DashboardFragment.kt

/**
 * [DashboardFragment] is a custom flutter fragment which is used to pass custom
 * data from native app to dashboard part in flutter. This communication is set up on
 * both native and in flutter module.
 *
 * @see To refer to the flutter part, please refer the flutter module.
 * */

const val KeyData = "key_data"
const val CommunicationChannel = "com.app/dataShare"

class DashboardFragment: FlutterFragment() {

    private val dashboardRoute = "/loan_dashboard"
    private val callbackMethod = "shareData"

    var data: String? = null

    companion object {
        fun instance(data: String): DashboardFragment {
            val fragment = DashboardFragment()
            val bundle = Bundle().apply {
                putString(KeyData,data)
            }
            fragment.arguments = bundle
            return fragment
        }
    }

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        arguments?.let {args ->
            if (args.containsKey(KeyData)) {
                data = args.getString(KeyData)
            }
        }
    }

    override fun provideFlutterEngine(context: Context): FlutterEngine? {
        val engine = FlutterEngine(requireActivity())
        engine.navigationChannel.setInitialRoute(dashboardRoute)
        return engine
    }

    override fun configureFlutterEngine(flutterEngine: FlutterEngine) {
        super.configureFlutterEngine(flutterEngine)
        GeneratedPluginRegistrant.registerWith(flutterEngine);
        MethodChannel(flutterEngine.dartExecutor.binaryMessenger, CommunicationChannel).setMethodCallHandler {
            call, result ->
            if (call.method == callbackMethod) {
              data?.let { 
                result.success(it)
              } ?: result.error("error")
            } else {
              result.notImplemented()
            }
        }
    }
}