diff --git a/android/src/main/java/io/agora/agorartcengine/AgoraRtcEnginePlugin.java b/android/src/main/java/io/agora/agorartcengine/AgoraRtcEnginePlugin.java
index 3f5385d92..c8d1d580f 100644
--- a/android/src/main/java/io/agora/agorartcengine/AgoraRtcEnginePlugin.java
+++ b/android/src/main/java/io/agora/agorartcengine/AgoraRtcEnginePlugin.java
@@ -1,11 +1,5 @@
 package io.agora.agorartcengine;
 
-import io.flutter.plugin.common.MethodCall;
-import io.flutter.plugin.common.MethodChannel;
-import io.flutter.plugin.common.MethodChannel.MethodCallHandler;
-import io.flutter.plugin.common.MethodChannel.Result;
-import io.flutter.plugin.common.PluginRegistry.Registrar;
-
 import android.content.Context;
 import android.graphics.Rect;
 import android.os.Handler;
@@ -14,966 +8,1021 @@
 
 import java.util.ArrayList;
 import java.util.HashMap;
-import java.util.Map;
-import java.util.Objects;
 
-import io.agora.rtc.RtcEngine;
 import io.agora.rtc.IRtcEngineEventHandler;
+import io.agora.rtc.RtcEngine;
+import io.agora.rtc.video.BeautyOptions;
 import io.agora.rtc.video.VideoCanvas;
 import io.agora.rtc.video.VideoEncoderConfiguration;
-import io.agora.rtc.video.BeautyOptions;
-
+import io.flutter.plugin.common.MethodCall;
+import io.flutter.plugin.common.MethodChannel;
+import io.flutter.plugin.common.MethodChannel.MethodCallHandler;
+import io.flutter.plugin.common.MethodChannel.Result;
+import io.flutter.plugin.common.PluginRegistry.Registrar;
 import io.flutter.plugin.common.StandardMessageCodec;
 
-/** AgoraRtcEnginePlugin */
+/**
+ * AgoraRtcEnginePlugin
+ */
 public class AgoraRtcEnginePlugin implements MethodCallHandler {
 
-  private final Registrar mRegistrar;
-  private final MethodChannel mMethodChannel;
-  private RtcEngine mRtcEngine;
-  private HashMap<String, SurfaceView> mRendererViews;
-  private Handler mEventHandler = new Handler(Looper.getMainLooper());
-
-  void addView(SurfaceView view, int id) {
-    mRendererViews.put("" + id, view);
-  }
-
-  private void removeView(int id) {
-    mRendererViews.remove("" + id);
-  }
-
-  private SurfaceView getView(int id) {
-    return mRendererViews.get("" + id);
-  }
-
-  /** Plugin registration. */
-  public static void registerWith(Registrar registrar) {
-    final MethodChannel channel = new MethodChannel(registrar.messenger(), "agora_rtc_engine");
-
-    AgoraRtcEnginePlugin plugin = new AgoraRtcEnginePlugin(registrar, channel);
-    channel.setMethodCallHandler(plugin);
-
-    AgoraRenderViewFactory fac = new AgoraRenderViewFactory(StandardMessageCodec.INSTANCE, plugin);
-    registrar.platformViewRegistry().registerViewFactory("AgoraRendererView", fac);
-  }
-
-  private AgoraRtcEnginePlugin(Registrar registrar, MethodChannel channel) {
-    this.mRegistrar = registrar;
-    this.mMethodChannel = channel;
-    this.mRendererViews = new HashMap<>();
-  }
-
-  private Context getActiveContext() {
-    return (mRegistrar.activity() != null) ? mRegistrar.activity() : mRegistrar.context();
-  }
-
-  @Override
-  public void onMethodCall(MethodCall call, Result rawResult) {
-    Context context = getActiveContext();
-    MethodChannel.Result result = new MethodResultWrapper(rawResult, mEventHandler);
-
-    switch (call.method) {
-      // Core Methods
-      case "create": {
-        try {
-          String appId = call.argument("appId");
-          mRtcEngine = RtcEngine.create(context, appId, mRtcEventHandler);
-        } catch (Exception e) {
-          throw new RuntimeException("NEED TO check rtc sdk init fatal error\n");
-        }
-      }
-      break;
-      case "destroy": {
-        RtcEngine.destroy();
-      }
-      break;
-      case "setChannelProfile": {
-        int profile = call.argument("profile");
-        mRtcEngine.setChannelProfile(profile);
-      }
-      break;
-      case "setClientRole": {
-        int role = call.argument("role");
-        mRtcEngine.setClientRole(role);
-      }
-      break;
-      case "joinChannel": {
-        String token = call.argument("token");
-        String channel = call.argument("channelId");
-        String info = call.argument("info");
-        int uid = call.argument("uid");
-        mRtcEngine.joinChannel(token, channel, info, uid);
-      }
-      break;
-      case "leaveChannel": {
-        mRtcEngine.leaveChannel();
-      }
-      break;
-      case "renewToken": {
-        String token = call.argument("token");
-        mRtcEngine.renewToken(token);
-      }
-      break;
-      case "enableWebSdkInteroperability": {
-        boolean enabled = call.argument("enabled");
-        mRtcEngine.enableWebSdkInteroperability(enabled);
-      }
-      break;
-      case "getConnectionState": {
-        int state = mRtcEngine.getConnectionState();
-        result.success(state);
-      }
-      break;
-      // Core Audio
-      case "enableAudio": {
-        mRtcEngine.enableAudio();
-      }
-      break;
-      case "disableAudio": {
-        mRtcEngine.disableAudio();
-      }
-      break;
-      case "setAudioProfile": {
-        int profile = call.argument("profile");
-        int scenario = call.argument("scenario");
-        mRtcEngine.setAudioProfile(profile, scenario);
-      }
-      break;
-      case "adjustRecordingSignalVolume": {
-        int volume = call.argument("volume");
-        mRtcEngine.adjustRecordingSignalVolume(volume);
-      }
-      break;
-      case "adjustPlaybackSignalVolume": {
-        int volume = call.argument("volume");
-        mRtcEngine.adjustPlaybackSignalVolume(volume);
-      }
-      break;
-      case "enableAudioVolumeIndication": {
-        int interval = call.argument("interval");
-        int smooth = call.argument("smooth");
-        mRtcEngine.enableAudioVolumeIndication(interval, smooth);
-      }
-      break;
-      case "enableLocalAudio": {
-        boolean enabled = call.argument("enabled");
-        mRtcEngine.enableLocalAudio(enabled);
-      }
-      break;
-      case "muteLocalAudioStream": {
-        boolean muted = call.argument("muted");
-        mRtcEngine.muteLocalAudioStream(muted);
-      }
-      break;
-      case "muteRemoteAudioStream": {
-        int uid = call.argument("uid");
-        boolean muted = call.argument("muted");
-        mRtcEngine.muteRemoteAudioStream(uid, muted);
-      }
-      break;
-      case "muteAllRemoteAudioStreams": {
-        boolean muted = call.argument("muted");
-        mRtcEngine.muteAllRemoteAudioStreams(muted);
-      }
-      break;
-      case "setDefaultMuteAllRemoteAudioStreams": {
-        boolean muted = call.argument("muted");
-        mRtcEngine.setDefaultMuteAllRemoteAudioStreams(muted);
-      }
-      break;
-      // Video Pre-process and Post-process
-      case "setBeautyEffectOptions": {
-        boolean enabled = call.argument("enabled");
-        HashMap<String, Object> optionsMap = call.argument("options");
-        BeautyOptions options = beautyOptionsFromMap(optionsMap);
-        mRtcEngine.setBeautyEffectOptions(enabled, options);
-      }
-      break;
-      // Core Video
-      case "enableVideo": {
-        mRtcEngine.enableVideo();
-      }
-      break;
-      case "disableVideo": {
-        mRtcEngine.disableVideo();
-      }
-      break;
-      case "setVideoEncoderConfiguration": {
-        HashMap<String, Object> configDic = call.argument("config");
-        VideoEncoderConfiguration config = videoEncoderConfigurationFromMap(configDic);
-        mRtcEngine.setVideoEncoderConfiguration(config);
-      }
-      break;
-      case "removeNativeView": {
-        int viewId = call.argument("viewId");
-        removeView(viewId);
-      }
-      break;
-      case "setupLocalVideo": {
-        int localViewId = call.argument("viewId");
-        SurfaceView localView = getView(localViewId);
-        int localRenderMode = call.argument("renderMode");
-        VideoCanvas localCanvas = new VideoCanvas(localView);
-        localCanvas.renderMode = localRenderMode;
-        mRtcEngine.setupLocalVideo(localCanvas);
-      }
-      break;
-      case "setupRemoteVideo": {
-        int remoteViewId = call.argument("viewId");
-        SurfaceView view = getView(remoteViewId);
-        int remoteRenderMode = call.argument("renderMode");
-        int remoteUid = call.argument("uid");
-        mRtcEngine.setupRemoteVideo(new VideoCanvas(view, remoteRenderMode, remoteUid));
-      }
-      break;
-      case "setLocalRenderMode": {
-        int mode = call.argument("mode");
-        mRtcEngine.setLocalRenderMode(mode);
-      }
-      break;
-      case "setRemoteRenderMode": {
-        int uid = call.argument("uid");
-        int mode = call.argument("mode");
-        mRtcEngine.setRemoteRenderMode(uid, mode);
-      }
-      break;
-      case "startPreview": {
-        mRtcEngine.startPreview();
-      }
-      break;
-      case "stopPreview": {
-        mRtcEngine.stopPreview();
-      }
-      break;
-      case "enableLocalVideo": {
-        boolean enabled = call.argument("enabled");
-        mRtcEngine.enableLocalVideo(enabled);
-      }
-      break;
-      case "muteLocalVideoStream": {
-        boolean muted = call.argument("muted");
-        mRtcEngine.muteLocalVideoStream(muted);
-      }
-      break;
-      case "muteRemoteVideoStream": {
-        int uid = call.argument("uid");
-        boolean muted = call.argument("muted");
-        mRtcEngine.muteRemoteVideoStream(uid, muted);
-      }
-      break;
-      case "muteAllRemoteVideoStreams": {
-        boolean muted = call.argument("muted");
-        mRtcEngine.muteAllRemoteVideoStreams(muted);
-      }
-      break;
-      case "setDefaultMuteAllRemoteVideoStreams": {
-        boolean muted = call.argument("muted");
-        mRtcEngine.setDefaultMuteAllRemoteVideoStreams(muted);
-      }
-      break;
-
-      // Audio Routing Controller
-      case "setDefaultAudioRouteToSpeaker": {
-        boolean defaultToSpeaker = call.argument("defaultToSpeaker");
-        mRtcEngine.setDefaultAudioRoutetoSpeakerphone(defaultToSpeaker);
-      }
-      break;
-      case "setEnableSpeakerphone": {
-        boolean enabled = call.argument("enabled");
-        mRtcEngine.setEnableSpeakerphone(enabled);
-      }
-      break;
-      case "isSpeakerphoneEnabled": {
-        boolean enabled = mRtcEngine.isSpeakerphoneEnabled();
-        result.success(enabled);
-      }
-      break;
-
-      // Stream Fallback
-      case "setRemoteUserPriority": {
-        int uid = call.argument("uid");
-        int userPriority = call.argument("userPriority");
-        mRtcEngine.setRemoteUserPriority(uid, userPriority);
-      }
-      case "setLocalPublishFallbackOption": {
-        int option = call.argument("option");
-        mRtcEngine.setLocalPublishFallbackOption(option);
-      }
-      break;
-      case "setRemoteSubscribeFallbackOption": {
-        int option = call.argument("option");
-        mRtcEngine.setRemoteSubscribeFallbackOption(option);
-      }
-      break;
-
-      // Dual-stream Mode
-      case "enableDualStreamMode": {
-        boolean enabled = call.argument("enabled");
-        mRtcEngine.enableDualStreamMode(enabled);
-      }
-      break;
-      case "setRemoteVideoStreamType": {
-        int uid = call.argument("uid");
-        int streamType = call.argument("streamType");
-        mRtcEngine.setRemoteVideoStreamType(uid, streamType);
-      }
-      break;
-      case "setRemoteDefaultVideoStreamType": {
-        int streamType = call.argument("streamType");
-        mRtcEngine.setRemoteDefaultVideoStreamType(streamType);
-      }
-      break;
-
-      // Encryption
-      case "setEncryptionSecret": {
-        String secret = call.argument("secret");
-        mRtcEngine.setEncryptionSecret(secret);
-      }
-      break;
-      case "setEncryptionMode": {
-        String encryptionMode = call.argument("encryptionMode");
-        mRtcEngine.setEncryptionMode(encryptionMode);
-      }
-      break;
-
-      // Camera Control
-      case "switchCamera": {
-        mRtcEngine.switchCamera();
-      }
-      break;
-
-      // Miscellaneous Methods
-      case "getSdkVersion": {
-        String version = RtcEngine.getSdkVersion();
-        result.success(version);
-      }
-      break;
-
-      default:
-        result.notImplemented();
-    }
-  }
-
-  private VideoEncoderConfiguration.ORIENTATION_MODE orientationFromValue(int value) {
-    switch (value) {
-      case 0:
-        return VideoEncoderConfiguration.ORIENTATION_MODE.ORIENTATION_MODE_ADAPTIVE;
-      case 1:
-        return VideoEncoderConfiguration.ORIENTATION_MODE.ORIENTATION_MODE_FIXED_LANDSCAPE;
-      case 2:
-        return VideoEncoderConfiguration.ORIENTATION_MODE.ORIENTATION_MODE_FIXED_PORTRAIT;
-      default:
-        return VideoEncoderConfiguration.ORIENTATION_MODE.ORIENTATION_MODE_ADAPTIVE;
-    }
-  }
+    private final Registrar mRegistrar;
+    private final MethodChannel mMethodChannel;
+    private RtcEngine mRtcEngine;
+    private HashMap<String, SurfaceView> mRendererViews;
+    private Handler mEventHandler = new Handler(Looper.getMainLooper());
 
-  private final IRtcEngineEventHandler mRtcEventHandler = new IRtcEngineEventHandler() {
-    @Override
-    public void onWarning(int warn) {
-      super.onWarning(warn);
-      HashMap<String, Object> map = new HashMap<>();
-      map.put("warn", warn);
-      invokeMethod("onWarning", map);
+    void addView(SurfaceView view , int id) {
+        mRendererViews.put("" + id , view);
     }
 
-    @Override
-    public void onError(int err) {
-      super.onError(err);
-      HashMap<String, Object> map = new HashMap<>();
-      map.put("err", err);
-      invokeMethod("onError", map);
+    private void removeView(int id) {
+        mRendererViews.remove("" + id);
     }
 
-    @Override
-    public void onJoinChannelSuccess(String channel, int uid, int elapsed) {
-      super.onJoinChannelSuccess(channel, uid, elapsed);
-      HashMap<String, Object> map = new HashMap<>();
-      map.put("channel", channel);
-      map.put("uid", uid);
-      map.put("elapsed", elapsed);
-      invokeMethod("onJoinChannelSuccess", map);
+    private SurfaceView getView(int id) {
+        return mRendererViews.get("" + id);
     }
 
-    @Override
-    public void onRejoinChannelSuccess(String channel, int uid, int elapsed) {
-      super.onRejoinChannelSuccess(channel, uid, elapsed);
-      HashMap<String, Object> map = new HashMap<>();
-      map.put("channel", channel);
-      map.put("uid", uid);
-      map.put("elapsed", elapsed);
-      invokeMethod("onRejoinChannelSuccess", map);
-    }
+    /**
+     * Plugin registration.
+     */
+    public static void registerWith(Registrar registrar) {
+        final MethodChannel channel = new MethodChannel(registrar.messenger() , "agora_rtc_engine");
 
-    @Override
-    public void onLeaveChannel(RtcStats stats) {
-      super.onLeaveChannel(stats);
-      HashMap<String, Object> map = new HashMap<>();
-      map.put("stats", mapFromStats(stats));
-      invokeMethod("onLeaveChannel", map);
-    }
+        AgoraRtcEnginePlugin plugin = new AgoraRtcEnginePlugin(registrar , channel);
+        channel.setMethodCallHandler(plugin);
 
-    @Override
-    public void onClientRoleChanged(int oldRole, int newRole) {
-      super.onClientRoleChanged(oldRole, newRole);
-      HashMap<String, Object> map = new HashMap<>();
-      map.put("oldRole", oldRole);
-      map.put("newRole", newRole);
-      invokeMethod("onClientRoleChanged", map);
+        AgoraRenderViewFactory fac = new AgoraRenderViewFactory(StandardMessageCodec.INSTANCE ,
+                plugin);
+        registrar.platformViewRegistry().registerViewFactory("AgoraRendererView" , fac);
     }
 
-    @Override
-    public void onUserJoined(int uid, int elapsed) {
-      super.onUserJoined(uid, elapsed);
-      HashMap<String, Object> map = new HashMap<>();
-      map.put("uid", uid);
-      map.put("elapsed", elapsed);
-      invokeMethod("onUserJoined", map);
+    private AgoraRtcEnginePlugin(Registrar registrar , MethodChannel channel) {
+        this.mRegistrar = registrar;
+        this.mMethodChannel = channel;
+        this.mRendererViews = new HashMap<>();
     }
 
-    @Override
-    public void onUserOffline(int uid, int reason) {
-      super.onUserOffline(uid, reason);
-      HashMap<String, Object> map = new HashMap<>();
-      map.put("uid", uid);
-      map.put("reason", reason);
-      invokeMethod("onUserOffline", map);
+    private Context getActiveContext() {
+        return (mRegistrar.activity() != null) ? mRegistrar.activity() : mRegistrar.context();
     }
 
     @Override
-    public void onConnectionStateChanged(int state, int reason) {
-      super.onConnectionStateChanged(state, reason);
-      HashMap<String, Object> map = new HashMap<>();
-      map.put("state", state);
-      map.put("reason", reason);
-      invokeMethod("onConnectionStateChanged", map);
+    public void onMethodCall(MethodCall call , Result result) {
+        Context context = getActiveContext();
+        // MethodChannel.Result result = new MethodResultWrapper(rawResult, mEventHandler);
+        // 本方法执行在主线程，result调用没有跨线程，无需再次发送
+
+        switch (call.method) {
+            // Core Methods
+            case "create": {
+                try {
+                    String appId = call.argument("appId");
+                    mRtcEngine = RtcEngine.create(context , appId , mRtcEventHandler);
+                    result.success(null);
+                } catch (Exception e) {
+                    throw new RuntimeException("NEED TO check rtc sdk init fatal error\n");
+                }
+            }
+            break;
+            case "destroy": {
+                RtcEngine.destroy();
+                result.success(null);
+            }
+            break;
+            case "setChannelProfile": {
+                int profile = call.argument("profile");
+                mRtcEngine.setChannelProfile(profile);
+                result.success(null);
+            }
+            break;
+            case "setClientRole": {
+                int role = call.argument("role");
+                mRtcEngine.setClientRole(role);
+                result.success(null);
+            }
+            break;
+            case "joinChannel": {
+                String token = call.argument("token");
+                String channel = call.argument("channelId");
+                String info = call.argument("info");
+                int uid = call.argument("uid");
+                result.success(mRtcEngine.joinChannel(token , channel , info , uid) >= 0);
+            }
+            break;
+            case "leaveChannel": {
+                result.success(mRtcEngine.leaveChannel() >= 0);
+            }
+            break;
+            case "renewToken": {
+                String token = call.argument("token");
+                mRtcEngine.renewToken(token);
+                result.success(null);
+            }
+            break;
+            case "enableWebSdkInteroperability": {
+                boolean enabled = call.argument("enabled");
+                mRtcEngine.enableWebSdkInteroperability(enabled);
+                result.success(null);
+            }
+            break;
+            case "getConnectionState": {
+                int state = mRtcEngine.getConnectionState();
+                result.success(state);
+            }
+            break;
+            // Core Audio
+            case "enableAudio": {
+                mRtcEngine.enableAudio();
+                result.success(null);
+            }
+            break;
+            case "disableAudio": {
+                mRtcEngine.disableAudio();
+                result.success(null);
+            }
+            break;
+            case "setAudioProfile": {
+                int profile = call.argument("profile");
+                int scenario = call.argument("scenario");
+                mRtcEngine.setAudioProfile(profile , scenario);
+                result.success(null);
+            }
+            break;
+            case "adjustRecordingSignalVolume": {
+                int volume = call.argument("volume");
+                mRtcEngine.adjustRecordingSignalVolume(volume);
+                result.success(null);
+            }
+            break;
+            case "adjustPlaybackSignalVolume": {
+                int volume = call.argument("volume");
+                mRtcEngine.adjustPlaybackSignalVolume(volume);
+                result.success(null);
+            }
+            break;
+            case "enableAudioVolumeIndication": {
+                int interval = call.argument("interval");
+                int smooth = call.argument("smooth");
+                mRtcEngine.enableAudioVolumeIndication(interval , smooth);
+                result.success(null);
+            }
+            break;
+            case "enableLocalAudio": {
+                boolean enabled = call.argument("enabled");
+                mRtcEngine.enableLocalAudio(enabled);
+                result.success(null);
+            }
+            break;
+            case "muteLocalAudioStream": {
+                boolean muted = call.argument("muted");
+                mRtcEngine.muteLocalAudioStream(muted);
+                result.success(null);
+            }
+            break;
+            case "muteRemoteAudioStream": {
+                int uid = call.argument("uid");
+                boolean muted = call.argument("muted");
+                mRtcEngine.muteRemoteAudioStream(uid , muted);
+                result.success(null);
+            }
+            break;
+            case "muteAllRemoteAudioStreams": {
+                boolean muted = call.argument("muted");
+                mRtcEngine.muteAllRemoteAudioStreams(muted);
+                result.success(null);
+            }
+            break;
+            case "setDefaultMuteAllRemoteAudioStreams": {
+                boolean muted = call.argument("muted");
+                mRtcEngine.setDefaultMuteAllRemoteAudioStreams(muted);
+                result.success(null);
+            }
+            break;
+            // Video Pre-process and Post-process
+            case "setBeautyEffectOptions": {
+                boolean enabled = call.argument("enabled");
+                HashMap<String, Object> optionsMap = call.argument("options");
+                BeautyOptions options = beautyOptionsFromMap(optionsMap);
+                mRtcEngine.setBeautyEffectOptions(enabled , options);
+                result.success(null);
+            }
+            break;
+            // Core Video
+            case "enableVideo": {
+                mRtcEngine.enableVideo();
+                result.success(null);
+            }
+            break;
+            case "disableVideo": {
+                mRtcEngine.disableVideo();
+                result.success(null);
+            }
+            break;
+            case "setVideoEncoderConfiguration": {
+                HashMap<String, Object> configDic = call.argument("config");
+                VideoEncoderConfiguration config = videoEncoderConfigurationFromMap(configDic);
+                mRtcEngine.setVideoEncoderConfiguration(config);
+                result.success(null);
+            }
+            break;
+            case "removeNativeView": {
+                int viewId = call.argument("viewId");
+                removeView(viewId);
+                result.success(null);
+            }
+            break;
+            case "setupLocalVideo": {
+                int localViewId = call.argument("viewId");
+                SurfaceView localView = getView(localViewId);
+                int localRenderMode = call.argument("renderMode");
+                VideoCanvas localCanvas = new VideoCanvas(localView);
+                localCanvas.renderMode = localRenderMode;
+                mRtcEngine.setupLocalVideo(localCanvas);
+                result.success(null);
+            }
+            break;
+            case "setupRemoteVideo": {
+                int remoteViewId = call.argument("viewId");
+                SurfaceView view = getView(remoteViewId);
+                int remoteRenderMode = call.argument("renderMode");
+                int remoteUid = call.argument("uid");
+                mRtcEngine.setupRemoteVideo(new VideoCanvas(view , remoteRenderMode , remoteUid));
+                result.success(null);
+            }
+            break;
+            case "setLocalRenderMode": {
+                int mode = call.argument("mode");
+                mRtcEngine.setLocalRenderMode(mode);
+                result.success(null);
+            }
+            break;
+            case "setRemoteRenderMode": {
+                int uid = call.argument("uid");
+                int mode = call.argument("mode");
+                mRtcEngine.setRemoteRenderMode(uid , mode);
+                result.success(null);
+            }
+            break;
+            case "startPreview": {
+                mRtcEngine.startPreview();
+                result.success(null);
+            }
+            break;
+            case "stopPreview": {
+                mRtcEngine.stopPreview();
+                result.success(null);
+            }
+            break;
+            case "enableLocalVideo": {
+                boolean enabled = call.argument("enabled");
+                mRtcEngine.enableLocalVideo(enabled);
+                result.success(null);
+            }
+            break;
+            case "muteLocalVideoStream": {
+                boolean muted = call.argument("muted");
+                mRtcEngine.muteLocalVideoStream(muted);
+                result.success(null);
+            }
+            break;
+            case "muteRemoteVideoStream": {
+                int uid = call.argument("uid");
+                boolean muted = call.argument("muted");
+                mRtcEngine.muteRemoteVideoStream(uid , muted);
+                result.success(null);
+            }
+            break;
+            case "muteAllRemoteVideoStreams": {
+                boolean muted = call.argument("muted");
+                mRtcEngine.muteAllRemoteVideoStreams(muted);
+                result.success(null);
+            }
+            break;
+            case "setDefaultMuteAllRemoteVideoStreams": {
+                boolean muted = call.argument("muted");
+                mRtcEngine.setDefaultMuteAllRemoteVideoStreams(muted);
+                result.success(null);
+            }
+            break;
+
+            // Audio Routing Controller
+            case "setDefaultAudioRouteToSpeaker": {
+                boolean defaultToSpeaker = call.argument("defaultToSpeaker");
+                mRtcEngine.setDefaultAudioRoutetoSpeakerphone(defaultToSpeaker);
+                result.success(null);
+            }
+            break;
+            case "setEnableSpeakerphone": {
+                boolean enabled = call.argument("enabled");
+                mRtcEngine.setEnableSpeakerphone(enabled);
+                result.success(null);
+            }
+            break;
+            case "isSpeakerphoneEnabled": {
+                boolean enabled = mRtcEngine.isSpeakerphoneEnabled();
+                result.success(enabled);
+            }
+            break;
+
+            // Stream Fallback
+            case "setRemoteUserPriority": {
+                int uid = call.argument("uid");
+                int userPriority = call.argument("userPriority");
+                mRtcEngine.setRemoteUserPriority(uid , userPriority);
+                result.success(null);
+            }
+            case "setLocalPublishFallbackOption": {
+                int option = call.argument("option");
+                mRtcEngine.setLocalPublishFallbackOption(option);
+                result.success(null);
+            }
+            break;
+            case "setRemoteSubscribeFallbackOption": {
+                int option = call.argument("option");
+                mRtcEngine.setRemoteSubscribeFallbackOption(option);
+                result.success(null);
+            }
+            break;
+
+            // Dual-stream Mode
+            case "enableDualStreamMode": {
+                boolean enabled = call.argument("enabled");
+                mRtcEngine.enableDualStreamMode(enabled);
+                result.success(null);
+            }
+            break;
+            case "setRemoteVideoStreamType": {
+                int uid = call.argument("uid");
+                int streamType = call.argument("streamType");
+                mRtcEngine.setRemoteVideoStreamType(uid , streamType);
+                result.success(null);
+            }
+            break;
+            case "setRemoteDefaultVideoStreamType": {
+                int streamType = call.argument("streamType");
+                mRtcEngine.setRemoteDefaultVideoStreamType(streamType);
+                result.success(null);
+            }
+            break;
+
+            // Encryption
+            case "setEncryptionSecret": {
+                String secret = call.argument("secret");
+                mRtcEngine.setEncryptionSecret(secret);
+                result.success(null);
+            }
+            break;
+            case "setEncryptionMode": {
+                String encryptionMode = call.argument("encryptionMode");
+                mRtcEngine.setEncryptionMode(encryptionMode);
+                result.success(null);
+            }
+            break;
+
+            // Camera Control
+            case "switchCamera": {
+                mRtcEngine.switchCamera();
+                result.success(null);
+            }
+            break;
+
+            // Miscellaneous Methods
+            case "getSdkVersion": {
+                String version = RtcEngine.getSdkVersion();
+                result.success(version);
+            }
+            break;
+
+            default:
+                result.notImplemented();
+        }
     }
 
-    @Override
-    public void onConnectionLost() {
-      super.onConnectionLost();
-      invokeMethod("onConnectionLost", null);
+    private VideoEncoderConfiguration.ORIENTATION_MODE orientationFromValue(int value) {
+        switch (value) {
+            case 0:
+                return VideoEncoderConfiguration.ORIENTATION_MODE.ORIENTATION_MODE_ADAPTIVE;
+            case 1:
+                return VideoEncoderConfiguration.ORIENTATION_MODE.ORIENTATION_MODE_FIXED_LANDSCAPE;
+            case 2:
+                return VideoEncoderConfiguration.ORIENTATION_MODE.ORIENTATION_MODE_FIXED_PORTRAIT;
+            default:
+                return VideoEncoderConfiguration.ORIENTATION_MODE.ORIENTATION_MODE_ADAPTIVE;
+        }
     }
 
-    @Override
-    public void onNetworkTypeChanged (int type) {
-      super.onNetworkTypeChanged(type);
-      HashMap<String, Object> map = new HashMap<>();
-      map.put("type", type);
-      invokeMethod("onNetworkTypeChanged", map);
-    }
+    private final IRtcEngineEventHandler mRtcEventHandler = new IRtcEngineEventHandler() {
+        @Override
+        public void onWarning(int warn) {
+            super.onWarning(warn);
+            HashMap<String, Object> map = new HashMap<>();
+            map.put("warn" , warn);
+            invokeMethod("onWarning" , map);
+        }
 
-    @Override
-    public void onApiCallExecuted(int error, String api, String result) {
-      super.onApiCallExecuted(error, api, result);
-      HashMap<String, Object> map = new HashMap<>();
-      map.put("error", error);
-      map.put("api", api);
-      map.put("result", result);
-      invokeMethod("onApiCallExecuted", map);
-    }
+        @Override
+        public void onError(int err) {
+            super.onError(err);
+            HashMap<String, Object> map = new HashMap<>();
+            map.put("err" , err);
+            invokeMethod("onError" , map);
+        }
 
-    @Override
-    public void onTokenPrivilegeWillExpire(String token) {
-      super.onTokenPrivilegeWillExpire(token);
-      HashMap<String, Object> map = new HashMap<>();
-      map.put("token", token);
-      invokeMethod("onTokenPrivilegeWillExpire", map);
-    }
+        @Override
+        public void onJoinChannelSuccess(String channel , int uid , int elapsed) {
+            super.onJoinChannelSuccess(channel , uid , elapsed);
+            HashMap<String, Object> map = new HashMap<>();
+            map.put("channel" , channel);
+            map.put("uid" , uid);
+            map.put("elapsed" , elapsed);
+            invokeMethod("onJoinChannelSuccess" , map);
+        }
 
-    @Override
-    public void onRequestToken() {
-      super.onRequestToken();
-      invokeMethod("onRequestToken", null);
-    }
+        @Override
+        public void onRejoinChannelSuccess(String channel , int uid , int elapsed) {
+            super.onRejoinChannelSuccess(channel , uid , elapsed);
+            HashMap<String, Object> map = new HashMap<>();
+            map.put("channel" , channel);
+            map.put("uid" , uid);
+            map.put("elapsed" , elapsed);
+            invokeMethod("onRejoinChannelSuccess" , map);
+        }
 
-    @Override
-    public void onMicrophoneEnabled(boolean enabled) {
-      super.onMicrophoneEnabled(enabled);
-      HashMap<String, Object> map = new HashMap<>();
-      map.put("enabled", enabled);
-      invokeMethod("onMicrophoneEnabled", map);
-    }
+        @Override
+        public void onLeaveChannel(RtcStats stats) {
+            super.onLeaveChannel(stats);
+            HashMap<String, Object> map = new HashMap<>();
+            map.put("stats" , mapFromStats(stats));
+            invokeMethod("onLeaveChannel" , map);
+        }
 
-    @Override
-    public void onAudioVolumeIndication(AudioVolumeInfo[] speakers, int totalVolume) {
-      super.onAudioVolumeIndication(speakers, totalVolume);
-      HashMap<String, Object> map = new HashMap<>();
-      map.put("totalVolume", totalVolume);
-      map.put("speakers", arrayFromSpeakers(speakers));
-      invokeMethod("onAudioVolumeIndication", map);
-    }
+        @Override
+        public void onClientRoleChanged(int oldRole , int newRole) {
+            super.onClientRoleChanged(oldRole , newRole);
+            HashMap<String, Object> map = new HashMap<>();
+            map.put("oldRole" , oldRole);
+            map.put("newRole" , newRole);
+            invokeMethod("onClientRoleChanged" , map);
+        }
 
-    @Override
-    public void onActiveSpeaker(int uid) {
-      super.onActiveSpeaker(uid);
-      HashMap<String, Object> map = new HashMap<>();
-      map.put("uid", uid);
-      invokeMethod("onActiveSpeaker", map);
-    }
+        @Override
+        public void onUserJoined(int uid , int elapsed) {
+            super.onUserJoined(uid , elapsed);
+            HashMap<String, Object> map = new HashMap<>();
+            map.put("uid" , uid);
+            map.put("elapsed" , elapsed);
+            invokeMethod("onUserJoined" , map);
+        }
 
-    @Override
-    public void onFirstLocalAudioFrame(int elapsed) {
-      super.onFirstLocalAudioFrame(elapsed);
-      HashMap<String, Object> map = new HashMap<>();
-      map.put("elapsed", elapsed);
-      invokeMethod("onFirstLocalAudioFrame", map);
-    }
+        @Override
+        public void onUserOffline(int uid , int reason) {
+            super.onUserOffline(uid , reason);
+            HashMap<String, Object> map = new HashMap<>();
+            map.put("uid" , uid);
+            map.put("reason" , reason);
+            invokeMethod("onUserOffline" , map);
+        }
 
-    @Override
-    public void onFirstRemoteAudioFrame(int uid, int elapsed) {
-      super.onFirstRemoteAudioFrame(uid, elapsed);
-      HashMap<String, Object> map = new HashMap<>();
-      map.put("uid", uid);
-      map.put("elapsed", elapsed);
-      invokeMethod("onFirstRemoteAudioFrame", map);
-    }
+        @Override
+        public void onConnectionStateChanged(int state , int reason) {
+            super.onConnectionStateChanged(state , reason);
+            HashMap<String, Object> map = new HashMap<>();
+            map.put("state" , state);
+            map.put("reason" , reason);
+            invokeMethod("onConnectionStateChanged" , map);
+        }
 
-    @Override
-    public void onFirstRemoteAudioDecoded(int uid, int elapsed) {
-      super.onFirstRemoteAudioDecoded(uid, elapsed);
-      HashMap<String, Object> map = new HashMap<>();
-      map.put("uid", uid);
-      map.put("elapsed", elapsed);
-      invokeMethod("onFirstRemoteAudioDecoded", map);
-    }
+        @Override
+        public void onConnectionLost() {
+            super.onConnectionLost();
+            invokeMethod("onConnectionLost" , null);
+        }
 
-    @Override
-    public void onFirstLocalVideoFrame(int width, int height, int elapsed) {
-      super.onFirstLocalVideoFrame(width, height, elapsed);
-      HashMap<String, Object> map = new HashMap<>();
-      map.put("width", width);
-      map.put("height", height);
-      map.put("elapsed", elapsed);
-      invokeMethod("onFirstLocalVideoFrame", map);
-    }
+        @Override
+        public void onNetworkTypeChanged(int type) {
+            super.onNetworkTypeChanged(type);
+            HashMap<String, Object> map = new HashMap<>();
+            map.put("type" , type);
+            invokeMethod("onNetworkTypeChanged" , map);
+        }
 
-    @Override
-    public void onFirstRemoteVideoDecoded(int uid, int width, int height, int elapsed) {
-      super.onFirstRemoteVideoDecoded(uid, width, height, elapsed);
-      HashMap<String, Object> map = new HashMap<>();
-      map.put("uid", uid);
-      map.put("width", width);
-      map.put("height", height);
-      map.put("elapsed", elapsed);
-      invokeMethod("onFirstRemoteVideoDecoded", map);
-    }
+        @Override
+        public void onApiCallExecuted(int error , String api , String result) {
+            super.onApiCallExecuted(error , api , result);
+            HashMap<String, Object> map = new HashMap<>();
+            map.put("error" , error);
+            map.put("api" , api);
+            map.put("result" , result);
+            invokeMethod("onApiCallExecuted" , map);
+        }
 
-    @Override
-    public void onFirstRemoteVideoFrame(int uid, int width, int height, int elapsed) {
-      super.onFirstRemoteVideoFrame(uid, width, height, elapsed);
-      HashMap<String, Object> map = new HashMap<>();
-      map.put("uid", uid);
-      map.put("width", width);
-      map.put("height", height);
-      map.put("elapsed", elapsed);
-      invokeMethod("onFirstRemoteVideoFrame", map);
-    }
+        @Override
+        public void onTokenPrivilegeWillExpire(String token) {
+            super.onTokenPrivilegeWillExpire(token);
+            HashMap<String, Object> map = new HashMap<>();
+            map.put("token" , token);
+            invokeMethod("onTokenPrivilegeWillExpire" , map);
+        }
 
-    @Override
-    public void onUserMuteAudio(int uid, boolean muted) {
-      super.onUserMuteAudio(uid, muted);
-      HashMap<String, Object> map = new HashMap<>();
-      map.put("uid", uid);
-      map.put("muted", muted);
-      invokeMethod("onUserMuteAudio", map);
-    }
+        @Override
+        public void onRequestToken() {
+            super.onRequestToken();
+            invokeMethod("onRequestToken" , null);
+        }
 
-    @Override
-    public void onUserMuteVideo(int uid, boolean muted) {
-      super.onUserMuteVideo(uid, muted);
-      HashMap<String, Object> map = new HashMap<>();
-      map.put("uid", uid);
-      map.put("muted", muted);
-      invokeMethod("onUserMuteVideo", map);
-    }
+        @Override
+        public void onMicrophoneEnabled(boolean enabled) {
+            super.onMicrophoneEnabled(enabled);
+            HashMap<String, Object> map = new HashMap<>();
+            map.put("enabled" , enabled);
+            invokeMethod("onMicrophoneEnabled" , map);
+        }
 
-    @Override
-    public void onUserEnableVideo(int uid, boolean enabled) {
-      super.onUserEnableVideo(uid, enabled);
-      HashMap<String, Object> map = new HashMap<>();
-      map.put("uid", uid);
-      map.put("enabled", enabled);
-      invokeMethod("onUserEnableVideo", map);
-    }
+        @Override
+        public void onAudioVolumeIndication(AudioVolumeInfo[] speakers , int totalVolume) {
+            super.onAudioVolumeIndication(speakers , totalVolume);
+            HashMap<String, Object> map = new HashMap<>();
+            map.put("totalVolume" , totalVolume);
+            map.put("speakers" , arrayFromSpeakers(speakers));
+            invokeMethod("onAudioVolumeIndication" , map);
+        }
 
-    @Override
-    public void onUserEnableLocalVideo(int uid, boolean enabled) {
-      super.onUserEnableLocalVideo(uid, enabled);
-      HashMap<String, Object> map = new HashMap<>();
-      map.put("uid", uid);
-      map.put("enabled", enabled);
-      invokeMethod("onUserEnableLocalVideo", map);
-    }
+        @Override
+        public void onActiveSpeaker(int uid) {
+            super.onActiveSpeaker(uid);
+            HashMap<String, Object> map = new HashMap<>();
+            map.put("uid" , uid);
+            invokeMethod("onActiveSpeaker" , map);
+        }
 
-    @Override
-    public void onVideoSizeChanged(int uid, int width, int height, int rotation) {
-      super.onVideoSizeChanged(uid, width, height, rotation);
-      HashMap<String, Object> map = new HashMap<>();
-      map.put("uid", uid);
-      map.put("width", width);
-      map.put("height", height);
-      map.put("rotation", rotation);
-      invokeMethod("onVideoSizeChanged", map);
-    }
+        @Override
+        public void onFirstLocalAudioFrame(int elapsed) {
+            super.onFirstLocalAudioFrame(elapsed);
+            HashMap<String, Object> map = new HashMap<>();
+            map.put("elapsed" , elapsed);
+            invokeMethod("onFirstLocalAudioFrame" , map);
+        }
 
-    @Override
-    public void onRemoteVideoStateChanged(int uid, int state) {
-      super.onRemoteVideoStateChanged(uid, state);
-      HashMap<String, Object> map = new HashMap<>();
-      map.put("uid", uid);
-      map.put("state", state);
-      invokeMethod("onRemoteVideoStateChanged", map);
-    }
+        @Override
+        public void onFirstRemoteAudioFrame(int uid , int elapsed) {
+            super.onFirstRemoteAudioFrame(uid , elapsed);
+            HashMap<String, Object> map = new HashMap<>();
+            map.put("uid" , uid);
+            map.put("elapsed" , elapsed);
+            invokeMethod("onFirstRemoteAudioFrame" , map);
+        }
 
-    @Override
-    public void onLocalPublishFallbackToAudioOnly(boolean isFallbackOrRecover) {
-      super.onLocalPublishFallbackToAudioOnly(isFallbackOrRecover);
-      HashMap<String, Object> map = new HashMap<>();
-      map.put("isFallbackOrRecover", isFallbackOrRecover);
-      invokeMethod("onLocalPublishFallbackToAudioOnly", map);
-    }
+        @Override
+        public void onFirstRemoteAudioDecoded(int uid , int elapsed) {
+            super.onFirstRemoteAudioDecoded(uid , elapsed);
+            HashMap<String, Object> map = new HashMap<>();
+            map.put("uid" , uid);
+            map.put("elapsed" , elapsed);
+            invokeMethod("onFirstRemoteAudioDecoded" , map);
+        }
 
-    @Override
-    public void onRemoteSubscribeFallbackToAudioOnly(int uid, boolean isFallbackOrRecover) {
-      super.onRemoteSubscribeFallbackToAudioOnly(uid, isFallbackOrRecover);
-      HashMap<String, Object> map = new HashMap<>();
-      map.put("uid", uid);
-      map.put("isFallbackOrRecover", isFallbackOrRecover);
-      invokeMethod("onRemoteSubscribeFallbackToAudioOnly", map);
-    }
+        @Override
+        public void onFirstLocalVideoFrame(int width , int height , int elapsed) {
+            super.onFirstLocalVideoFrame(width , height , elapsed);
+            HashMap<String, Object> map = new HashMap<>();
+            map.put("width" , width);
+            map.put("height" , height);
+            map.put("elapsed" , elapsed);
+            invokeMethod("onFirstLocalVideoFrame" , map);
+        }
 
-    @Override
-    public void onAudioRouteChanged(int routing) {
-      super.onAudioRouteChanged(routing);
-      HashMap<String, Object> map = new HashMap<>();
-      map.put("routing", routing);
-      invokeMethod("onAudioRouteChanged", map);
-    }
+        @Override
+        public void onFirstRemoteVideoDecoded(int uid , int width , int height , int elapsed) {
+            super.onFirstRemoteVideoDecoded(uid , width , height , elapsed);
+            HashMap<String, Object> map = new HashMap<>();
+            map.put("uid" , uid);
+            map.put("width" , width);
+            map.put("height" , height);
+            map.put("elapsed" , elapsed);
+            invokeMethod("onFirstRemoteVideoDecoded" , map);
+        }
 
-    @Override
-    public void onCameraFocusAreaChanged(Rect rect) {
-      super.onCameraFocusAreaChanged(rect);
-      HashMap<String, Object> map = new HashMap<>();
-      map.put("rect", mapFromRect(rect));
-      invokeMethod("onCameraFocusAreaChanged", map);
-    }
+        @Override
+        public void onFirstRemoteVideoFrame(int uid , int width , int height , int elapsed) {
+            super.onFirstRemoteVideoFrame(uid , width , height , elapsed);
+            HashMap<String, Object> map = new HashMap<>();
+            map.put("uid" , uid);
+            map.put("width" , width);
+            map.put("height" , height);
+            map.put("elapsed" , elapsed);
+            invokeMethod("onFirstRemoteVideoFrame" , map);
+        }
 
-    @Override
-    public void onCameraExposureAreaChanged(Rect rect) {
-      super.onCameraExposureAreaChanged(rect);
-      HashMap<String, Object> map = new HashMap<>();
-      map.put("rect", mapFromRect(rect));
-      invokeMethod("onCameraExposureAreaChanged", map);
-    }
+        @Override
+        public void onUserMuteAudio(int uid , boolean muted) {
+            super.onUserMuteAudio(uid , muted);
+            HashMap<String, Object> map = new HashMap<>();
+            map.put("uid" , uid);
+            map.put("muted" , muted);
+            invokeMethod("onUserMuteAudio" , map);
+        }
 
-    @Override
-    public void onRtcStats(RtcStats stats) {
-      super.onRtcStats(stats);
-      HashMap<String, Object> map = new HashMap<>();
-      map.put("stats", mapFromStats(stats));
-      invokeMethod("onRtcStats", map);
-    }
+        @Override
+        public void onUserMuteVideo(int uid , boolean muted) {
+            super.onUserMuteVideo(uid , muted);
+            HashMap<String, Object> map = new HashMap<>();
+            map.put("uid" , uid);
+            map.put("muted" , muted);
+            invokeMethod("onUserMuteVideo" , map);
+        }
 
-    @Override
-    public void onLastmileQuality(int quality) {
-      super.onLastmileQuality(quality);
-      HashMap<String, Object> map = new HashMap<>();
-      map.put("quality", quality);
-      invokeMethod("onLastmileQuality", map);
-    }
+        @Override
+        public void onUserEnableVideo(int uid , boolean enabled) {
+            super.onUserEnableVideo(uid , enabled);
+            HashMap<String, Object> map = new HashMap<>();
+            map.put("uid" , uid);
+            map.put("enabled" , enabled);
+            invokeMethod("onUserEnableVideo" , map);
+        }
 
-    @Override
-    public void onNetworkQuality(int uid, int txQuality, int rxQuality) {
-      super.onNetworkQuality(uid, txQuality, rxQuality);
-      HashMap<String, Object> map = new HashMap<>();
-      map.put("uid", uid);
-      map.put("txQuality", txQuality);
-      map.put("rxQuality", rxQuality);
-      invokeMethod("onNetworkQuality", map);
-    }
+        @Override
+        public void onUserEnableLocalVideo(int uid , boolean enabled) {
+            super.onUserEnableLocalVideo(uid , enabled);
+            HashMap<String, Object> map = new HashMap<>();
+            map.put("uid" , uid);
+            map.put("enabled" , enabled);
+            invokeMethod("onUserEnableLocalVideo" , map);
+        }
 
-    @Override
-    public void onLocalVideoStats(LocalVideoStats stats) {
-      super.onLocalVideoStats(stats);
-      HashMap<String, Object> map = new HashMap<>();
-      map.put("stats", mapFromLocalVideoStats(stats));
-      invokeMethod("onLocalVideoStats", map);
-    }
+        @Override
+        public void onVideoSizeChanged(int uid , int width , int height , int rotation) {
+            super.onVideoSizeChanged(uid , width , height , rotation);
+            HashMap<String, Object> map = new HashMap<>();
+            map.put("uid" , uid);
+            map.put("width" , width);
+            map.put("height" , height);
+            map.put("rotation" , rotation);
+            invokeMethod("onVideoSizeChanged" , map);
+        }
 
-    @Override
-    public void onRemoteVideoStats(RemoteVideoStats stats) {
-      super.onRemoteVideoStats(stats);
-      HashMap<String, Object> map = new HashMap<>();
-      map.put("stats", mapFromRemoteVideoStats(stats));
-      invokeMethod("onRemoteVideoStats", map);
-    }
+        @Override
+        public void onRemoteVideoStateChanged(int uid , int state) {
+            super.onRemoteVideoStateChanged(uid , state);
+            HashMap<String, Object> map = new HashMap<>();
+            map.put("uid" , uid);
+            map.put("state" , state);
+            invokeMethod("onRemoteVideoStateChanged" , map);
+        }
 
-    @Override
-    public void onRemoteAudioStats(RemoteAudioStats stats) {
-      super.onRemoteAudioStats(stats);
-      HashMap<String, Object> map = new HashMap<>();
-      map.put("stats", mapFromRemoteAudioStats(stats));
-      invokeMethod("onRemoteAudioStats", map);
-    }
+        @Override
+        public void onLocalPublishFallbackToAudioOnly(boolean isFallbackOrRecover) {
+            super.onLocalPublishFallbackToAudioOnly(isFallbackOrRecover);
+            HashMap<String, Object> map = new HashMap<>();
+            map.put("isFallbackOrRecover" , isFallbackOrRecover);
+            invokeMethod("onLocalPublishFallbackToAudioOnly" , map);
+        }
 
-    @Override
-    public void onRemoteAudioTransportStats(int uid, int delay, int lost, int rxKBitRate) {
-      super.onRemoteAudioTransportStats(uid, delay, lost, rxKBitRate);
-      HashMap<String, Object> map = new HashMap<>();
-      map.put("uid", uid);
-      map.put("delay", delay);
-      map.put("lost", lost);
-      map.put("rxKBitRate", rxKBitRate);
-      invokeMethod("onRemoteAudioTransportStats", map);
-    }
+        @Override
+        public void onRemoteSubscribeFallbackToAudioOnly(int uid , boolean isFallbackOrRecover) {
+            super.onRemoteSubscribeFallbackToAudioOnly(uid , isFallbackOrRecover);
+            HashMap<String, Object> map = new HashMap<>();
+            map.put("uid" , uid);
+            map.put("isFallbackOrRecover" , isFallbackOrRecover);
+            invokeMethod("onRemoteSubscribeFallbackToAudioOnly" , map);
+        }
 
-    @Override
-    public void onRemoteVideoTransportStats(int uid, int delay, int lost, int rxKBitRate) {
-      super.onRemoteVideoTransportStats(uid, delay, lost, rxKBitRate);
-      HashMap<String, Object> map = new HashMap<>();
-      map.put("uid", uid);
-      map.put("delay", delay);
-      map.put("lost", lost);
-      map.put("rxKBitRate", rxKBitRate);
-      invokeMethod("onRemoteVideoTransportStats", map);
-    }
+        @Override
+        public void onAudioRouteChanged(int routing) {
+            super.onAudioRouteChanged(routing);
+            HashMap<String, Object> map = new HashMap<>();
+            map.put("routing" , routing);
+            invokeMethod("onAudioRouteChanged" , map);
+        }
 
-    @Override
-    public void onLocalVideoStateChanged(int localVideoState, int error) {
-      super.onLocalVideoStateChanged(localVideoState, error);
-      HashMap<String, Object> map = new HashMap<>();
-      map.put("localVideoState", localVideoState);
-      map.put("error", error);
-      invokeMethod("onLocalVideoStateChanged", map);
-    }
+        @Override
+        public void onCameraFocusAreaChanged(Rect rect) {
+            super.onCameraFocusAreaChanged(rect);
+            HashMap<String, Object> map = new HashMap<>();
+            map.put("rect" , mapFromRect(rect));
+            invokeMethod("onCameraFocusAreaChanged" , map);
+        }
 
-    @Override
-    public void onAudioEffectFinished(int soundId) {
-      super.onAudioEffectFinished(soundId);
-      HashMap<String, Object> map = new HashMap<>();
-      map.put("soundId", soundId);
-      invokeMethod("onAudioEffectFinished", map);
-    }
+        @Override
+        public void onCameraExposureAreaChanged(Rect rect) {
+            super.onCameraExposureAreaChanged(rect);
+            HashMap<String, Object> map = new HashMap<>();
+            map.put("rect" , mapFromRect(rect));
+            invokeMethod("onCameraExposureAreaChanged" , map);
+        }
 
-    @Override
-    public void onStreamPublished(String url, int error) {
-      super.onStreamPublished(url, error);
-      HashMap<String, Object> map = new HashMap<>();
-      map.put("url", url);
-      map.put("error", error);
-      invokeMethod("onStreamPublished", map);
-    }
+        @Override
+        public void onRtcStats(RtcStats stats) {
+            super.onRtcStats(stats);
+            HashMap<String, Object> map = new HashMap<>();
+            map.put("stats" , mapFromStats(stats));
+            invokeMethod("onRtcStats" , map);
+        }
 
-    @Override
-    public void onStreamUnpublished(String url) {
-      super.onStreamUnpublished(url);
-      HashMap<String, Object> map = new HashMap<>();
-      map.put("url", url);
-      invokeMethod("onStreamUnpublished", map);
-    }
+        @Override
+        public void onLastmileQuality(int quality) {
+            super.onLastmileQuality(quality);
+            HashMap<String, Object> map = new HashMap<>();
+            map.put("quality" , quality);
+            invokeMethod("onLastmileQuality" , map);
+        }
 
-    @Override
-    public void onTranscodingUpdated() {
-      super.onTranscodingUpdated();
-      invokeMethod("onTranscodingUpdated", null);
-    }
+        @Override
+        public void onNetworkQuality(int uid , int txQuality , int rxQuality) {
+            super.onNetworkQuality(uid , txQuality , rxQuality);
+            HashMap<String, Object> map = new HashMap<>();
+            map.put("uid" , uid);
+            map.put("txQuality" , txQuality);
+            map.put("rxQuality" , rxQuality);
+            invokeMethod("onNetworkQuality" , map);
+        }
 
-    @Override
-    public void onStreamInjectedStatus(String url, int uid, int status) {
-      super.onStreamInjectedStatus(url, uid, status);
-      HashMap<String, Object> map = new HashMap<>();
-      map.put("url", url);
-      map.put("uid", uid);
-      map.put("status", status);
-      invokeMethod("onStreamInjectedStatus", map);
-    }
+        @Override
+        public void onLocalVideoStats(LocalVideoStats stats) {
+            super.onLocalVideoStats(stats);
+            HashMap<String, Object> map = new HashMap<>();
+            map.put("stats" , mapFromLocalVideoStats(stats));
+            invokeMethod("onLocalVideoStats" , map);
+        }
 
-    @Override
-    public void onStreamMessage(int uid, int streamId, byte[] data) {
-      super.onStreamMessage(uid, streamId, data);
-      try {
-        String message = new String(data, "UTF-8");
-        HashMap<String, Object> map = new HashMap<>();
-        map.put("streamId", streamId);
-        map.put("uid", uid);
-        map.put("message", message);
-        invokeMethod("onStreamMessage", map);
-      } catch (Exception e) {
-          e.printStackTrace();
-      }
-    }
+        @Override
+        public void onRemoteVideoStats(RemoteVideoStats stats) {
+            super.onRemoteVideoStats(stats);
+            HashMap<String, Object> map = new HashMap<>();
+            map.put("stats" , mapFromRemoteVideoStats(stats));
+            invokeMethod("onRemoteVideoStats" , map);
+        }
 
-    @Override
-    public void onStreamMessageError(int uid, int streamId, int error, int missed, int cached) {
-      super.onStreamMessageError(uid, streamId, error, missed, cached);
-      HashMap<String, Object> map = new HashMap<>();
-      map.put("uid", uid);
-      map.put("streamId", streamId);
-      map.put("error", error);
-      map.put("missed", missed);
-      map.put("cached", cached);
-      invokeMethod("onStreamMessageError", map);
-    }
+        @Override
+        public void onRemoteAudioStats(RemoteAudioStats stats) {
+            super.onRemoteAudioStats(stats);
+            HashMap<String, Object> map = new HashMap<>();
+            map.put("stats" , mapFromRemoteAudioStats(stats));
+            invokeMethod("onRemoteAudioStats" , map);
+        }
 
-    @Override
-    public void onMediaEngineLoadSuccess() {
-      super.onMediaEngineLoadSuccess();
-      invokeMethod("onMediaEngineLoadSuccess", null);
-    }
+        @Override
+        public void onRemoteAudioTransportStats(int uid , int delay , int lost , int rxKBitRate) {
+            super.onRemoteAudioTransportStats(uid , delay , lost , rxKBitRate);
+            HashMap<String, Object> map = new HashMap<>();
+            map.put("uid" , uid);
+            map.put("delay" , delay);
+            map.put("lost" , lost);
+            map.put("rxKBitRate" , rxKBitRate);
+            invokeMethod("onRemoteAudioTransportStats" , map);
+        }
 
-    @Override
-    public void onMediaEngineStartCallSuccess() {
-      super.onMediaEngineStartCallSuccess();
-      invokeMethod("onMediaEngineStartCallSuccess", null);
-    }
+        @Override
+        public void onRemoteVideoTransportStats(int uid , int delay , int lost , int rxKBitRate) {
+            super.onRemoteVideoTransportStats(uid , delay , lost , rxKBitRate);
+            HashMap<String, Object> map = new HashMap<>();
+            map.put("uid" , uid);
+            map.put("delay" , delay);
+            map.put("lost" , lost);
+            map.put("rxKBitRate" , rxKBitRate);
+            invokeMethod("onRemoteVideoTransportStats" , map);
+        }
 
-    private HashMap<String, Object> mapFromStats(RtcStats stats) {
-      HashMap<String, Object> map = new HashMap<>();
-      map.put("duration", stats.totalDuration);
-      map.put("txBytes", stats.txBytes);
-      map.put("rxBytes", stats.rxBytes);
-      map.put("txAudioKBitrate", stats.txAudioKBitRate);
-      map.put("rxAudioKBitrate", stats.rxAudioKBitRate);
-      map.put("txVideoKBitrate", stats.txVideoKBitRate);
-      map.put("rxVideoKBitrate", stats.rxVideoKBitRate);
-      map.put("txPacketLossRate", stats.txPacketLossRate);
-      map.put("rxPacketLossRate", stats.rxPacketLossRate);
-      map.put("lastmileDelay", stats.lastmileDelay);
-      map.put("userCount", stats.users);
-      map.put("cpuAppUsage", stats.cpuAppUsage);
-      map.put("cpuTotalUsage", stats.cpuTotalUsage);
-      return map;
-    }
+        @Override
+        public void onLocalVideoStateChanged(int localVideoState , int error) {
+            super.onLocalVideoStateChanged(localVideoState , error);
+            HashMap<String, Object> map = new HashMap<>();
+            map.put("localVideoState" , localVideoState);
+            map.put("error" , error);
+            invokeMethod("onLocalVideoStateChanged" , map);
+        }
 
-    private HashMap<String, Object> mapFromRect(Rect rect) {
-      HashMap<String, Object> map = new HashMap<>();
+        @Override
+        public void onAudioEffectFinished(int soundId) {
+            super.onAudioEffectFinished(soundId);
+            HashMap<String, Object> map = new HashMap<>();
+            map.put("soundId" , soundId);
+            invokeMethod("onAudioEffectFinished" , map);
+        }
 
-      map.put("x", rect.left);
-      map.put("y", rect.top);
-      map.put("width", rect.width());
-      map.put("height", rect.height());
-      return map;
-    }
+        @Override
+        public void onStreamPublished(String url , int error) {
+            super.onStreamPublished(url , error);
+            HashMap<String, Object> map = new HashMap<>();
+            map.put("url" , url);
+            map.put("error" , error);
+            invokeMethod("onStreamPublished" , map);
+        }
 
-    private HashMap<String, Object> mapFromLocalVideoStats(LocalVideoStats stats) {
-      HashMap<String, Object> map = new HashMap<>();
-      map.put("sentBitrate", stats.sentBitrate);
-      map.put("sentFrameRate", stats.sentFrameRate);
-      map.put("encoderOutputFrameRate", stats.encoderOutputFrameRate);
-      map.put("rendererOutputFrameRate", stats.rendererOutputFrameRate);
-      return map;
-    }
+        @Override
+        public void onStreamUnpublished(String url) {
+            super.onStreamUnpublished(url);
+            HashMap<String, Object> map = new HashMap<>();
+            map.put("url" , url);
+            invokeMethod("onStreamUnpublished" , map);
+        }
 
-    private HashMap<String, Object> mapFromRemoteVideoStats(RemoteVideoStats stats) {
-      HashMap<String, Object> map = new HashMap<>();
-      map.put("uid", stats.uid);
-      map.put("width", stats.width);
-      map.put("height", stats.height);
-      map.put("receivedBitrate", stats.receivedBitrate);
-      map.put("decoderOutputFrameRate", stats.decoderOutputFrameRate);
-      map.put("rendererOutputFrameRate", stats.rendererOutputFrameRate);
-      map.put("rxStreamType", stats.rxStreamType);
-      return map;
-    }
+        @Override
+        public void onTranscodingUpdated() {
+            super.onTranscodingUpdated();
+            invokeMethod("onTranscodingUpdated" , null);
+        }
 
-    private HashMap<String, Object> mapFromRemoteAudioStats(RemoteAudioStats stats) {
-      HashMap<String, Object> map = new HashMap<>();
-      map.put("uid", stats.uid);
-      map.put("quality", stats.quality);
-      map.put("networkTransportDelay", stats.networkTransportDelay);
-      map.put("jitterBufferDelay", stats.jitterBufferDelay);
-      map.put("audioLossRate", stats.audioLossRate);
-      return map;
-    }
+        @Override
+        public void onStreamInjectedStatus(String url , int uid , int status) {
+            super.onStreamInjectedStatus(url , uid , status);
+            HashMap<String, Object> map = new HashMap<>();
+            map.put("url" , url);
+            map.put("uid" , uid);
+            map.put("status" , status);
+            invokeMethod("onStreamInjectedStatus" , map);
+        }
 
-    private ArrayList<HashMap<String, Object>> arrayFromSpeakers(AudioVolumeInfo[] speakers) {
-      ArrayList<HashMap<String, Object>> list = new ArrayList<>();
+        @Override
+        public void onStreamMessage(int uid , int streamId , byte[] data) {
+            super.onStreamMessage(uid , streamId , data);
+            try {
+                String message = new String(data , "UTF-8");
+                HashMap<String, Object> map = new HashMap<>();
+                map.put("streamId" , streamId);
+                map.put("uid" , uid);
+                map.put("message" , message);
+                invokeMethod("onStreamMessage" , map);
+            } catch (Exception e) {
+                e.printStackTrace();
+            }
+        }
 
-        for (AudioVolumeInfo info: speakers) {
+        @Override
+        public void onStreamMessageError(int uid , int streamId , int error , int missed ,
+                                         int cached) {
+            super.onStreamMessageError(uid , streamId , error , missed , cached);
             HashMap<String, Object> map = new HashMap<>();
-            map.put("uid", info.uid);
-            map.put("volume", info.volume);
+            map.put("uid" , uid);
+            map.put("streamId" , streamId);
+            map.put("error" , error);
+            map.put("missed" , missed);
+            map.put("cached" , cached);
+            invokeMethod("onStreamMessageError" , map);
+        }
 
-            list.add(map);
+        @Override
+        public void onMediaEngineLoadSuccess() {
+            super.onMediaEngineLoadSuccess();
+            invokeMethod("onMediaEngineLoadSuccess" , null);
         }
 
-      return list;
-    }
-  };
-
-  private BeautyOptions beautyOptionsFromMap(HashMap<String, Object> map) {
-    BeautyOptions options = new BeautyOptions();
-    options.lighteningContrastLevel = ((Double)(map.get("lighteningContrastLevel"))).intValue();
-    options.lighteningLevel = ((Double)(map.get("lighteningLevel"))).floatValue();
-    options.smoothnessLevel = ((Double)(map.get("smoothnessLevel"))).floatValue();
-    options.rednessLevel = ((Double)(map.get("rednessLevel"))).floatValue();
-    return options;
-  }
-
-  private VideoEncoderConfiguration videoEncoderConfigurationFromMap(HashMap<String, Object> map) {
-    int width = (int)(map.get("width"));
-    int height = (int)(map.get("height"));
-    int frameRate = (int)(map.get("frameRate"));
-    int bitrate = (int)(map.get("bitrate"));
-    int minBitrate = (int)(map.get("minBitrate"));
-    int orientationMode = (int)(map.get("orientationMode"));
-
-    VideoEncoderConfiguration configuration = new VideoEncoderConfiguration();
-    configuration.dimensions = new VideoEncoderConfiguration.VideoDimensions(width, height);
-    configuration.frameRate = frameRate;
-    configuration.bitrate = bitrate;
-    configuration.minBitrate = minBitrate;
-    configuration.orientationMode = orientationFromValue(orientationMode);
-
-    return configuration;
-  }
-
-  private void invokeMethod(final String method, final HashMap map) {
-    mEventHandler.post(new Runnable() {
-      @Override
-      public void run() {
-        mMethodChannel.invokeMethod(method, map);
-      }
-    });
-  }
-
-  private static class MethodResultWrapper implements MethodChannel.Result {
-    private MethodChannel.Result mResult;
-    private Handler mHandler;
-
-    MethodResultWrapper(MethodChannel.Result result, Handler handler) {
-      this.mResult = result;
-      this.mHandler = handler;
-    }
+        @Override
+        public void onMediaEngineStartCallSuccess() {
+            super.onMediaEngineStartCallSuccess();
+            invokeMethod("onMediaEngineStartCallSuccess" , null);
+        }
+
+        private HashMap<String, Object> mapFromStats(RtcStats stats) {
+            HashMap<String, Object> map = new HashMap<>();
+            map.put("duration" , stats.totalDuration);
+            map.put("txBytes" , stats.txBytes);
+            map.put("rxBytes" , stats.rxBytes);
+            map.put("txAudioKBitrate" , stats.txAudioKBitRate);
+            map.put("rxAudioKBitrate" , stats.rxAudioKBitRate);
+            map.put("txVideoKBitrate" , stats.txVideoKBitRate);
+            map.put("rxVideoKBitrate" , stats.rxVideoKBitRate);
+            map.put("txPacketLossRate" , stats.txPacketLossRate);
+            map.put("rxPacketLossRate" , stats.rxPacketLossRate);
+            map.put("lastmileDelay" , stats.lastmileDelay);
+            map.put("userCount" , stats.users);
+            map.put("cpuAppUsage" , stats.cpuAppUsage);
+            map.put("cpuTotalUsage" , stats.cpuTotalUsage);
+            return map;
+        }
+
+        private HashMap<String, Object> mapFromRect(Rect rect) {
+            HashMap<String, Object> map = new HashMap<>();
+
+            map.put("x" , rect.left);
+            map.put("y" , rect.top);
+            map.put("width" , rect.width());
+            map.put("height" , rect.height());
+            return map;
+        }
+
+        private HashMap<String, Object> mapFromLocalVideoStats(LocalVideoStats stats) {
+            HashMap<String, Object> map = new HashMap<>();
+            map.put("sentBitrate" , stats.sentBitrate);
+            map.put("sentFrameRate" , stats.sentFrameRate);
+            map.put("encoderOutputFrameRate" , stats.encoderOutputFrameRate);
+            map.put("rendererOutputFrameRate" , stats.rendererOutputFrameRate);
+            return map;
+        }
+
+        private HashMap<String, Object> mapFromRemoteVideoStats(RemoteVideoStats stats) {
+            HashMap<String, Object> map = new HashMap<>();
+            map.put("uid" , stats.uid);
+            map.put("width" , stats.width);
+            map.put("height" , stats.height);
+            map.put("receivedBitrate" , stats.receivedBitrate);
+            map.put("decoderOutputFrameRate" , stats.decoderOutputFrameRate);
+            map.put("rendererOutputFrameRate" , stats.rendererOutputFrameRate);
+            map.put("rxStreamType" , stats.rxStreamType);
+            return map;
+        }
+
+        private HashMap<String, Object> mapFromRemoteAudioStats(RemoteAudioStats stats) {
+            HashMap<String, Object> map = new HashMap<>();
+            map.put("uid" , stats.uid);
+            map.put("quality" , stats.quality);
+            map.put("networkTransportDelay" , stats.networkTransportDelay);
+            map.put("jitterBufferDelay" , stats.jitterBufferDelay);
+            map.put("audioLossRate" , stats.audioLossRate);
+            return map;
+        }
+
+        private ArrayList<HashMap<String, Object>> arrayFromSpeakers(AudioVolumeInfo[] speakers) {
+            ArrayList<HashMap<String, Object>> list = new ArrayList<>();
+
+            for (AudioVolumeInfo info : speakers) {
+                HashMap<String, Object> map = new HashMap<>();
+                map.put("uid" , info.uid);
+                map.put("volume" , info.volume);
+
+                list.add(map);
+            }
+
+            return list;
+        }
+    };
+
+    private BeautyOptions beautyOptionsFromMap(HashMap<String, Object> map) {
+        BeautyOptions options = new BeautyOptions();
+        options.lighteningContrastLevel =
+                ((Double) (map.get("lighteningContrastLevel"))).intValue();
+        options.lighteningLevel = ((Double) (map.get("lighteningLevel"))).floatValue();
+        options.smoothnessLevel = ((Double) (map.get("smoothnessLevel"))).floatValue();
+        options.rednessLevel = ((Double) (map.get("rednessLevel"))).floatValue();
+        return options;
+    }
+
+    private VideoEncoderConfiguration videoEncoderConfigurationFromMap(HashMap<String, Object> map) {
+        int width = (int) (map.get("width"));
+        int height = (int) (map.get("height"));
+        int frameRate = (int) (map.get("frameRate"));
+        int bitrate = (int) (map.get("bitrate"));
+        int minBitrate = (int) (map.get("minBitrate"));
+        int orientationMode = (int) (map.get("orientationMode"));
+
+        VideoEncoderConfiguration configuration = new VideoEncoderConfiguration();
+        configuration.dimensions = new VideoEncoderConfiguration.VideoDimensions(width , height);
+        configuration.frameRate = frameRate;
+        configuration.bitrate = bitrate;
+        configuration.minBitrate = minBitrate;
+        configuration.orientationMode = orientationFromValue(orientationMode);
+
+        return configuration;
+    }
+
+    private void invokeMethod(final String method , final HashMap map) {
+        mEventHandler.post(new Runnable() {
+            @Override
+            public void run() {
+                mMethodChannel.invokeMethod(method , map);
+            }
+        });
+    }
+
+    private static class MethodResultWrapper implements MethodChannel.Result {
+        private MethodChannel.Result mResult;
+        private Handler mHandler;
+
+        MethodResultWrapper(MethodChannel.Result result , Handler handler) {
+            this.mResult = result;
+            this.mHandler = handler;
+        }
 
-    @Override
-    public void success(final Object result) {
-      mHandler.post(new Runnable() {
         @Override
-        public void run() {
-          mResult.success(result);
+        public void success(final Object result) {
+            mHandler.post(new Runnable() {
+                @Override
+                public void run() {
+                    mResult.success(result);
+                }
+            });
         }
-      });
-    }
 
-    @Override
-    public void error(final String errorCode, final String errorMessage, final Object errorDetails) {
-      mHandler.post(new Runnable() {
         @Override
-        public void run() {
-          mResult.error(errorCode, errorMessage, errorDetails);
+        public void error(final String errorCode , final String errorMessage ,
+                          final Object errorDetails) {
+            mHandler.post(new Runnable() {
+                @Override
+                public void run() {
+                    mResult.error(errorCode , errorMessage , errorDetails);
+                }
+            });
         }
-      });
-    }
 
-    @Override
-    public void notImplemented() {
-      mHandler.post(new Runnable() {
         @Override
-        public void run() {
-          mResult.notImplemented();
+        public void notImplemented() {
+            mHandler.post(new Runnable() {
+                @Override
+                public void run() {
+                    mResult.notImplemented();
+                }
+            });
         }
-      });
     }
-  }
 }
diff --git a/ios/Classes/AgoraRtcEnginePlugin.m b/ios/Classes/AgoraRtcEnginePlugin.m
index bf4904e29..476ac32d7 100644
--- a/ios/Classes/AgoraRtcEnginePlugin.m
+++ b/ios/Classes/AgoraRtcEnginePlugin.m
@@ -95,15 +95,19 @@ - (void)handleMethodCall:(FlutterMethodCall*)call result:(FlutterResult)result {
   if ([@"create" isEqualToString:method]) {
     NSString *appId = [self stringFromArguments:arguments key:@"appId"];
     self.agoraRtcEngine = [AgoraRtcEngineKit sharedEngineWithAppId:appId delegate:self];
+    result(nil);
   } else if ([@"destroy" isEqualToString:method]) {
     self.agoraRtcEngine = nil;
     [AgoraRtcEngineKit destroy];
+    result(nil);
   } else if ([@"setChannelProfile" isEqualToString:method]) {
     NSInteger profile = [self intFromArguments:arguments key:@"profile"];
     [self.agoraRtcEngine setChannelProfile:profile];
+    result(nil);
   } else if ([@"setClientRole" isEqualToString:method]) {
     NSInteger role = [self intFromArguments:arguments key:@"role"];
     [self.agoraRtcEngine setClientRole:role];
+    result(nil);
   } else if ([@"joinChannel" isEqualToString:method]) {
     NSString *token = [self stringFromArguments:arguments key:@"token"];
     NSString *channel = [self stringFromArguments:arguments key:@"channelId"];
@@ -111,80 +115,92 @@ - (void)handleMethodCall:(FlutterMethodCall*)call result:(FlutterResult)result {
     NSInteger uid = [self intFromArguments:arguments key:@"uid"];
     
     [self.agoraRtcEngine joinChannelByToken:token channelId:channel info:info uid:uid  joinSuccess:nil];
-    if (result) {
-      result([NSNumber numberWithBool:YES]);
-    }
+    result([NSNumber numberWithBool:YES]);
   } else if ([@"leaveChannel" isEqualToString:method]) {
     BOOL success = (0 == [self.agoraRtcEngine leaveChannel:nil]);
-    if (result) {
-      result([NSNumber numberWithBool:success]);
-    }
+    result([NSNumber numberWithBool:success]);
   } else if ([@"renewToken" isEqualToString:method]) {
     NSString *token = [self stringFromArguments:arguments key:@"token"];
     [self.agoraRtcEngine renewToken:token];
+    result(nil);
   } else if ([@"enableWebSdkInteroperability" isEqualToString:method]) {
     BOOL enabled = [self boolFromArguments:arguments key:@"enabled"];
     [self.agoraRtcEngine enableWebSdkInteroperability:enabled];
+    result(nil);
   } else if ([@"getConnectionState" isEqualToString:method]) {
     AgoraConnectionStateType state = [self.agoraRtcEngine getConnectionState];
-    if (result) {
-      result([NSNumber numberWithInteger:state]);
-    }
+    result([NSNumber numberWithInteger:state]);
   }
   // Core Audio
   else if ([@"enableAudio" isEqualToString:method]) {
     [self.agoraRtcEngine enableAudio];
+    result(nil);
   } else if ([@"disableAudio" isEqualToString:method]) {
     [self.agoraRtcEngine disableAudio];
+    result(nil);
   } else if ([@"setAudioProfile" isEqualToString:method]) {
     NSInteger profile = [self intFromArguments:arguments key:@"profile"];
     NSInteger scenario = [self intFromArguments:arguments key:@"scenario"];
     [self.agoraRtcEngine setAudioProfile:profile scenario:scenario];
+    result(nil);
   } else if ([@"setAudioProfile" isEqualToString:method]) {
     NSInteger profile = [self intFromArguments:arguments key:@"profile"];
     NSInteger scenario = [self intFromArguments:arguments key:@"scenario"];
     [self.agoraRtcEngine setAudioProfile:profile scenario:scenario];
+    result(nil);
   } else if ([@"adjustRecordingSignalVolume" isEqualToString:method]) {
     NSInteger volume = [self intFromArguments:arguments key:@"volume"];
     [self.agoraRtcEngine adjustRecordingSignalVolume:volume];
+    result(nil);
   } else if ([@"adjustPlaybackSignalVolume" isEqualToString:method]) {
     NSInteger volume = [self intFromArguments:arguments key:@"volume"];
     [self.agoraRtcEngine adjustPlaybackSignalVolume:volume];
+    result(nil);
   } else if ([@"enableAudioVolumeIndication" isEqualToString:method]) {
     NSInteger interval = [self intFromArguments:arguments key:@"interval"];
     NSInteger smooth = [self intFromArguments:arguments key:@"smooth"];
     [self.agoraRtcEngine enableAudioVolumeIndication:interval smooth:smooth];
+    result(nil);
   } else if ([@"enableLocalAudio" isEqualToString:method]) {
     BOOL enabled = [self boolFromArguments:arguments key:@"enabled"];
     [self.agoraRtcEngine enableLocalAudio:enabled];
+    result(nil);
   } else if ([@"muteLocalAudioStream" isEqualToString:method]) {
     BOOL muted = [self boolFromArguments:arguments key:@"muted"];
     [self.agoraRtcEngine muteLocalAudioStream:muted];
+    result(nil);
   } else if ([@"muteRemoteAudioStream" isEqualToString:method]) {
     NSInteger uid = [self intFromArguments:arguments key:@"uid"];
     BOOL muted = [self boolFromArguments:arguments key:@"muted"];
     [self.agoraRtcEngine muteRemoteAudioStream:uid mute:muted];
+    result(nil);
   } else if ([@"muteAllRemoteAudioStreams" isEqualToString:method]) {
     BOOL muted = [self boolFromArguments:arguments key:@"muted"];
     [self.agoraRtcEngine muteAllRemoteAudioStreams:muted];
+    result(nil);
   } else if ([@"setDefaultMuteAllRemoteAudioStreams" isEqualToString:method]) {
     BOOL muted = [self boolFromArguments:arguments key:@"muted"];
     [self.agoraRtcEngine setDefaultMuteAllRemoteAudioStreams:muted];
+    result(nil);
   }
   // Core Video
   else if ([@"enableVideo" isEqualToString:method]) {
     [self.agoraRtcEngine enableVideo];
+    result(nil);
   } else if ([@"disableVideo" isEqualToString:method]) {
     [self.agoraRtcEngine disableVideo];
+    result(nil);
   } else if ([@"setVideoEncoderConfiguration" isEqualToString:method]) {
     NSDictionary *configDic = [self dictionaryFromArguments:arguments key:@"config"];
     AgoraVideoEncoderConfiguration *config = [self videoEncoderConfigurationFromDic:configDic];
     [self.agoraRtcEngine setVideoEncoderConfiguration:config];
+    result(nil);
   } else if ([@"removeNativeView" isEqualToString:method]) {
     NSString *viewId = [self stringFromArguments:arguments key:@"viewId"];
     if (viewId.length) {
       [self.rendererViews removeObjectForKey:viewId];
     }
+    result(nil);
   } else if ([@"setupLocalVideo" isEqualToString:method]) {
     NSInteger viewId = [self intFromArguments:arguments key:@"viewId"];
     UIView *view = [AgoraRtcEnginePlugin viewForId:@(viewId)];
@@ -194,6 +210,7 @@ - (void)handleMethodCall:(FlutterMethodCall*)call result:(FlutterResult)result {
     canvas.view = view;
     canvas.renderMode = renderType;
     [self.agoraRtcEngine setupLocalVideo:canvas];
+    result(nil);
   } else if ([@"setupRemoteVideo" isEqualToString:method]) {
     NSInteger viewId = [self intFromArguments:arguments key:@"viewId"];
     UIView *view = [AgoraRtcEnginePlugin viewForId:@(viewId)];
@@ -205,33 +222,43 @@ - (void)handleMethodCall:(FlutterMethodCall*)call result:(FlutterResult)result {
     canvas.renderMode = renderType;
     canvas.uid = uid;
     [self.agoraRtcEngine setupRemoteVideo:canvas];
+    result(nil);
   } else if ([@"setLocalRenderMode" isEqualToString:method]) {
     NSInteger mode = [self intFromArguments:arguments key:@"mode"];
     [self.agoraRtcEngine setLocalRenderMode:mode];
+    result(nil);
   } else if ([@"setRemoteRenderMode" isEqualToString:method]) {
     NSInteger uid = [self intFromArguments:arguments key:@"uid"];
     NSInteger mode = [self intFromArguments:arguments key:@"mode"];
     [self.agoraRtcEngine setRemoteRenderMode:uid mode:mode];
+    result(nil);
   } else if ([@"startPreview" isEqualToString:method]) {
     [self.agoraRtcEngine startPreview];
+    result(nil);
   } else if ([@"stopPreview" isEqualToString:method]) {
     [self.agoraRtcEngine stopPreview];
+    result(nil);
   } else if ([@"enableLocalVideo" isEqualToString:method]) {
     BOOL enabled = [self boolFromArguments:arguments key:@"enabled"];
     [self.agoraRtcEngine enableLocalVideo:enabled];
+    result(nil);
   } else if ([@"muteLocalVideoStream" isEqualToString:method]) {
     BOOL muted = [self boolFromArguments:arguments key:@"muted"];
     [self.agoraRtcEngine muteLocalVideoStream:muted];
+    result(nil);
   } else if ([@"muteRemoteVideoStream" isEqualToString:method]) {
     NSInteger uid = [self intFromArguments:arguments key:@"uid"];
     BOOL muted = [self boolFromArguments:arguments key:@"muted"];
     [self.agoraRtcEngine muteRemoteVideoStream:uid mute:muted];
+    result(nil);
   } else if ([@"muteAllRemoteVideoStreams" isEqualToString:method]) {
     BOOL muted = [self boolFromArguments:arguments key:@"muted"];
     [self.agoraRtcEngine muteAllRemoteVideoStreams:muted];
+    result(nil);
   } else if ([@"setDefaultMuteAllRemoteVideoStreams" isEqualToString:method]) {
     BOOL muted = [self boolFromArguments:arguments key:@"muted"];
     [self.agoraRtcEngine setDefaultMuteAllRemoteVideoStreams:muted];
+    result(nil);
   }
   
   // Video Pre-process and Post-process
@@ -240,69 +267,75 @@ - (void)handleMethodCall:(FlutterMethodCall*)call result:(FlutterResult)result {
     NSDictionary *optionsDic = [self dictionaryFromArguments:arguments key:@"options"];
     AgoraBeautyOptions *options = [self beautyOptionsFromDic:optionsDic];
     [self.agoraRtcEngine setBeautyEffectOptions:enabled options:options];
+    result(nil);
   }
 
   // Audio Routing Controller
   else if ([@"setDefaultAudioRouteToSpeaker" isEqualToString:method]) {
     BOOL defaultToSpeaker = [self boolFromArguments:arguments key:@"defaultToSpeaker"];
     [self.agoraRtcEngine setDefaultAudioRouteToSpeakerphone:defaultToSpeaker];
+    result(nil);
   } else if ([@"setEnableSpeakerphone" isEqualToString:method]) {
     BOOL enabled = [self boolFromArguments:arguments key:@"enabled"];
     [self.agoraRtcEngine setEnableSpeakerphone:enabled];
+    result(nil);
   } else if ([@"isSpeakerphoneEnabled" isEqualToString:method]) {
     BOOL enable = [self.agoraRtcEngine isSpeakerphoneEnabled];
-    if (result) {
-      result([NSNumber numberWithBool:enable]);
-    }
+    result([NSNumber numberWithBool:enable]);
   }
   // Stream Fallback
   else if ([@"setRemoteUserPriority" isEqualToString:method]) {
     NSInteger uid = [self intFromArguments:arguments key:@"uid"];
     AgoraUserPriority priority = [self intFromArguments:arguments key:@"userPriority"];
     [self.agoraRtcEngine setRemoteUserPriority:uid type:priority];
+    result(nil);
   } else if ([@"setLocalPublishFallbackOption" isEqualToString:method]) {
     NSInteger option = [self intFromArguments:arguments key:@"option"];
     [self.agoraRtcEngine setLocalPublishFallbackOption:option];
+    result(nil);
   } else if ([@"setRemoteSubscribeFallbackOption" isEqualToString:method]) {
     NSInteger option = [self intFromArguments:arguments key:@"option"];
     [self.agoraRtcEngine setRemoteSubscribeFallbackOption:option];
+    result(nil);
   }
   // Dual-stream Mode
   else if ([@"enableDualStreamMode" isEqualToString:method]) {
     BOOL enabled = [self boolFromArguments:arguments key:@"enabled"];
     [self.agoraRtcEngine enableDualStreamMode:enabled];
+    result(nil);
   } else if ([@"setRemoteVideoStreamType" isEqualToString:method]) {
     NSInteger uid = [self intFromArguments:arguments key:@"uid"];
     NSInteger streamType = [self intFromArguments:arguments key:@"streamType"];
     [self.agoraRtcEngine setRemoteVideoStream:uid type:streamType];
+    result(nil);
   } else if ([@"setRemoteDefaultVideoStreamType" isEqualToString:method]) {
     NSInteger streamType = [self intFromArguments:arguments key:@"streamType"];
     [self.agoraRtcEngine setRemoteDefaultVideoStreamType:streamType];
+    result(nil);
   }
   // Encryption
   else if ([@"setEncryptionSecret" isEqualToString:method]) {
     NSString *secret = [self stringFromArguments:arguments key:@"secret"];
     [self.agoraRtcEngine setEncryptionSecret:secret];
+    result(nil);
   } else if ([@"setEncryptionMode" isEqualToString:method]) {
     NSString *encryptionMode = [self stringFromArguments:arguments key:@"encryptionMode"];
     [self.agoraRtcEngine setEncryptionMode:encryptionMode];
+    result(nil);
   }
   // Camera Control
   else if ([@"switchCamera" isEqualToString:method]) {
     [self.agoraRtcEngine switchCamera];
+    result(nil);
   }
   // Miscellaneous Methods
   else if ([@"getSdkVersion" isEqualToString:method]) {
     NSString *version = [AgoraRtcEngineKit getSdkVersion];
-    if (result) {
-      result(version);
-    }
+    result(version);
   }
   
   else {
-    if (result) {
-      result(FlutterMethodNotImplemented);
-    }
+    result(FlutterMethodNotImplemented);
   }
 }