Support delayed AudioUnit initialization.

webrtc/examples/objc/AppRTCDemo/ios/ARDMainView.m

 /*
  *  Copyright 2015 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.
  */
 
 #import "ARDMainView.h"
 
-#import <AVFoundation/AVFoundation.h>
-
 #import "UIImage+ARDUtilities.h"
 
 // TODO(tkchin): retrieve status bar height dynamically.
 static CGFloat const kStatusBarHeight = 20;
 
 static CGFloat const kRoomTextButtonSize = 40;
 static CGFloat const kRoomTextFieldHeight = 40;
 static CGFloat const kRoomTextFieldMargin = 8;
 static CGFloat const kCallControlMargin = 8;
 static CGFloat const kAppLabelHeight = 20;
@@ skipping 92 matching lines @@
 @end
 
 @implementation ARDMainView {
   UILabel *_appLabel;
   ARDRoomTextField *_roomText;
   UILabel *_callOptionsLabel;
   UISwitch *_audioOnlySwitch;
   UILabel *_audioOnlyLabel;
   UISwitch *_loopbackSwitch;
   UILabel *_loopbackLabel;
+  UISwitch *_audioConfigDelaySwitch;
+  UILabel *_audioConfigDelayLabel;
   UIButton *_startCallButton;
   UIButton *_audioLoopButton;
-  AVAudioPlayer *_audioPlayer;
 }
 
 @synthesize delegate = _delegate;
+@synthesize isAudioLoopPlaying = _isAudioLoopPlaying;
 
 - (instancetype)initWithFrame:(CGRect)frame {
   if (self = [super initWithFrame:frame]) {
-    NSString *audioFilePath =
-        [[NSBundle mainBundle] pathForResource:@"mozart" ofType:@"mp3"];
-    NSURL *audioFileURL = [NSURL URLWithString:audioFilePath];
-    _audioPlayer = [[AVAudioPlayer alloc] initWithContentsOfURL:audioFileURL
-                                                          error:nil];
-    _audioPlayer.numberOfLoops = -1;
-    _audioPlayer.volume = 1.0;
-    [_audioPlayer prepareToPlay];
-
     _appLabel = [[UILabel alloc] initWithFrame:CGRectZero];
     _appLabel.text = @"AppRTCDemo";
     _appLabel.font = [UIFont fontWithName:@"Roboto" size:34];
     _appLabel.textColor = [UIColor colorWithWhite:0 alpha:.2];
     [_appLabel sizeToFit];
     [self addSubview:_appLabel];
 
     _roomText = [[ARDRoomTextField alloc] initWithFrame:CGRectZero];
     [self addSubview:_roomText];
 
@@ skipping 22 matching lines @@
     [_loopbackSwitch sizeToFit];
     [self addSubview:_loopbackSwitch];
 
     _loopbackLabel = [[UILabel alloc] initWithFrame:CGRectZero];
     _loopbackLabel.text = @"Loopback mode";
     _loopbackLabel.font = controlFont;
     _loopbackLabel.textColor = controlFontColor;
     [_loopbackLabel sizeToFit];
     [self addSubview:_loopbackLabel];
 
+    _audioConfigDelaySwitch = [[UISwitch alloc] initWithFrame:CGRectZero];
+    [_audioConfigDelaySwitch sizeToFit];
+    _audioConfigDelaySwitch.on = YES;
+    [self addSubview:_audioConfigDelaySwitch];
+
+    _audioConfigDelayLabel = [[UILabel alloc] initWithFrame:CGRectZero];
+    _audioConfigDelayLabel.text = @"Delay audio config";
+    _audioConfigDelayLabel.font = controlFont;
+    _audioConfigDelayLabel.textColor = controlFontColor;
+    [_audioConfigDelayLabel sizeToFit];
+    [self addSubview:_audioConfigDelayLabel];
+
     _startCallButton = [UIButton buttonWithType:UIButtonTypeSystem];
     _startCallButton.backgroundColor = [UIColor blueColor];
     _startCallButton.layer.cornerRadius = 10;
     _startCallButton.clipsToBounds = YES;
     _startCallButton.contentEdgeInsets = UIEdgeInsetsMake(5, 10, 5, 10);
     [_startCallButton setTitle:@"Start call"
                       forState:UIControlStateNormal];
     _startCallButton.titleLabel.font = controlFont;
     [_startCallButton setTitleColor:[UIColor whiteColor]
                            forState:UIControlStateNormal];
@@ skipping 19 matching lines @@
     [_audioLoopButton addTarget:self
                          action:@selector(onToggleAudioLoop:)
                forControlEvents:UIControlEventTouchUpInside];
     [self addSubview:_audioLoopButton];
 
     self.backgroundColor = [UIColor whiteColor];
   }
   return self;
 }
 
+- (void)setIsAudioLoopPlaying:(BOOL)isAudioLoopPlaying {
+  if (_isAudioLoopPlaying == isAudioLoopPlaying) {
+    return;
+  }
+  _isAudioLoopPlaying = isAudioLoopPlaying;
+  [self updateAudioLoopButton];
+}
+
 - (void)layoutSubviews {
   CGRect bounds = self.bounds;
   CGFloat roomTextWidth = bounds.size.width - 2 * kRoomTextFieldMargin;
   CGFloat roomTextHeight = [_roomText sizeThatFits:bounds.size].height;
   _roomText.frame = CGRectMake(kRoomTextFieldMargin,
                                kStatusBarHeight + kRoomTextFieldMargin,
                                roomTextWidth,
                                roomTextHeight);
   _appLabel.center = CGPointMake(CGRectGetMidX(bounds), CGRectGetMidY(bounds));
 
@@ skipping 21 matching lines @@
   CGRect loopbackModeRect = CGRectMake(kCallControlMargin * 3,
                                        loopbackModeTop,
                                        _loopbackSwitch.frame.size.width,
                                        _loopbackSwitch.frame.size.height);
   _loopbackSwitch.frame = loopbackModeRect;
   CGFloat loopbackModeLabelCenterX = CGRectGetMaxX(loopbackModeRect) +
       kCallControlMargin + _loopbackLabel.frame.size.width / 2;
   _loopbackLabel.center = CGPointMake(loopbackModeLabelCenterX,
                                       CGRectGetMidY(loopbackModeRect));
 
+  CGFloat audioConfigDelayTop =
+      CGRectGetMaxY(_loopbackSwitch.frame) + kCallControlMargin;
+  CGRect audioConfigDelayRect =
+      CGRectMake(kCallControlMargin * 3,
+                 audioConfigDelayTop,
+                 _audioConfigDelaySwitch.frame.size.width,
+                 _audioConfigDelaySwitch.frame.size.height);
+  _audioConfigDelaySwitch.frame = audioConfigDelayRect;
+  CGFloat audioConfigDelayLabelCenterX = CGRectGetMaxX(audioConfigDelayRect) +
+      kCallControlMargin + _audioConfigDelayLabel.frame.size.width / 2;
+  _audioConfigDelayLabel.center =
+      CGPointMake(audioConfigDelayLabelCenterX,
+                  CGRectGetMidY(audioConfigDelayRect));
+
   CGFloat audioLoopTop =
-     CGRectGetMaxY(loopbackModeRect) + kCallControlMargin * 3;
+     CGRectGetMaxY(audioConfigDelayRect) + kCallControlMargin * 3;
   _audioLoopButton.frame = CGRectMake(kCallControlMargin,
                                       audioLoopTop,
                                       _audioLoopButton.frame.size.width,
                                       _audioLoopButton.frame.size.height);
 
   CGFloat startCallTop =
       CGRectGetMaxY(_audioLoopButton.frame) + kCallControlMargin * 3;
   _startCallButton.frame = CGRectMake(kCallControlMargin,
                                       startCallTop,
                                       _startCallButton.frame.size.width,
                                       _startCallButton.frame.size.height);
 }
 
 #pragma mark - Private
 
 - (void)updateAudioLoopButton {
-  if (_audioPlayer.playing) {
+  if (_isAudioLoopPlaying) {
     _audioLoopButton.backgroundColor = [UIColor redColor];
     [_audioLoopButton setTitle:@"Stop sound"
                       forState:UIControlStateNormal];
     [_audioLoopButton sizeToFit];
   } else {
     _audioLoopButton.backgroundColor = [UIColor greenColor];
     [_audioLoopButton setTitle:@"Play sound"
                       forState:UIControlStateNormal];
     [_audioLoopButton sizeToFit];
   }
 }
 
 - (void)onToggleAudioLoop:(id)sender {
-  if (_audioPlayer.playing) {
-    [_audioPlayer stop];
-  } else {
-    [_audioPlayer play];
-  }
-  [self updateAudioLoopButton];
+  [_delegate mainViewDidToggleAudioLoop:self];
 }
 
 - (void)onStartCall:(id)sender {
   NSString *room = _roomText.roomText;
   // If this is a loopback call, allow a generated room name.
   if (!room.length && _loopbackSwitch.isOn) {
     room = [[NSUUID UUID] UUIDString];
   }
   room = [room stringByReplacingOccurrencesOfString:@"-" withString:@""];
   [_delegate mainView:self
-         didInputRoom:room
-           isLoopback:_loopbackSwitch.isOn
-          isAudioOnly:_audioOnlySwitch.isOn];
+                didInputRoom:room
+                  isLoopback:_loopbackSwitch.isOn
+                 isAudioOnly:_audioOnlySwitch.isOn
+      shouldDelayAudioConfig:_audioConfigDelaySwitch.isOn];
 }
 
 @end