AppDelegate.m

#import <Flutter/Flutter.h>
#import "GeneratedPluginRegistrant.h"
#import <UXCam/UXCam.h> // Don't forget to import

@implementation AppDelegate
- (BOOL)application:(UIApplication*)application didFinishLaunchingWithOptions:(NSDictionary*)launchOptions {
  FlutterViewController* controller = (FlutterViewController*)self.window.rootViewController;

  FlutterMethodChannel* uxcamChannel = [FlutterMethodChannel
                                          methodChannelWithName:@"com.ur.app/uxcam" // Your methodChannel name
                                          binaryMessenger:controller];

  [uxcamChannel setMethodCallHandler:^(FlutterMethodCall* call, FlutterResult result) {
    if ([@"init" isEqualToString:call.method]) {
      NSString *userAPIKey = call.arguments[@"apiKey"];
      [UXCam startWithKey:userAPIKey];
    }
  }];

  [GeneratedPluginRegistrant registerWithRegistry:self];
  return [super application:application didFinishLaunchingWithOptions:launchOptions];
}