CODEWITHSUNDEEP
iosreact-native
angular_learner
angular_learner

Reputation: 671

React Native - send data from native to javascript/bridging

I'm very new to React Native (iOS) and I have read a lot about Bridging, however I cannot seem to make this working.

I need to be able to send an object/string from AppDelegate to JavaScript. My AppDelegate returns a UserName which is retrieved by a native code in one of my methods inside AppDelegate.

I tried to use in AppDelegate.m

#import "RCTBridge.h"
#import "RCTEventDispatcher.h"

and then

@synthesize bridge = _bridge;

and inside my method

  NSString *eventName = notification.userInfo[@"name"];
  [self.bridge.eventDispatcher sendAppEventWithName:@"EventReminder"
                                               body:@{@"name": eventName}];

but none of the above works and I'm getting errors. Do I need to do anything to AppDelegate.h as well?

Can anyone please help me? What is the easiest way to sent data from native to javascript?

UPDATE:

I found a workaround, but I don't think it's effective as I'm calling RCTRootView twice. First to load the app with initialProperties nil, like this:

- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions
{
  NSURL *jsCodeLocation;


 jsCodeLocation = [NSURL URLWithString:@"http://localhost:8081/index.ios.bundle?platform=ios&dev=true"];



  RCTRootView *rootView = [[RCTRootView alloc] initWithBundleURL:jsCodeLocation
                                                      moduleName:@"myApp"
                                               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];

  [self getUsername];

}

And for the second time when I retrieve a UserName I then update initialProperties like this:

-(void) getUsername {

    //3rd party code to retrieve the username

            NSString *username = username

      NSURL *jsCodeLocation;

      jsCodeLocation = [NSURL URLWithString:@"http://localhost:8081/index.ios.bundle?platform=ios&dev=true"];

      RCTBridge *bridge = [[RCTBridge alloc] initWithBundleURL:jsCodeLocation moduleProvider:nil launchOptions:nil];

      RCTRootView *rootView = [[RCTRootView alloc] initWithBridge:bridge
                                                       moduleName:@"myApp"
                                                initialProperties: @{@"username" : username}];



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


}

By doing the way above I'm then able to send and receive username via this.props in JavaScript.

But like I said, I'm not sure this is an effective way as I'm calling RCTRootView twice.

Any help is appreciated please.

Upvotes: 1

Views: 2483

Answers (1)

rmevans9
rmevans9

Reputation: 5643

You could, instead of trying to put it in the initial launch code on the iOS side, put it in a Native Module that you export a function to return the information from. See React Natives official documentation on it: https://facebook.github.io/react-native/docs/native-modules-ios.html

Upvotes: 2

Related Questions