Update iOS AppRTCDemo to use level controller.

webrtc/examples/objc/AppRTCDemo/ARDAppClient.m

 /*
  *  Copyright 2014 The WebRTC Project Authors. All rights reserved.
  *
  *  Use of this source code is governed by a BSD-style license
  *  that can be found in the LICENSE file in the root of the source
  *  tree. An additional intellectual property rights grant can be found
  *  in the file PATENTS.  All contributing project authors may
  *  be found in the AUTHORS file in the root of the source tree.
  */
 
@@ skipping 113 matching lines @@
 @synthesize isInitiator = _isInitiator;
 @synthesize iceServers = _iceServers;
 @synthesize webSocketURL = _websocketURL;
 @synthesize webSocketRestURL = _websocketRestURL;
 @synthesize defaultPeerConnectionConstraints =
     _defaultPeerConnectionConstraints;
 @synthesize isLoopback = _isLoopback;
 @synthesize isAudioOnly = _isAudioOnly;
 @synthesize shouldMakeAecDump = _shouldMakeAecDump;
 @synthesize isAecDumpActive = _isAecDumpActive;
+@synthesize shouldUseLevelControl = _shouldUseLevelControl;
 
 - (instancetype)init {
   if (self = [super init]) {
     _roomServerClient = [[ARDAppEngineClient alloc] init];
     NSURL *turnRequestURL = [NSURL URLWithString:kARDTurnRequestUrl];
     _turnClient = [[ARDCEODTURNClient alloc] initWithURL:turnRequestURL];
     [self configure];
   }
   return self;
 }
@@ skipping 72 matching lines @@
   if (_state == state) {
     return;
   }
   _state = state;
   [_delegate appClient:self didChangeState:_state];
 }
 
 - (void)connectToRoomWithId:(NSString *)roomId
                  isLoopback:(BOOL)isLoopback
                 isAudioOnly:(BOOL)isAudioOnly
-          shouldMakeAecDump:(BOOL)shouldMakeAecDump {
+          shouldMakeAecDump:(BOOL)shouldMakeAecDump
+      shouldUseLevelControl:(BOOL)shouldUseLevelControl {
   NSParameterAssert(roomId.length);
   NSParameterAssert(_state == kARDAppClientStateDisconnected);
   _isLoopback = isLoopback;
   _isAudioOnly = isAudioOnly;
   _shouldMakeAecDump = shouldMakeAecDump;
+  _shouldUseLevelControl = shouldUseLevelControl;
   self.state = kARDAppClientStateConnecting;
 
 #if defined(WEBRTC_IOS)
   if (kARDAppClientEnableTracing) {
     NSString *filePath = [self documentsFilePathForFileName:@"webrtc-trace.txt"];
     RTCStartInternalCapture(filePath);
   }
 #endif
 
   // Request TURN.
@@ skipping 440 matching lines @@
                              streamId:kARDMediaStreamId];
   RTCVideoTrack *track = [self createLocalVideoTrack];
   if (track) {
     sender.track = track;
     [_delegate appClient:self didReceiveLocalVideoTrack:track];
   }
   return sender;
 }
 
 - (RTCRtpSender *)createAudioSender {
+  RTCMediaConstraints *constraints = [self defaultMediaAudioConstraints];
+  RTCAudioSource *source = [_factory audioSourceWithConstraints:constraints];
+  RTCAudioTrack *track = [_factory audioTrackWithSource:source
+                                                trackId:kARDAudioTrackId];
   RTCRtpSender *sender =
       [_peerConnection senderWithKind:kRTCMediaStreamTrackKindAudio
                              streamId:kARDMediaStreamId];
-  RTCAudioTrack *track = [_factory audioTrackWithTrackId:kARDAudioTrackId];
   sender.track = track;
   return sender;
 }
 
 - (RTCVideoTrack *)createLocalVideoTrack {
   RTCVideoTrack* localVideoTrack = nil;
   // The iOS simulator doesn't provide any sort of camera capture
   // support or emulation (http://goo.gl/rHAnC1) so don't bother
   // trying to open a local stream.
   // TODO(tkchin): local video capture for OSX. See
@@ skipping 31 matching lines @@
     }
   }
   [_channel registerForRoomId:_roomId clientId:_clientId];
   if (_isLoopback) {
     [_loopbackChannel registerForRoomId:_roomId clientId:@"LOOPBACK_CLIENT_ID"];
   }
 }
 
 #pragma mark - Defaults
 
+ - (RTCMediaConstraints *)defaultMediaAudioConstraints {
+   NSString *valueLevelControl = _shouldUseLevelControl ?
+       kRTCMediaConstraintsValueTrue : kRTCMediaConstraintsValueFalse;
+   NSDictionary *mandatoryConstraints = @{ kRTCMediaConstraintsLevelControl : valueLevelControl };
+   RTCMediaConstraints* constraints =
+       [[RTCMediaConstraints alloc]  initWithMandatoryConstraints:mandatoryConstraints
+                                              optionalConstraints:nil];
+   return constraints;
+}
+
 - (RTCMediaConstraints *)defaultMediaStreamConstraints {
   RTCMediaConstraints* constraints =
       [[RTCMediaConstraints alloc]
           initWithMandatoryConstraints:nil
                    optionalConstraints:nil];
   return constraints;
 }
 
 - (RTCMediaConstraints *)defaultAnswerConstraints {
   return [self defaultOfferConstraints];
@@ skipping 81 matching lines @@
                                          code:kARDAppClientErrorInvalidRoom
                                      userInfo:@{
         NSLocalizedDescriptionKey: @"Invalid room.",
       }];
       break;
   }
   return error;
 }
 
 @end