Fixing crash in Mac client when no cameras are available.

Bug: webrtc:8348
Change-Id: Ibf84ca76812d8c002fae9bd7bcf616abc53c78b1
Reviewed-on: https://webrtc-review.googlesource.com/7340
Reviewed-by: Kári Helgason <kthelgason@webrtc.org>
Reviewed-by: Daniela Jovanoska Petrenko <denicija@webrtc.org>
Commit-Queue: Peter Hanspers <peterhanspers@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#20392}

examples/objc/AppRTCMobile/ARDCaptureController.m

@@ -11,6 +11,7 @@
 #import "ARDCaptureController.h"
 
 #import "ARDSettingsModel.h"
+#import "WebRTC/RTCLogging.h"
 
 @implementation ARDCaptureController {
   RTCCameraVideoCapturer *_capturer;
@@ -34,6 +35,14 @@
       _usingFrontCamera ? AVCaptureDevicePositionFront : AVCaptureDevicePositionBack;
   AVCaptureDevice *device = [self findDeviceForPosition:position];
   AVCaptureDeviceFormat *format = [self selectFormatForDevice:device];
+
+  if (format == nil) {
+    RTCLogError(@"No valid formats for device %@", device);
+    NSAssert(NO, @"");
+
+    return;
+  }
+
   NSInteger fps = [self selectFpsForFormat:format];
 
   [_capturer startCaptureWithDevice:device format:format fps:fps];
@@ -77,7 +86,6 @@
     }
   }
 
-  NSAssert(selectedFormat != nil, @"No suitable capture format found.");
   return selectedFormat;
 }
 

examples/objc/AppRTCMobile/ARDSettingsModel.m

@@ -151,11 +151,11 @@ NS_ASSUME_NONNULL_BEGIN
 #pragma mark -
 
 - (NSString *)defaultVideoResolutionSetting {
-  return [self availableVideoResolutions][0];
+  return [self availableVideoResolutions].firstObject;
 }
 
 - (RTCVideoCodecInfo *)defaultVideoCodecSetting {
-  return [self availableVideoCodecs][0];
+  return [self availableVideoCodecs].firstObject;
 }
 
 - (int)videoResolutionComponentAtIndex:(int)index inString:(NSString *)resolution {
@@ -170,11 +170,21 @@ NS_ASSUME_NONNULL_BEGIN
 }
 
 - (void)registerStoreDefaults {
+  NSString *defaultVideoResolutionSetting = [self defaultVideoResolutionSetting];
+  BOOL audioOnly = (defaultVideoResolutionSetting.length == 0);
+
+// 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.
+#if TARGET_IPHONE_SIMULATOR
+  audioOnly = YES;
+#endif
+
   NSData *codecData = [NSKeyedArchiver archivedDataWithRootObject:[self defaultVideoCodecSetting]];
   [ARDSettingsStore setDefaultsForVideoResolution:[self defaultVideoResolutionSetting]
                                        videoCodec:codecData
                                           bitrate:nil
-                                        audioOnly:NO
+                                        audioOnly:audioOnly
                                     createAecDump:NO
                                useLevelController:NO
                              useManualAudioConfig:YES];

examples/objc/AppRTCMobile/ARDSettingsStore.m

@@ -35,15 +35,20 @@ NS_ASSUME_NONNULL_BEGIN
                    useLevelController:(BOOL)useLevelController
                  useManualAudioConfig:(BOOL)useManualAudioConfig {
   NSMutableDictionary<NSString *, id> *defaultsDictionary = [@{
-    kVideoResolutionKey : videoResolution,
-    kVideoCodecKey : videoCodec,
     kAudioOnlyKey : @(audioOnly),
     kCreateAecDumpKey : @(createAecDump),
     kUseLevelControllerKey : @(useLevelController),
     kUseManualAudioConfigKey : @(useManualAudioConfig)
   } mutableCopy];
+
+  if (videoResolution) {
+    defaultsDictionary[kVideoResolutionKey] = videoResolution;
+  }
+  if (videoCodec) {
+    defaultsDictionary[kVideoCodecKey] = videoCodec;
+  }
   if (bitrate) {
-    [defaultsDictionary setObject:bitrate forKey:kBitrateKey];
+    defaultsDictionary[kBitrateKey] = bitrate;
   }
   [[NSUserDefaults standardUserDefaults] registerDefaults:defaultsDictionary];
 }