I need to send some data from the native IOS side to the dart side. I am using Channel Method to invoke the method from IOS side but I am getting noting:
Flutter Side:
static const platform = const MethodChannel('samples.flutter.dev/battery');
platform.setMethodCallHandler(myUtilsHandler); // I am calling it in initState
Future<dynamic> myUtilsHandler(MethodCall methodCall) async {
print("myUtilsHandler");
switch (methodCall.method) {
case "someMethod":
print(json.decode(methodCall.arguments));
break;
case 'someMethod2':
print("someMethod2");
break;
default:
print("default");
}
}
Native IOS side:
let controller: FlutterViewController = window?.rootViewController as! FlutterViewController
let batteryChannel = FlutterMethodChannel(name: "samples.flutter.dev/battery",binaryMessenger: controller.binaryMessenger)
batteryChannel.invokeMethod("someMethod", arguments: "someValue")
Note: the other way around is working fine!
I have tested.
In general , use FlutterMethodChannel instance call invokeMethod.
Now I show some test codes based batteryChannel demo.
In AppDelegate add one property
//didFinishLaunchingWithOptions methods
var batteryChannel : FlutterMethodChannel!
batteryChannel = FlutterMethodChannel.init(name: "samples.flutter.dev/battery", binaryMessenger: controller.binaryMessenger)
private func receiveBatteryLevel(result: FlutterResult) {
let device = UIDevice.current;
device.isBatteryMonitoringEnabled = true;
//test send message
sendMessageToFlutter()
if (device.batteryState == UIDevice.BatteryState.unknown) {
result(FlutterError.init(code: "UNAVAILABLE",
message: "Battery info unavailable",
details: nil));
} else {
result(Int(device.batteryLevel * 100));
}
}
private func sendMessageToFlutter(){
DispatchQueue.main.asyncAfter(deadline: DispatchTime.now() + 2) {
self.batteryChannel.invokeMethod("nativeCallSomeFlutterMethod", arguments: nil)
}
}
Now in flutter side , also based batteryChannel demo
class _MyHomePageState extends State<MyHomePage> {
static const platform = const MethodChannel('samples.flutter.dev/battery');
void initState(){
super.initState();
platform.setMethodCallHandler((call) {
print("init state setMethodCallHandler ${call.method}");
});
}
}
after you click Get Battery Level button, 2seconds later ,you can see
init state setMethodCallHandler nativeCallSomeFlutterMethod
Since Dart 2.18, you can also call Objective-C and Swift code directly using Dart's Foreign Function Interface (FFI).
More info: https://medium.com/dartlang/dart-2-18-f4b3101f146c
Related
I am sending Firebase Notification on devices with Xamarin plugin.
This is my configuration : Visual Studio 2022. iOS 15. Xcode 13.
All is working fine in Android devices.
All is working fine in Apple devices except one thing : When the application is in background, the notification is received only when the user open the application.
Here is my code :
public class MVision : UIApplicationDelegate, IUNUserNotificationCenterDelegate, IMessagingDelegate
{
public override bool FinishedLaunching(UIApplication application, NSDictionary launchOptions){
Firebase.Core.App.Configure();
// Messaging.SharedInstance.Self
// Messaging.messaging().delegate = self
Messaging.SharedInstance.Delegate = (IMessagingDelegate)Self;
if (UIDevice.CurrentDevice.CheckSystemVersion(10, 0))
{
// Request Permissions
UNUserNotificationCenter.Current.RequestAuthorization(
UNAuthorizationOptions.Alert | UNAuthorizationOptions.Badge | UNAuthorizationOptions.Sound,
(granted, error) =>
{
// Do something if needed
});
// For iOS 10 display notification (sent via APNS)
UNUserNotificationCenter.Current.Delegate = new MyUNUserNotificationCenterDelegate();
// For iOS 10 data message (sent via FCM)
Messaging.SharedInstance.Delegate = this;
}
else
{
// iOS 9 or before
var allNotificationTypes = UIUserNotificationType.Alert
| UIUserNotificationType.Badge
| UIUserNotificationType.Sound;
var settings = UIUserNotificationSettings
.GetSettingsForTypes(allNotificationTypes, null);
UIApplication.SharedApplication.RegisterUserNotificationSettings(settings);
}
Messaging.SharedInstance.ShouldEstablishDirectChannel = true;
UNUserNotificationCenter.Current.Delegate = new MyUNUserNotificationCenterDelegate();
UIApplication.SharedApplication.RegisterForRemoteNotifications();
The methods are :
[Export("messaging:didReceiveRegistrationToken:")]
public void DidReceiveRegistrationToken(Messaging messaging, string fcmToken)
{
var i = 1;
// var token = Messaging.SharedInstance.FcmToken;
// TODO: If necessary send token to application server.
// Note: This callback is fired at each app startup and whenever a new token is generated.
}
[Export("messaging:didRegisterForRemoteNotificationsWithDeviceToken:")]
public void DidRegisterForRemoteNotificationsWithDeviceToken(UIKit.UIApplication application, Foundation.NSData deviceToken) {
Messaging.SharedInstance.ApnsToken = deviceToken;
}
public override void ReceivedRemoteNotification(UIApplication application, NSDictionary userInfo) { var userInfo1 = userInfo; }
[Export("application:didReceiveNotificationResponse:fetchCompletionHandler:")]
public void DidReceiveNotificationResponse(UNUserNotificationCenter center, UNNotificationResponse response, System.Action completionHandler)
{
completionHandler();
}
[Export("application:didReceiveRemoteNotification:fetchCompletionHandler:")]
public override void DidReceiveRemoteNotification(
UIApplication application,
NSDictionary userInfo,
System.Action<UIBackgroundFetchResult> completionHandler)
{
// If you are receiving a notification message while your app is in the background,
// this callback will not be fired till the user taps on the notification launching the application.
// Except if "content-available" is set to true / 1
// Print full message.
// Console.WriteLine(userInfo);
completionHandler(UIBackgroundFetchResult.NewData);
}
[Export("messaging:didReceiveMessage:")]
public void DidReceiveMessage(Messaging messaging, RemoteMessage remoteMessage)
{
var notification = (NSDictionary)remoteMessage.AppData.ValueForKey(new NSString("notification"));
var title = notification.ValueForKey(new NSString("title"));
var text = notification.ValueForKey(new NSString("body"));
// remotenotification = true;
ScheduleNotification(title.ToString(), text.ToString());
}
//This code is for showing notification
void ScheduleNotification(string title, string body)
{
// Create content
var content = new UNMutableNotificationContent();
content.Title = title;
//content.Subtitle = "Subtitle";
content.Body = body;
content.Badge = 1;
content.CategoryIdentifier = "notification_fv";
content.Sound = UNNotificationSound.Default;
// Fire trigger in one seconds
var trigger = UNTimeIntervalNotificationTrigger.CreateTrigger(1, false);
var requestID = "customNotification";
var request = UNNotificationRequest.FromIdentifier(requestID, content, trigger);
// This is the line that does the trick
UNUserNotificationCenter.Current.AddNotificationRequest(request, (err) => {
if (err != null)
{
// Report error
System.Console.WriteLine("Error: {0}", err);
}
else
{
// Report Success
System.Console.WriteLine("Notification Scheduled: {0}", request);
}
});
}
/* [Export("messaging:didReceiveMessage:")]
public void DidReceiveMessage(Messaging messaging, RemoteMessage remoteMessage)
{
// Handle Data messages for iOS 10 and above.
HandleMessage(remoteMessage.AppData);
var fcmToken = Messaging.SharedInstance.FcmToken;
}*/
[Export("userNotificationCenter:willPresentNotification:withCompletionHandler:")]
public void WillPresentNotification(UNUserNotificationCenter center, UNNotification notification, System.Action<UNNotificationPresentationOptions> completionHandler)
{
SystemSound.Vibrate.PlayAlertSound();
SystemSound.Vibrate.PlaySystemSound();
completionHandler(UNNotificationPresentationOptions.Alert);
}
The notification center delegate class is :
using Foundation;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using UIKit;
using UserNotifications;
namespace MVision.iOS
{
public class MyUNUserNotificationCenterDelegate : UNUserNotificationCenterDelegate
{
bool toggle;
public override void WillPresentNotification(UNUserNotificationCenter center, UNNotification notification, Action<UNNotificationPresentationOptions> completionHandler)
{
if (toggle)
completionHandler(UNNotificationPresentationOptions.Alert);
else
{
// Console.WriteLine(notification);
// completionHandler(UNNotificationPresentationOptions.None);
completionHandler(UNNotificationPresentationOptions.Alert);
}
toggle = !toggle;
}
}
}
I check the info.plist
<key>UIBackgroundModes</key>
<array>
<string>remote-notification</string>
</array>
<key>FirebaseAppDelegateProxyEnabled</key>
<false/>
<key>FirebaseScreenReportingEnabled</key>
<true/>
I also refer to entitlement.developer.plist :
<dict>
<key>aps-environment</key>
<string>development</string>
</dict>
I also parameter my notification with content-available = 1 and mutable-content = 1.
I think that the problem is that "DidReceiveRemoteNotification" is never call neither in background, nor in foreground.
Any Ideas ?
Please also notice : In Xamarin, when you stay in Visual Studio 2019 and you pass to iOS 15, you will not have simulators anymore, please download Visual Studio 2022.
Entitlement.plist does not work on this configuration. You must create Entitlement.developer.plist and refer to is.
I have azure push notification in Xamarin forms. when push notification received I need to open a page in my application. Its working fine in android. In iOS its not working when app is open. When app is in the background its working find in iOS.
This is my App Delegate code
public override void DidReceiveRemoteNotification(UIApplication application, NSDictionary userInfo,
Action<UIBackgroundFetchResult> completionHandler)
{
try
{
UIApplication.SharedApplication.ApplicationIconBadgeNumber = 0;
NSError error;
NSData notification = NSJsonSerialization.Serialize(userInfo["action"], NSJsonWritingOptions.PrettyPrinted, out error);
string notificationString = NSString.FromData(notification, NSStringEncoding.UTF8).ToString();
var NotificationObj = JsonConvert.DeserializeObject<NotificationData>(notificationString);
NotificationService.pushPageName = NotificationObj.Notification[0].PageName.ToString();
NotificationService.pushAppName = NotificationObj.AppName.ToString();
NotificationService.OpenPages = NotificationObj.Notification[0].OpenPage;
NotificationService.Notification = notificationString;
if (UIApplication.SharedApplication.ApplicationState.Equals(UIApplicationState.Active))
{
//App is in foreground. Act on it.
var application1 = new App(NotificationService.pushPageName, NotificationService.pushAppName, NotificationService.Notification);
LoadApplication(application1);
}
else
{
// var application1 = new App(NotificationService.pushPageName, NotificationService.pushAppName, NotificationService.Notification);
// LoadApplication(application1);
}
}
catch (Exception ex)
{
//LogInfo.ReportErrorInfo(ex.Message, ex.StackTrace, "AppDelegate-DidReceiveRemoteNotification");
}
}
after click push notification I need to open splash screen again.
This is App.cs Code
public App(string openPageName, string openAppName,string notification)
{
ServiceContainer.Resolve<IPushNotificationActionService>()
.ActionTriggered += NotificationActionTriggered;
InitMainPage(openPageName, openAppName, notification);
}
private void InitMainPage(string pageName,string appName,string notification)
{
ServiceContainer.Resolve<IPushNotificationActionService>()
.ActionTriggered += NotificationActionTriggered;
PushNotificationActionService.PushNotificationPageName = pageName ;
PushNotificationActionService.PushNotificationAppName = appName;
PushNotificationActionService.PushNotificationMessage = notification;
MainPage = new NavigationPage(new Splash(pageName));
}
All methods are calling and push notification data also loading correctly in iOS. But not navigating to Spalsh Screen. Anyone have an idea to resolve this please help.
If the app is running, we don't need to reload app with LoadApplication , we can directly send message to set MainPage in App.cs .
iOS
if (UIApplication.SharedApplication.ApplicationState.Equals(UIApplicationState.Active))
{
MessagingCenter.Send<object>(this,"Hi");
}
Forms
public App()
{
InitializeComponent();
MainPage = new MainPage();
MessagingCenter.Subscribe<object>(this, "Hi", (obj) => {
MainPage = new NavigationPage(new Splash(pageName));
});
}
I'm using messaging center to fire notification. First one works fine. But the second one is not firing.
MessagingCenter.Subscribe<string>(this, "iOSNotification", (value) =>
{
NotificationDelegate.RegisterNotification("Trip started");
});
MessagingCenter.Subscribe<string>(this, "IosNotMoved", (value) =>
{
NotificationDelegate.RegisterNotification("Would you like to stop trip?");
});
public static void RegisterNotification(string notify)
{
UILocalNotification notification = new UILocalNotification();
notification.FireDate = NSDate.FromTimeIntervalSinceNow(1);
notification.AlertAction = "View Alert";
notification.AlertBody = notify;
UIApplication.SharedApplication.ScheduleLocalNotification(notification);
}
Notification permission should be requested as soon as the app launches by adding the following code to the FinishedLaunching method of the AppDelegate and setting the desired notification type (UNAuthorizationOptions):
...
using UserNotifications;
...
public override bool FinishedLaunching(UIApplication application, NSDictionary launchOptions)
{
....
//after iOS 10
if(UIDevice.CurrentDevice.CheckSystemVersion(10,0))
{
UNUserNotificationCenter center = UNUserNotificationCenter.Current;
center.RequestAuthorization(UNAuthorizationOptions.Alert | UNAuthorizationOptions.Sound | UNAuthorizationOptions.UNAuthorizationOptions.Badge, (bool arg1, NSError arg2) =>
{
});
center.Delegate = new NotificationDelegate();
}
else if(UIDevice.CurrentDevice.CheckSystemVersion(8, 0))
{
var settings = UIUserNotificationSettings.GetSettingsForTypes(UIUserNotificationType.Alert| UIUserNotificationType.Badge| UIUserNotificationType.Sound,new NSSet());
UIApplication.SharedApplication.RegisterUserNotificationSettings(settings);
}
return true;
}
New to iOS 10, an app can handle Notifications differently when it is in the foreground and a Notification is triggered. By providing a UNUserNotificationCenterDelegate and implementing the UserNotificationCentermethod, the app can take over responsibility for displaying the Notification. For example:
using System;
using ObjCRuntime;
using UserNotifications;
namespace xxx
{
public class NotificationDelegate:UNUserNotificationCenterDelegate
{
public NotificationDelegate()
{
}
public override void WillPresentNotification(UNUserNotificationCenter center, UNNotification notification, Action<UNNotificationPresentationOptions> completionHandler)
{
// Do something with the notification
Console.WriteLine("Active Notification: {0}", notification);
// Tell system to display the notification anyway or use
// `None` to say we have handled the display locally.
completionHandler(UNNotificationPresentationOptions.Alert|UNNotificationPresentationOptions.Sound);
}
public override void DidReceiveNotificationResponse(UNUserNotificationCenter center, UNNotificationResponse response, Action completionHandler)
{
// Take action based on Action ID
switch (response.ActionIdentifier)
{
case "reply":
// Do something
break;
default:
// Take action based on identifier
if (response.IsDefaultAction)
{
// Handle default action...
}
else if (response.IsDismissAction)
{
// Handle dismiss action
}
break;
}
// Inform caller it has been handled
completionHandler();
}
}
}
To create and register a Custom Action with the system, use the following code:
public void RegisterNotification(long time)
{
UNUserNotificationCenter center = UNUserNotificationCenter.Current;
//creat a UNMutableNotificationContent which contains your notification content
UNMutableNotificationContent notificationContent = new UNMutableNotificationContent();
notificationContent.Title = "xxx";
notificationContent.Body= "xxxx";
notificationContent.Sound = UNNotificationSound.Default;
UNTimeIntervalNotificationTrigger trigger = UNTimeIntervalNotificationTrigger.CreateTrigger(time, false);
UNNotificationRequest request = UNNotificationRequest.FromIdentifier("FiveSecond", notificationContent, trigger);
center.AddNotificationRequest(request,(NSError obj) =>
{
});
}
When you call this method ,for emample:
RegisterNotification(20);//set the time you want to push notification
The notification will been pushed after 20 seconds,enen if you close your app.
And you can access the link for more information and details: MicroSoft Document
I'm writing nativescript plugin for image picker. I'm finished with part of android. Now, I'm writing code for ios. It's showing image picker dialog, but assigned delegates are not getting triggered. Please check my code below.
import * as application from "tns-core-modules/application";
import * as frame from "tns-core-modules/ui/frame"
export class Nativemediapicker extends NSObject implements UIImagePickerControllerDelegate {
public static ObjCProtocols = [UIImagePickerControllerDelegate];
get() {
let version = NSBundle.mainBundle.objectForInfoDictionaryKey("CFBundleShortVersionString");
return version;
}
static new(): Nativemediapicker {
return <Nativemediapicker>super.new();
}
private _callback: (result?) => void;
private _errorCallback: (result?) => void;
public initWithCallbackAndOptions(callback: (result?) => void, errorCallback: (result?) => void, options?): Nativemediapicker {
this._callback = callback;
this._errorCallback = errorCallback;
if (options) {
// collect options
}
console.log('initWithCallbackAndOptions')
return this;
}
static registerFileProvider(provider) { }
static pickFiles(mimeType, onResult, onError) {
onError("ERROR: For ios this feature is comming soon.");
}
static takePicture(onResult, onError) {
// if (!UIImagePickerController.isSourceTypeAvailable(UIImagePickerControllerSourceType.Camera)) {
// onError("ERROR: For ios simulator this feature is not supported.");
// return
// }
let imagePicker = UIImagePickerController.new()
imagePicker.delegate = Nativemediapicker.new().initWithCallbackAndOptions(onResult, onError, null)
imagePicker.sourceType = UIImagePickerControllerSourceType.PhotoLibrary
imagePicker.allowsEditing = false
// imagePicker.showsCameraControls = true
let topMostFrame = frame.topmost();
if (topMostFrame) {
let viewController: UIViewController = topMostFrame.currentPage && topMostFrame.currentPage.ios;
if (viewController) {
while (viewController.parentViewController) {
// find top-most view controler
viewController = viewController.parentViewController;
}
while (viewController.presentedViewController) {
// find last presented modal
viewController = viewController.presentedViewController;
}
viewController.presentViewControllerAnimatedCompletion(imagePicker, true, null);
}
}
}
static recordVideo(onResult, onError) {
onError("ERROR: For ios this feature is comming soon.");
}
static recordAudio(onResult, onError) {
onError("ERROR: For ios this feature is comming soon.");
}
imagePickerControllerDidCancel(picker): void {
console.log("imagePickerControllerDidCancel")
this._errorCallback("ERROR: Image capturing cancelled.");
}
imagePickerControllerDidFinishPickingMediaWithInfo(picker, info): void {
console.log("imagePickerControllerDidCancel")
this._errorCallback("ERROR: Image capturing done.");
}
}
I'm not getting, what I'm doing wrong and where?
Please help me, guys...
I suspect the reason is that your delegate is being cleaned up by garbage collector. One important rule with iOS is, you must always keep a reference of native object in a JS variable to keep it alive.
Try,
private _delegate;
....
this._delegate = Nativemediapicker.new().initWithCallbackAndOptions(onResult, onError, null);
imagePicker.delegate = this._delegate;
After adding this line in takePicture function it worked.
imagePicker.modalPresentationStyle = UIModalPresentationStyle.CurrentContext;
I am trying to use Ether JS in my Flutter application. I know that it is not directly supported and even the existing implementations are not really well documented.
Is there any way I can use this library in my Flutter application for Android and iOS? Any other alternative suggestion is also welcome.
I have tried js.dart but could not figure out how to use it. I am not even sure if it is the right choice for this scenario.
I have also tried Flutter WebView Plugin.
plugin.evalJavascript(
'function add(a,b){return a+b;}add(2,3);'
).then((s) {
print(s);
}
This function rightly returns 5 as the response. But I do not understand how to use the EtherJS library like this.
I am a noob with Flutter, Dart and JS. Any help will be appreciated.
I eventually solved this by using Platform channels as suggested by rmtmckenzie in this answer.
I downloaded the JS file and saved it to android/app/src/main/res/raw/ether.js and ios/runner/ether.js for Android and iOS respectively.
Installing dependencies
Android
Add LiquidCore as a dependency in app level build.gradle
implementation 'com.github.LiquidPlayer:LiquidCore:0.5.0'
iOS
For iOS I used the JavaScriptCore which is part of the SDK.
Platform Channel
In my case, I needed to create a Wallet based on a Mnemonic (look up BIP39) I pass in into the JS function. For this, I created a Platform channel which passes in the Mnemonic (which is basically of type String) as an argument and will return a JSON object when done.
Future<dynamic> getWalletFromMnemonic({#required String mnemonic}) {
return platform.invokeMethod('getWalletFromMnemonic', [mnemonic]);
}
Android Implementation (Java)
Inside MainActivity.java add this after this line
GeneratedPluginRegistrant.registerWith(this);
String CHANNEL = "UNIQUE_CHANNEL_NAME";
new MethodChannel(getFlutterView(), CHANNEL).setMethodCallHandler(
new MethodChannel.MethodCallHandler() {
#Override
public void onMethodCall(MethodCall methodCall, MethodChannel.Result result) {
if (methodCall.method.equals("getWalletFromMnemonic")) {
ArrayList<Object> args = (ArrayList<Object>) methodCall.arguments;
String mnemonic = (String) args.get(0);
JSObject walletFromMnemonic = getWalletFromMnemonic(mnemonic);
if (walletFromMnemonic == null) {
result.error("Could not create", "Wallet generation failed", null);
return;
}
String privateKey = walletFromMnemonic.property("privateKey").toString();
String address = walletFromMnemonic.property("address").toString();
HashMap<String, String> map = new HashMap<>();
map.put("privateKey", privateKey);
map.put("address", address);
JSONObject obj = new JSONObject(map);
result.success(obj.toString());
} else {
result.notImplemented();
}
}
}
);
Declare the following methods which perform the actual action of interacting with the JS library and returning the result to the platform channel.
#Nullable
#VisibleForTesting
private JSObject getWalletFromMnemonic(String mnemonic) {
JSContext jsContext = getJsContext(getEther());
JSObject wallet = getWalletObject(jsContext);
if (wallet == null) {
return null;
}
if (!wallet.hasProperty("fromMnemonic")) {
return null;
}
JSFunction walletFunction = wallet.property("fromMnemonic").toObject().toFunction();
return walletFunction.call(null, mnemonic).toObject();
}
#Nullable
#VisibleForTesting
private JSObject getWalletObject(JSContext context) {
JSObject jsEthers = context.property("ethers").toObject();
if (jsEthers.hasProperty("Wallet")) {
return jsEthers.property("Wallet").toObject();
}
return null;
}
#VisibleForTesting
String getEther() {
String s = "";
InputStream is = getResources().openRawResource(R.raw.ether);
try {
s = IOUtils.toString(is);
} catch (IOException e) {
s = null;
e.printStackTrace();
} finally {
IOUtils.closeQuietly(is);
}
return s;
}
#VisibleForTesting
JSContext getJsContext(String code) {
JSContext context = new JSContext();
context.evaluateScript(code);
return context;
}
iOS Implementation (Swift)
Add the following lines in AppDelegate.swift inside the override application method.
final let methodChannelName: String = "UNIQUE_CHANNEL_NAME"
let controller: FlutterViewController = window?.rootViewController as! FlutterViewController
let methodChannel = FlutterMethodChannel.init(name: methodChannelName, binaryMessenger: controller)
methodChannel.setMethodCallHandler({
(call: FlutterMethodCall, result: FlutterResult)-> Void in
if call.method == "getWalletFromMnemonic" {
guard let mnemonic = call.arguments as? [String] else {
return
}
if let wallet = self.getWalletFromMnemonic(mnemonic: mnemonic[0]) {
result(wallet)
} else {
result("Invalid")
}
}
})
Add the logic to interact with the JavaScriptCore.
private func getWalletFromMnemonic(mnemonic: String) -> Dictionary<String, String>? {
let PRIVATE_KEY = "privateKey"
let ADDRESS = "address"
guard let jsContext = self.initialiseJS(jsFileName: "ether") else { return nil }
guard let etherObject = jsContext.objectForKeyedSubscript("ethers") else { return nil }
guard let walletObject = etherObject.objectForKeyedSubscript("Wallet") else { return nil }
guard let walletFromMnemonicObject = walletObject.objectForKeyedSubscript("fromMnemonic") else {
return nil
}
guard let wallet = walletFromMnemonicObject.call(withArguments: [mnemonic]) else { return nil }
guard let privateKey = wallet.forProperty(PRIVATE_KEY)?.toString() else { return nil }
guard let address = wallet.forProperty(ADDRESS)?.toString() else { return nil }
var walletDictionary = Dictionary<String, String>()
walletDictionary[ADDRESS] = address
walletDictionary[PRIVATE_KEY] = privateKey
return walletDictionary
}
private func initialiseJS(jsFileName: String) -> JSContext? {
let jsContext = JSContext()
guard let jsSourcePath = Bundle.main.path(forResource: jsFileName, ofType: "js") else {
return nil
}
do {
let jsSourceContents = try String(contentsOfFile: jsSourcePath)
jsContext!.evaluateScript(jsSourceContents)
return jsContext!
} catch {
print(error.localizedDescription)
}
return nil
}
Honestly, if you're new to Flutter, Dart, and JS you are going to have some trouble with this unless you're willing to invest a fair amount of time. It does depend on what exactly you're trying to make with the Ether JS library, but in general you're going to have a hard time integrating it with flutter. There is an Ethereum package but it seems much narrower in scope than the ether.js library you've been looking at - it mostly seems focused on communication with the RPC api rather than dealing with wallets etc.
If you're dead set on using Flutter, your best bet would be to use Android & iOS specific libraries to do the actual ethereum stuff and to communicate through Platform Channels to a common api in your dart code. This could be a significant undertaking depending on how much of the API you need to expose, especially for someone new to flutter/dart and possibly to android/ios development as well. This will be much more performant than communicating back and forth with javascript running in a webview though, and realistically probably easier to code as well because flutter doesn't really have any good mechanisms for calling js code right now.
There is another option - to use a different client UI framework entirely. React native might do everything you need and has the advantage of being in Javascript so it can most likely integrate the Ether.js library easily, although I can't guarantee that it will actually fully support the ether.js library (its runtime might not have the necessary crypto extensions for example).
Future<String> loadJS(String name) async {
var givenJS = rootBundle.loadString('assets/$name.js');
return givenJS.then((String js) {
flutterWebViewPlugin.onStateChanged.listen((viewState) async {
if (viewState.type == WebViewState.finishLoad) {
flutterWebViewPlugin.evalJavascript(js);
}
});
});
}