feat(iOS): allow for audio session to be kept (react-native-camera#2636)

* allow for audio session to be kept even after unmounts

* readme typo

docs/RNCamera.md

@@ -230,6 +230,12 @@ Values: boolean `true` (default) | `false`
 Specifies if audio recording permissions should be requested.
 Make sure to follow README instructions for audio recording permissions [here](README.md).
 
+### iOS `keepAudioSession`
+
+Values: boolean `true` | `false` (false)
+
+(iOS Only) When the camera is unmounted, it will release any audio session it acquired (if `captureAudio=true`) so other media can continue playing. However, this might not be always desirable (e.g., if video is played afterwards) and can be disabled by setting it to `true`. Setting this to `true`, means your app will not release the audio session. Note: other apps might still "steal" the audio session from your app.
+
 ### `flashMode`
 
 Values: `RNCamera.Constants.FlashMode.off` (default), `RNCamera.Constants.FlashMode.on`, `RNCamera.Constants.FlashMode.auto` or `RNCamera.Constants.FlashMode.torch`.
@@ -698,7 +704,7 @@ A rewritten version of `react-native-barcode-mask` using `Hooks` and `Reanimated
 - Customizable
 - Provide custom hook to "scan barcode within finder area"
 
-Read more about it here [@nartc/react-native-barcode-mask](https://github.com/nartc/react-native-barcode-mask) 
+Read more about it here [@nartc/react-native-barcode-mask](https://github.com/nartc/react-native-barcode-mask)
 
 ## Testing
 

ios/RN/RNCamera.h

@@ -46,6 +46,7 @@
 @property(nonatomic, assign) BOOL canDetectFaces;
 @property(nonatomic, assign) BOOL canDetectBarcodes;
 @property(nonatomic, assign) BOOL captureAudio;
+@property(nonatomic, assign) BOOL keepAudioSession;
 @property(nonatomic, assign) CGRect rectOfInterest;
 @property(assign, nonatomic) AVVideoCodecType videoCodecType;
 @property(assign, nonatomic)

ios/RN/RNCamera.m

@@ -1342,19 +1342,22 @@ - (void)removeAudioCaptureSessionInput
 
         // Deactivate our audio session so other audio can resume
         // playing, if any. E.g., background music.
-        NSError *error = nil;
+        // unless told not to
+        if(!self.keepAudioSession){
+            NSError *error = nil;
 
-        BOOL setInactive = [[AVAudioSession sharedInstance] setActive:NO withOptions:AVAudioSessionSetActiveOptionNotifyOthersOnDeactivation error:&error];
+            BOOL setInactive = [[AVAudioSession sharedInstance] setActive:NO withOptions:AVAudioSessionSetActiveOptionNotifyOthersOnDeactivation error:&error];
 
-        if (!setInactive) {
-            RCTLogWarn(@"Audio device could not set inactive: %s: %@", __func__, error);
+            if (!setInactive) {
+                RCTLogWarn(@"Audio device could not set inactive: %s: %@", __func__, error);
+            }
         }
-
+        
         self.audioCaptureDeviceInput = nil;
 
         // inform that audio was interrupted
         if(audioRemoved && self.onAudioInterrupted){
-           self.onAudioInterrupted(nil);
+            self.onAudioInterrupted(nil);
         }
     }
 }

ios/RN/RNCameraManager.m

@@ -305,6 +305,11 @@ + (NSDictionary *)barcodeDetectorConstants
     [view updateCaptureAudio];
 }
 
+RCT_CUSTOM_VIEW_PROPERTY(keepAudioSession, BOOL, RNCamera)
+{
+    [view setKeepAudioSession:[RCTConvert BOOL:json]];
+}
+
 RCT_CUSTOM_VIEW_PROPERTY(rectOfInterest, CGRect, RNCamera)
 {
     [view setRectOfInterest: [RCTConvert CGRect:json]];

src/RNCamera.js

@@ -270,6 +270,7 @@ type PropsType = typeof View.props & {
   onFacesDetected?: ({ faces: Array<TrackedFaceFeature> }) => void,
   onTextRecognized?: ({ textBlocks: Array<TrackedTextFeature> }) => void,
   captureAudio?: boolean,
+  keepAudioSession?: boolean,
   useCamera2Api?: boolean,
   playSoundOnCapture?: boolean,
   videoStabilizationMode?: number | string,
@@ -417,6 +418,7 @@ export default class Camera extends React.Component<PropsType, StateType> {
     notAuthorizedView: PropTypes.element,
     pendingAuthorizationView: PropTypes.element,
     captureAudio: PropTypes.bool,
+    keepAudioSession: PropTypes.bool,
     useCamera2Api: PropTypes.bool,
     playSoundOnCapture: PropTypes.bool,
     videoStabilizationMode: PropTypes.oneOfType([PropTypes.string, PropTypes.number]),
@@ -466,6 +468,7 @@ export default class Camera extends React.Component<PropsType, StateType> {
       </View>
     ),
     captureAudio: true,
+    keepAudioSession: false,
     useCamera2Api: false,
     playSoundOnCapture: false,
     pictureSize: 'None',

types/index.d.ts

@@ -223,6 +223,8 @@ export interface RNCameraProps {
 
   // -- IOS ONLY PROPS
   defaultVideoQuality?: keyof VideoQuality;
+  /* if true, audio session will not be released on component unmount */
+  keepAudioSession?: boolean;
 }
 
 interface Point<T = number> {