adding in initial plugin code

lib/multimedia.dart

@@ -0,0 +1,8 @@
+
+import 'multimedia_platform_interface.dart';
+
+class Multimedia {
+  Future<String?> getPlatformVersion() {
+    return MultimediaPlatform.instance.getPlatformVersion();
+  }
+}

lib/multimedia_method_channel.dart

@@ -0,0 +1,17 @@
+import 'package:flutter/foundation.dart';
+import 'package:flutter/services.dart';
+
+import 'multimedia_platform_interface.dart';
+
+/// An implementation of [MultimediaPlatform] that uses method channels.
+class MethodChannelMultimedia extends MultimediaPlatform {
+  /// The method channel used to interact with the native platform.
+  @visibleForTesting
+  final methodChannel = const MethodChannel('multimedia');
+
+  @override
+  Future<String?> getPlatformVersion() async {
+    final version = await methodChannel.invokeMethod<String>('getPlatformVersion');
+    return version;
+  }
+}

lib/multimedia_platform_interface.dart

@@ -0,0 +1,29 @@
+import 'package:plugin_platform_interface/plugin_platform_interface.dart';
+
+import 'multimedia_method_channel.dart';
+
+abstract class MultimediaPlatform extends PlatformInterface {
+  /// Constructs a MultimediaPlatform.
+  MultimediaPlatform() : super(token: _token);
+
+  static final Object _token = Object();
+
+  static MultimediaPlatform _instance = MethodChannelMultimedia();
+
+  /// The default instance of [MultimediaPlatform] to use.
+  ///
+  /// Defaults to [MethodChannelMultimedia].
+  static MultimediaPlatform get instance => _instance;
+
+  /// Platform-specific implementations should set this with their own
+  /// platform-specific class that extends [MultimediaPlatform] when
+  /// they register themselves.
+  static set instance(MultimediaPlatform instance) {
+    PlatformInterface.verifyToken(instance, _token);
+    _instance = instance;
+  }
+
+  Future<String?> getPlatformVersion() {
+    throw UnimplementedError('platformVersion() has not been implemented.');
+  }
+}