:NULL];
}

@end

二、ReactNative调用iOS

RN核心代码：

import {NativeModules} from 'react-native';
const NativeInteraction = NativeModules.NativeInteraction;

iOS核心代码：
- 注意点1：RCT_EXPORT_METHOD与RCT_REMAP_METHOD宏定义的使用区别（个人总结，有不对请指正）
  - RCT_EXPORT_METHOD：用于仅有一个参数或回调
  - RCT_REMAP_METHOD：用于有多个参数或（和）多个回调
    （了解更多可以看RN宏定义源码1，下面👇贴出关键两句)
- 注意点2：iOS回调方式有两种
  - callback(@[jsonString]); ((RCTPromiseResolveBlock)resolver)
  - Promise方式：_resolveBlock(@[jsonString]); ((RCTResponseSenderBlock)callback) （了解更多看RN源码2）

源码1：

#define RCT_REMAP_METHOD(js_name, method) \
  _RCT_EXTERN_REMAP_METHOD(js_name, method, NO) \
  - (void)method RCT_DYNAMIC;

#define RCT_EXPORT_METHOD(method) \
  RCT_REMAP_METHOD(, method)

源码2：

typedef void (^RCTResponseSenderBlock)(NSArray *response);
typedef void (^RCTResponseErrorBlock)(NSError *error);
typedef void (^RCTPromiseResolveBlock)(id result);
typedef void (^RCTPromiseRejectBlock)(NSString *code, NSString *message, NSError *error);

1,无参数回调

RN核心代码：

    NativeInteraction.RNTransferIOS();

iOS核心代码：

RCT_EXPORT_METHOD(RNTransferIOS) {
  NSLog(@"RN调用iOS");
}

2,有多个参数

RN核心代码：

 NativeInteraction.RNTransferIOSWithParameter('{\'para1\':\'rndata1\',\'para2\':\'rndata2\'}');

iOS核心代码：

RCT_EXPORT_METHOD(RNTransferIOSWithParameter:(NSString *)logString) {
  NSLog(@"来自RN的数据：%@",logString);
}

3,有回调

RN核心代码：

    NativeInteraction.RNTransferIOSWithCallBack((data) => {
      this.setState({notice: data});
    });

iOS核心代码：

RCT_EXPORT_METHOD(RNTransferIOSWithCallBack:(RCTResponseSenderBlock)callback) {
  callback(@[[NSString stringWithFormat:@"来自iOS Native的数据：%@",TestNativeJsonData]]);
}

4,有多个参数多个回调

RN核心代码：

 NativeInteraction.RNTransferIOSWithParameterAndCallBack('rndata1','rndata2').then(result =>{
      let jsonString = JSON.stringify(result);
      this.setState({notice: jsonString});
    }).catch(error=>{
    });

iOS核心代码：

{
  RCTPromiseResolveBlock _resolveBlock;
  RCTPromiseRejectBlock _rejectBlock;
}
RCT_REMAP_METHOD(RNTransferIOSWithParameterAndCallBack, para1:(NSString *)para1 para2:(NSString *)para2 resolver:(RCTPromiseResolveBlock)resolver rejecter:(RCTPromiseRejectBlock)reject) {
  NSLog(@"来自RN的数据：para1——%@， para2——%@",para1, para2);

  _resolveBlock=resolver;
  _rejectBlock=reject;
  NSString *jsonString = TestNativeJsonData;
  _resolveBlock(@[jsonString]);
}

如上有问题欢迎各路大神留言指正，写博客不容易，大家相互学习。