Programatically join Wi-Fi network on iOS with React Native wrapper for NEHotspotConfiguration

example.js

import { Platform, NativeModules } from 'react-native'

const IOSWifiManager = NativeModules.IOSWifiManager

const wifiConnect = (ssid) => (
  IOSWifiManager.connectToSSID(ssid)
)

const wifiConnectProtected = (ssid, password, isWep) => (
  IOSWifiManager.connectToProtectedSSID(ssid, password, isWep)
)

const wifiDisconnect = (ssid) => (
  IOSWifiManager.disconnectFromSSID(ssid)
)

const wifiCurrentSSID = () => (
  IOSWifiManager.currentSSID()
)

const wifiSettingsURL = IOSWifiManager.settingsURL

IOSWifiManager.h

// Created by Rutger Bresjer on 10/10/2017

// Notes:
// - Be sure to enable "Hotspot Configuration" capability for the iOS target
// - Make sure the NetworkExtension framework is linked to the target

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

@interface IOSWifiManager : NSObject <RCTBridgeModule>

@end

IOSWifiManager.m

#import "IOSWifiManager.h"
#import <NetworkExtension/NetworkExtension.h>
#import <SystemConfiguration/CaptiveNetwork.h>
// If using official settings URL
//#import <UIKit/UIKit.h>

@implementation IOSWifiManager
RCT_EXPORT_MODULE();

RCT_EXPORT_METHOD(connectToSSID:(NSString*)ssid
                  resolver:(RCTPromiseResolveBlock)resolve
                  rejecter:(RCTPromiseRejectBlock)reject) {
  
  if (@available(iOS 11.0, *)) {
    NEHotspotConfiguration* configuration = [[NEHotspotConfiguration alloc] initWithSSID:ssid];
    configuration.joinOnce = true;
    
    [[NEHotspotConfigurationManager sharedManager] applyConfiguration:configuration completionHandler:^(NSError * _Nullable error) {
      if (error != nil) {
        reject(@"nehotspot_error", @"Error while configuring WiFi", error);
      } else {
        resolve(nil);
      }
    }];
    
  } else {
    reject(@"ios_error", @"Not supported in iOS<11.0", nil);
  }
}

RCT_EXPORT_METHOD(connectToProtectedSSID:(NSString*)ssid
                  withPassphrase:(NSString*)passphrase
                  isWEP:(BOOL)isWEP
                  resolver:(RCTPromiseResolveBlock)resolve
                  rejecter:(RCTPromiseRejectBlock)reject) {
  
  if (@available(iOS 11.0, *)) {
    NEHotspotConfiguration* configuration = [[NEHotspotConfiguration alloc] initWithSSID:ssid passphrase:passphrase isWEP:isWEP];
    configuration.joinOnce = true;
    
    [[NEHotspotConfigurationManager sharedManager] applyConfiguration:configuration completionHandler:^(NSError * _Nullable error) {
      if (error != nil) {
        reject(@"nehotspot_error", @"Error while configuring WiFi", error);
      } else {
        resolve(nil);
      }
    }];
    
  } else {
    reject(@"ios_error", @"Not supported in iOS<11.0", nil);
  }
}

RCT_EXPORT_METHOD(disconnectFromSSID:(NSString*)ssid
                  resolver:(RCTPromiseResolveBlock)resolve
                  rejecter:(RCTPromiseRejectBlock)reject) {
  
  if (@available(iOS 11.0, *)) {
    [[NEHotspotConfigurationManager sharedManager] getConfiguredSSIDsWithCompletionHandler:^(NSArray<NSString *> *ssids) {
      if (ssids != nil && [ssids indexOfObject:ssid] != NSNotFound) {
        [[NEHotspotConfigurationManager sharedManager] removeConfigurationForSSID:ssid];
      }
      resolve(nil);
    }];
  } else {
    reject(@"ios_error", @"Not supported in iOS<11.0", nil);
  }
  
}

RCT_REMAP_METHOD(currentSSID,
                  resolver:(RCTPromiseResolveBlock)resolve
                  rejecter:(RCTPromiseRejectBlock)reject) {
  
  NSString *kSSID = (NSString*) kCNNetworkInfoKeySSID;
  
  NSArray *ifs = (__bridge_transfer id)CNCopySupportedInterfaces();
  for (NSString *ifnam in ifs) {
    NSDictionary *info = (__bridge_transfer id)CNCopyCurrentNetworkInfo((__bridge CFStringRef)ifnam);
    if (info[kSSID]) {
      resolve(info[kSSID]);
      return;
    }
  }
  
  reject(@"cannot_detect_ssid", @"Cannot detect SSID", nil);
}

- (NSDictionary*)constantsToExport {
  // Officially better to use UIApplicationOpenSettingsURLString
  return @{
           @"settingsURL": @"App-Prefs:root=WIFI"
           };
}

@end

@rbresjer +1

Here's a library that appears to work on a similar way:

https://www.npmjs.com/package/react-native-iot-wifi

Important IOTWifi uses NEHotspotConfigurationManager. To use the NEHotspotConfigurationManager class, you must enable the Hotspot Configuration capability in Xcode.