How to bridge React Native Promise to Swift

Question

Hi fellow software enthousiasts,

I am currently working on a React native project for which I need to add some logic which has been written in swift. I am able to trigge

Answer 1

Taken from the answers at Got "is not a recognized Objective-C method" when bridging Swift to React-Native; the fact that it doesn't work, is because of the difference in the first argument labels.

To make it work with your initial code you should write the first argument of your Swift to be without a name, like this:

@objc
func loginWithEmail(_ resolve: RCTPromiseResolveBlock, rejecter reject: RCTPromiseRejectBlock) -> Void {
    //   the trick  ^
    resolve("This method is no longer troublesome")
}

Answer 2

Adding so that the complete solution is shown

.m - note that the resolve parameter is not "named"

RCT_EXTERN_METHOD(loginWithEmail: (RCTPromiseResolveBlock)resolve
                                  rejecter:(RCTPromiseRejectBlock)reject)

.swift - same as @Koen

@objc func loginWithEmail(_ resolve: @escaping RCTPromiseResolveBlock,
                            rejecter reject: @escaping RCTPromiseRejectBlock ) -> Void {}

Answer 3

I did eventually come up with a solution. It is not exactly like React native people intended it I believe, but it works. So i can continue and maybe someone else is set on the right track with my solution. Although, please post the way it is supposed to be.

So I decided to start with the Objective-C way first. So I created a .h file for my module.

MyLoginBridge.h

#import <React/RCTBridgeModule.h>

@interface MyLoginBridge : NSObject <RCTBridgeModule>
@end

Then alter the .m file

#import "MyLoginBridge.h"
#import "MyProject-Swift.h" // Include the swift header manually

@implementation MyLoginBridge

RCT_EXPORT_MODULE(MyCustomLoginJSName);

RCT_EXPORT_METHOD(loginWithEmail:(RCTPromiseResolveBlock)resolve   rejecter:(RCTPromiseRejectBlock)reject)
{
    // Manually init the module and call swift function
    MyLoginModule* module = [[MyLoginModule alloc] init];
    [module loginWithEmailWithResolver:resolve rejecter:reject];
}

@end

The swift file and the bridging header remained the same. This works.