kmpdfkit_demo/ios/Runner/AppDelegate.swift

import UIKit
import Flutter

@UIApplicationMain
@objc class AppDelegate: FlutterAppDelegate {
  override func application(
    _ application: UIApplication,
    didFinishLaunchingWithOptions launchOptions: [UIApplication.LaunchOptionsKey: Any]?
  ) -> Bool {
      let controller:FlutterViewController = window?.rootViewController as! FlutterViewController
      GeneratedPluginRegistrant.register(with: self)
      PDFSDKInfoPlugin.init(messenger: controller.binaryMessenger)
      weak var registrar = self.registrar(forPlugin: "plugin-name")

      let factory = PDFLNativeViewFactory(messenger: registrar!.messenger())
      self.registrar(forPlugin: "<plugin-name>")!.register(
          factory,
          withId: "com.compdfkit.pdf.flutter.pdfview")
      
    return super.application(application, didFinishLaunchingWithOptions: launchOptions)
  }
}