Issue 1:
#I get an Error if I wan't to push an MaterialPage.

Screenshot

Code

import 'package:flutter/material.dart';

void main() {
runApp(MaterialApp(
title: 'Navigation Basics',
home: FirstScreen(),
));
}

class FirstScreen extends StatelessWidget {
@override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(
title: Text('First Screen'),
),
body: Center(
child: RaisedButton(
child: Text('Launch screen'),
onPressed: () {
Navigator.push(
context,
new MaterialPageRoute(
builder: (BuildContext context) => new SecondScreen()),
);
},
),
),
);
}
}

class SecondScreen extends StatelessWidget {
@override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(
title: Text("Second Screen"),
),
body: Center(
child: RaisedButton(
onPressed: () {
Navigator.pop(context);
},
child: Text('Go back!'),
),
),
);
}
}

Error

Launching lib/main.dart on iPhone X in debug mode...
compiler message: file:///Users/abuder/flutter/packages/flutter/lib/src/widgets/navigator.dart:815:95: Error: Duplicated parameter name 'context'.
compiler message: static Future<T> push<T extends Object>(BuildContext context, Route<T> route, {BuildContext context}) {
compiler message: ^^^^^^^
compiler message: file:///Users/abuder/flutter/packages/flutter/lib/src/widgets/navigator.dart:815:56: Context: Other parameter named 'context'.
compiler message: static Future<T> push<T extends Object>(BuildContext context, Route<T> route, {BuildContext context}) {
compiler message: ^^^^^^^
Compiler failed on /Users/abuder/projects/flutter/butterfly_member/lib/main.dart
Error launching application on iPhone X.
Exited (sigterm)

Issue 2:
I am trying to add flutter to existing ios app. So before adding to the production app i decided to bring it some demo app. The flutter app independent is working fine in both android and ios. Even in the existing ios app its working fine except the plugin. I followed the tutorial and ran all commands like

flutter run,flutter clean but nothing made it to work in the existing app. when doing the pod install it's showing that it's adding the plugin and fetching the related files for it but when I am using the app its throwing the below error

2018-11-01 22:31:44.193838+0530 EgluDiscoverIOS[8186:2926742] flutter: Observatory listening on http://127.0.0.1:53871/
2018-11-01 22:31:49.533104+0530 EgluDiscoverIOS[8186:2926733] [VERBOSE-2:shell.cc(188)] Dart Error: Unhandled exception:
MissingPluginException(No implementation found for method canLaunch on channel plugins.flutter.io/url_launcher)
#0 MethodChannel.invokeMethod (package:flutter/src/services/platform_channel.dart:278:7)
<asynchronous suspension>
#1 canLaunch (package:url_launcher/url_launcher.dart:88:25)
<asynchronous suspension>
#2 AssistantWidget.build._launchUrl (package:eglu_discover_final/assistant.dart:90:17)
<asynchronous suspension>
#3 _InkResponseState._handleTap (package:flutter/src/material/ink_well.dart:507:14)
#4 _InkResponseState.build.<anonymous closure> (package:flutter/src/material/ink_well.dart:562:30)
#5 GestureRecognizer.invokeCallback (package:flutter/src/gestures/recognizer.dart:102:24)
#6 TapGestureRecognizer._checkUp (package:flutter/src/gestures/tap.dart:242:9)
#7 TapGestureRecognizer.acceptGesture (package:flutter/src/gestures/tap.dart:204:7)
#8 GestureArenaManager.sweep (package:flutter/src/gestures/arena.dart:156:27)
#9 _WidgetsFlutterBinding&BindingBase&GestureBinding.handleEvent (package:flutter/src/gestures/binding.dart:143:20)
#10 _WidgetsFlutterBinding&BindingBase&GestureBinding.dispatchEvent (package:flutter/src/gestures/binding.dart:117:22)
#11 _WidgetsFlutterBinding&BindingBase&GestureBinding._handlePointerEvent (package:flutter/src/gestures/binding.dart:97:7)
#12 _WidgetsFlutterBinding&BindingBase&GestureBinding._flushPointerEventQueue (package:flutter/src/gestures/binding.dart:60:7)
#13 _WidgetsFlutterBinding&BindingBase&GestureBinding._handlePointerDataPacket (package:flutter/src/gestures/binding.dart:44:7)
#14 _invoke1 (dart:ui/hooks.dart:159:13)
#15 _dispatchPointerDataPacket (dart:ui/hooks.dart:113:5)
2018-11-01 22:32:05.187471+0530 EgluDiscoverIOS[8186:2926733] [VERBOSE-2:shell.cc(188)] Dart Error: Unhandled exception:
MissingPluginException(No implementation found for method canLaunch on channel plugins.flutter.io/url_launcher)
#0 MethodChannel.invokeMethod (package:flutter/src/services/platform_channel.dart:278:7)
<asynchronous suspension>
#1 canLaunch (package:url_launcher/url_launcher.dart:88:25)
<asynchronous suspension>
#2 UpdateCard._launchUrl (package:eglu_discover_final/update_card.dart:10:17)
<asynchronous suspension>
#3 _InkResponseState._handleTap (package:flutter/src/material/ink_well.dart:507:14)
#4 _InkResponseState.build.<anonymous closure> (package:flutter/src/material/ink_well.dart:562:30)
#5 GestureRecognizer.invokeCallback (package:flutter/src/gestures/recognizer.dart:102:24)
#6 TapGestureRecognizer._checkUp (package:flutter/src/gestures/tap.dart:242:9)
#7 TapGestureRecognizer.acceptGesture (package:flutter/src/gestures/tap.dart:204:7)
#8 GestureArenaManager.sweep (package:flutter/src/gestures/arena.dart:156:27)
#9 _WidgetsFlutterBinding&BindingBase&GestureBinding.handleEvent (package:flutter/src/gestures/binding.dart:143:20)
#10 _WidgetsFlutterBinding&BindingBase&GestureBinding.dispatchEvent (package:flutter/src/gestures/binding.dart:117:22)
#11 _WidgetsFlutterBinding&BindingBase&GestureBinding._handlePointerEvent (package:flutter/src/gestures/binding.dart:97:7)
#12 _WidgetsFlutterBinding&BindingBase&GestureBinding._flushPointerEventQueue (package:flutter/src/gestures/binding.dart:60:7)
#13 _WidgetsFlutterBinding&BindingBase&GestureBinding._handlePointerDataPacket (package:flutter/src/gestures/binding.dart:44:7)
#14 _invoke1 (dart:ui/hooks.dart:159:13)
#15 _dispatchPointerDataPacket (dart:ui/hooks.dart:113:5)

below is my AppDelegate.swift

import UIKit
import Flutter
import FlutterPluginRegistrant

@UIApplicationMain
class AppDelegate: UIResponder, UIApplicationDelegate,FlutterAppLifeCycleProvider {

let lifeCycleDelegate=FlutterPluginAppLifeCycleDelegate()

func addApplicationLifeCycleDelegate(_ delegate: FlutterPlugin) {
lifeCycleDelegate.add(delegate)
}

var rootFlutterViewController:FlutterViewController? {
let viewController = UIApplication.shared.keyWindow?.rootViewController
if viewController!.isKind(of: FlutterViewController.self) {
return viewController as? FlutterViewController
}
return nil
}

var window: UIWindow?

func application(_ application: UIApplication, didFinishLaunchingWithOptions launchOptions: [UIApplication.LaunchOptionsKey: Any]?) -> Bool {
// Override point for customization after application launch.
if launchOptions == nil {
return true
}else {
GeneratedPluginRegistrant.register(with: self as? FlutterPluginRegistry)
return lifeCycleDelegate.application(application, didFinishLaunchingWithOptions: launchOptions!)
}
}

func applicationWillResignActive(_ application: UIApplication) {
// Sent when the application is about to move from active to inactive state. This can occur for certain types of temporary interruptions (such as an incoming phone call or SMS message) or when the user quits the application and it begins the transition to the background state.
// Use this method to pause ongoing tasks, disable timers, and invalidate graphics rendering callbacks. Games should use this method to pause the game.
lifeCycleDelegate.applicationWillResignActive(application)
}

func applicationDidEnterBackground(_ application: UIApplication) {
// Use this method to release shared resources, save user data, invalidate timers, and store enough application state information to restore your application to its current state in case it is terminated later.
// If your application supports background execution, this method is called instead of applicationWillTerminate: when the user quits.
lifeCycleDelegate.applicationDidEnterBackground(application)
}

func applicationWillEnterForeground(_ application: UIApplication) {
// Called as part of the transition from the background to the active state; here you can undo many of the changes made on entering the background.
lifeCycleDelegate.applicationWillEnterForeground(application)
}

func applicationDidBecomeActive(_ application: UIApplication) {
// Restart any tasks that were paused (or not yet started) while the application was inactive. If the application was previously in the background, optionally refresh the user interface.
lifeCycleDelegate.applicationDidBecomeActive(application)
}

func applicationWillTerminate(_ application: UIApplication) {
// Called when the application is about to terminate. Save data if appropriate. See also applicationDidEnterBackground:.
lifeCycleDelegate.applicationWillTerminate(application)
}

}

I am trying to use this plugin https://pub.dartlang.org/packages/url_launcher