Added iOS support for controlling system flash

Added iOS support for controlling system flash with configurable
brightness

Author: stepanvotava

index.js

@@ -45,6 +45,17 @@ class InCallManager {
         _InCallManager.turnScreenOn();
     }
 
+    setFlashOn(enable, brightness) {
+        if (Platform.OS === 'ios') {
+            enable = (enable === true) ? true : false;
+            brightness = (typeof brightness === 'number') ? brightness : 0;
+            _InCallManager.setFlashOn(enable, brightness);
+        } else {
+            console.log("Android doesn't support setFlashOn(enable, brightness)");
+        }
+    }
+
+
     setKeepScreenOn(enable) {
         enable = (enable === true) ? true : false;
         _InCallManager.setKeepScreenOn(enable);

ios/RNInCallManager/RNInCallManager.swift

@@ -56,6 +56,8 @@ class RNInCallManager: NSObject, AVAudioPlayerDelegate {
     var cameraPermission: String!
     var media: String = "audio"
 
+    private lazy var device: AVCaptureDevice? = { AVCaptureDevice.defaultDeviceWithMediaType(AVMediaTypeVideo) }()
+
     // --- AVAudioSessionCategoryOptionAllowBluetooth:
     // --- Valid only if the audio session category is AVAudioSessionCategoryPlayAndRecord or AVAudioSessionCategoryRecord.
     // --- Using VoiceChat/VideoChat mode has the side effect of enabling the AVAudioSessionCategoryOptionAllowBluetooth category option. 
@@ -250,6 +252,24 @@ class RNInCallManager: NSObject, AVAudioPlayerDelegate {
         }
     }
 
+    @objc func setFlashOn(enable: Bool, brightness: NSNumber) -> Void {
+        guard let device = device else { return }
+        if device.hasTorch && device.position == AVCaptureDevicePosition.Back {
+            do {
+                try device.lockForConfiguration()
+                if enable {
+                    try device.setTorchModeOnWithLevel(brightness.floatValue)
+                } else {
+                    device.torchMode = .Off
+                }
+                NSLog("RNInCallManager.setForceSpeakerphoneOn(): enable: \(enable)")
+                device.unlockForConfiguration()
+            } catch let error {
+                NSLog("RNInCallManager.setFlashOn error != \(error)")
+            }
+        }
+    }
+
     @objc func setKeepScreenOn(_ enable: Bool) -> Void {
         NSLog("RNInCallManager.setKeepScreenOn(): enable: \(enable)")
         UIApplication.shared.isIdleTimerDisabled = enable

ios/RNInCallManager/RNInCallManagerBridge.m

@@ -13,6 +13,7 @@ @interface RCT_EXTERN_REMAP_MODULE(InCallManager, RNInCallManager, NSObject)
 RCT_EXTERN_METHOD(stop:(NSString *)busytone)
 RCT_EXTERN_METHOD(turnScreenOn)
 RCT_EXTERN_METHOD(turnScreenOff)
+RCT_EXTERN_METHOD(setFlashOn:(BOOL)enable brightness:(nonnull NSNumber *)brightness)
 RCT_EXTERN_METHOD(setKeepScreenOn:(BOOL)enable)
 RCT_EXTERN_METHOD(setSpeakerphoneOn:(BOOL)enable)
 RCT_EXTERN_METHOD(setForceSpeakerphoneOn:(int)flag)