Flutter Cast Framework

Overview

Flutter Cast Framework is a POC of a flutter plugin that lets you use Chromecast API in a flutter app.

Exposed APIs

Currently only the following APIs are integrated (both Android and iOS):

• Cast State
• Session state
• Send custom message
• Listen to received custom messages
• Cast Button
• Chromecast connection

Setup

Add Dependency

Clone this repo and add the following piece of code to your app's pubspec

dependencies:
  flutter_cast_framework:
    path: ../flutter_cast_framework/ # the path depends on where you cloned this repo

Android Setup

1. Create CastOptionsProvider

Add the following class to your Android project:

import android.content.Context
import com.google.android.gms.cast.framework.CastOptions
import com.google.android.gms.cast.framework.OptionsProvider
import com.google.android.gms.cast.framework.SessionProvider

class CastOptionsProvider : OptionsProvider {
    override fun getCastOptions(context: Context): CastOptions {
        return CastOptions.Builder()
                .setReceiverApplicationId("4F8B3483") // Your receiver Application ID
                .build()
    }

    override fun getAdditionalSessionProviders(context: Context): List<SessionProvider>? {
        return null
    }
}

2. Load CastOptionsProvider

Add the following entry in the AndroidManifest.xml file under the <application> tag to reference the CastOptionsProvider class:

<application>
    <meta-data
        android:name="com.google.android.gms.cast.framework.OPTIONS_PROVIDER_CLASS_NAME"
        android:value="com.gianlucaparadise.flutter_cast_framework_example.CastOptionsProvider" />
</application>

3. Theme

Make sure that your application and your activity are using an AppCompat theme (as stated here).

iOS Setup

1. Minimum iOS version

Make sure you minimum iOS version is 10.0. Select Runner from left pane > General tab > Deployment Info > Target: set 10.0 or higher

2. Install iOS dependencies

When Xcode is closed, open a terminal at the root folder of your project and run:

cd ios && pod install

3. Open project in Xcode

To open your flutter project with Xcode, from root folder run open ios/Runner.xcworkspace

4. Chromecast SDK setup

Add the following lines to your AppDelegate.swift:

 import UIKit
 import Flutter
+import GoogleCast
 
 @UIApplicationMain
-@objc class AppDelegate: FlutterAppDelegate {
+@objc class AppDelegate: FlutterAppDelegate, GCKLoggerDelegate {
+  let kReceiverAppID = "4F8B3483" // Your receiver Application ID
+  let kDebugLoggingEnabled = true
+  
   override func application(
     _ application: UIApplication,
     didFinishLaunchingWithOptions launchOptions: [UIApplicationLaunchOptionsKey: Any]?
   ) -> Bool {
+    let criteria = GCKDiscoveryCriteria(applicationID: kReceiverAppID)
+    let options = GCKCastOptions(discoveryCriteria: criteria)
+    GCKCastContext.setSharedInstanceWith(options)
+
+    // Enable logger.
+    GCKLogger.sharedInstance().delegate = self
+    
     GeneratedPluginRegistrant.register(with: self)
     return super.application(application, didFinishLaunchingWithOptions: launchOptions)
   }
+  
+  // MARK: - GCKLoggerDelegate
+  
+  func logMessage(_ message: String,
+                  at level: GCKLoggerLevel,
+                  fromFunction function: String,
+                  location: String) {
+      if (kDebugLoggingEnabled) {
+          print(function + " - " + message)
+      }
+  }
 }

Tech notes

I used this project to test the capabilities of the following technologies:

• Chromecast API (Sender - Android SDK)
• Flutter
• Flutter custom platform-specific code