Flutter

With AppKit Flutter, you can easily let people interact with multiple EVM compatible wallets and blockchains.

Let’s get started with the installation and configuration!

Installation

If you are just starting a new project, you can use our CLI tool to get started quickly.

1. • Add reown_appkit as dependency in your pubspec.yaml and run flutter pub get (check out the latest version)
   • Or simply run flutter pub add reown_appkit
2. • Locate your /ios/Podfile file and add the following as the first line:

platform :ios, '13.0'

3. • Run $ pod install inside /ios folder.
4. • You should now be able to run your app with flutter run --dart-define=PROJECT_ID={your_project_id}

Enable Installed Wallet Detection

To enable AppKit to detect installed wallets on the device, you need to make specific changes to the native sides of the project.

iOS

1. Open your Info.plist file.
2. Locate the <key>LSApplicationQueriesSchemes</key> section.
3. Add the desired wallet schemes as string entries within the <array>. These schemes represent the wallets you want to detect.
4. Refer to our Info.plist example file for a detailed illustration.

Example:

<key>LSApplicationQueriesSchemes</key>
<array>
  <string>metamask</string>
  <string>trust</string>
  <string>safe</string>
  <string>rainbow</string>
  <!-- Add other wallet schemes names here -->
</array>

Coinbase Wallet support

Coinbase Wallet does not use the WalletConnect protocol for communication between the dApp and the wallet.

This means that pairing topic, session topic, session events and other session-related features are not available when connecting to Coinbase Wallet.

However, you can still enable it to seamlessly connect with your dApp with these additional steps.

If you still want to support it, on your iOS and Android native side make the following changes:

iOS

1. Open your Info.plist file.
2. Locate the <key>LSApplicationQueriesSchemes</key> section.
3. Include <string>cbwallet</string> scheme as mentioned above in previous section

Example:

<key>LSApplicationQueriesSchemes</key>
<array>
  <string>cbwallet</string>
  <!-- Any other scheme previously added -->
</array>

4. Make sure pods are installed, otherwise run pod install inside your /ios folder.
5. Open your /ios/Runner.xcworkspace file with Xcode and add the following code in AppDelegate.swift file:

import CoinbaseWalletSDK

override func application(_ app: UIApplication, open url: URL, options: [UIApplication.OpenURLOptionsKey : Any] = [:]) -> Bool {
    if #available(iOS 13.0, *) {
      if (CoinbaseWalletSDK.isConfigured == true) {
        if (try? CoinbaseWalletSDK.shared.handleResponse(url)) == true {
            return true
        }
      }
    }

    return super.application(app, open: url, options: options)
}

override func application(_ application: UIApplication, continue userActivity: NSUserActivity, restorationHandler: @escaping ([UIUserActivityRestoring]?) -> Void) -> Bool {
    if #available(iOS 13.0, *) {
      if (CoinbaseWalletSDK.isConfigured == true) {
        if let url = userActivity.webpageURL,
            (try? CoinbaseWalletSDK.shared.handleResponse(url)) == true {
            return true
        }
      }
    }

    return super.application(application, continue: userActivity, restorationHandler: restorationHandler)
}

Checkout out the AppDelegate.swift file from our sample dapp for reference.

Disable Coinbase Wallet

Coinbase Wallet is enabled by default even if, in order to function properly, a few steps has to be done as described in the previous section. However, if you don’t want to include/support Coinbase Wallet on your app you just need to pass Coinbase Wallet id fd20dc426fb37566d803205b19bbc1d4096b248ac04548e3cfb6b3a38bd033aa to excludedWalletIds options Array.

Phantom Wallet support

Phantom Wallet support is available from reown_appkit: ^1.4.0.

Phantom Wallet does not use the WalletConnect protocol for communication between the dApp and the wallet, instead it provides an internal API mechanism based on deep/universal links.

This means that pairing topic, session topic, session events and other session-related features are not available when connecting to Phantom Wallet and the interaction is really basic. Dapp sends a request, Phantom Wallet responds. That’s all.

Furthermore, Phantom Wallet’s deep/universal linking mechanism supports interaction exclusively with the Solana network. This means that if you have EVM networks configured in your AppKit instance, they will not be available for use after connecting with Phantom.

In order to support Phantom Wallet interactions a few extra steps has to be performed (only if you haven’t implemented Link Mode already).

1. First, be sure you already have your redirection back property configure in your dApp’s metadata. See Redirect to your dApp
2. Then you will have to implement your own Deep Link mechanism on Flutter (and native) side so when a link is received through it, you would just call await _appKitModal.dispatchEnvelope(link);

As a guidance, here you can see how it’s done in our sample dApp:

First, on Flutter side we create an EventChannel where links are going to be received and passed to dispatchEnvelope().

Flutter

import 'package:flutter/foundation.dart';
import 'package:flutter/services.dart';
import 'package:reown_appkit/modal/i_appkit_modal_impl.dart';

class DeepLinkHandler {
  static const _eventChannel = EventChannel('com.exampledapp/events');
  static late IReownAppKitModal _appKitModal;

  static void init(IReownAppKitModal appKitModal) {
    if (kIsWeb) return;

    try {
      _appKitModal = appKitModal;
      _eventChannel.receiveBroadcastStream().listen(_onLink, onError: _onError);
    } catch (e) {
      debugPrint('[SampleDapp] checkInitialLink $e');
    }
  }

  static void _onLink(dynamic link) async {
    try {
      _appKitModal.dispatchEnvelope(link);
    } catch (e) {
      print(e);
    }
  }

  static void _onError(dynamic error) {
    print(error);
  }
}

Then, on both native sides we leverage native APIs to capture the app opening link and send it to Flutter side.

iOS

import Flutter
import UIKit

@main
@objc class AppDelegate: FlutterAppDelegate {
  private static let EVENTS_CHANNEL = "com.exampledapp/events"
  private var eventsChannel: FlutterEventChannel?
  private let linkStreamHandler = LinkStreamHandler()

  override func application(_ application: UIApplication, didFinishLaunchingWithOptions launchOptions: [UIApplication.LaunchOptionsKey: Any]?) -> Bool {
    GeneratedPluginRegistrant.register(with: self)

    let controller = window.rootViewController as! FlutterViewController
    eventsChannel = FlutterEventChannel(name: AppDelegate.EVENTS_CHANNEL, binaryMessenger: controller.binaryMessenger)
    eventsChannel?.setStreamHandler(linkStreamHandler)

    if let userActivityDictionary = launchOptions?[.userActivityDictionary] as? [String: Any],
      let userActivity = userActivityDictionary["UIApplicationLaunchOptionsUserActivityKey"] as? NSUserActivity,
      userActivity.activityType == NSUserActivityTypeBrowsingWeb {

      handleIncomingUniversalLink(userActivity: userActivity)
    }

    return super.application(application, didFinishLaunchingWithOptions: launchOptions)
  }

  override func application(_ app: UIApplication, open url: URL, options: [UIApplication.OpenURLOptionsKey : Any] = [:]) -> Bool {
    return linkStreamHandler.handleLink(url.absoluteString)
  }

  override func application(_ application: UIApplication, continue userActivity: NSUserActivity, restorationHandler: @escaping ([UIUserActivityRestoring]?) -> Void) -> Bool {
    if userActivity.activityType == NSUserActivityTypeBrowsingWeb {
      handleIncomingUniversalLink(userActivity: userActivity)
      return true
    }

    return false
  }

  private func handleIncomingUniversalLink(userActivity: NSUserActivity) {
    if let url = userActivity.webpageURL {
      print("App launched with Universal Link: \(url.absoluteString)")
      let _ = linkStreamHandler.handleLink(url.absoluteString)
    }
  }
}

class LinkStreamHandler: NSObject, FlutterStreamHandler {
  var eventSink: FlutterEventSink?
  var queuedLinks = [String]()

  func onListen(withArguments arguments: Any?, eventSink events: @escaping FlutterEventSink) -> FlutterError? {
    self.eventSink = events
    queuedLinks.forEach({ events($0) })
    queuedLinks.removeAll()
    return nil
  }

  func onCancel(withArguments arguments: Any?) -> FlutterError? {
    self.eventSink = nil
    return nil
  }

  func handleLink(_ link: String) -> Bool {
    guard let eventSink = eventSink else {
      queuedLinks.append(link)
      return false
    }
    eventSink(link)
    return true
  }
}

Links to full examples:

• Android’s platform specific code (only eventsChannel is important Phantom wise)
• iOS’s platform specific code (only eventsChannel is important Phantom wise)
• Dart’s specific code (only eventsChannel is important Phantom wise)

Constructing a Solana transaction would depend on the library/package of your choice but in our sample dApp’s code you can see how we do it using solana_web3 package.

Disable Phantom Wallet

Phantom Wallet is enabled by default even if, in order to function properly, a few steps has to be done as described in the previous section. However, if you don’t want to include/support Phantom Wallet on your app you just need to pass Phantom Wallet id a797aa35c0fadbfc1a53e7f675162ed5226968b44a19ee3d24385c64d1d3c393 to excludedWalletIds options Array.

Example

AppKit with Flutter example

Check the Flutter example

Test Apps

Want to see AppKit in action? Download our sample AppKit apps below and explore what it can do. Enjoy! 😊

• Android Build (Firebase)
• iOS Build (Testflight)