add keepAwake prop

Camera.js

@@ -67,6 +67,7 @@ export default class Camera extends Component {
       PropTypes.string,
       PropTypes.number
     ]),
+    keepAwake: PropTypes.bool,
     onBarCodeRead: PropTypes.func,
     onFocusChanged: PropTypes.func,
     onZoomChanged: PropTypes.func,

README.md

@@ -211,6 +211,10 @@ If `defaultOnFocusComponent` set to false, default internal implementation of vi
 Called when focus has changed.
 By default, `onZoomChanged` is not defined and pinch-to-zoom is disabled.
 
+#### `iOS` `keepAwake`
+
+If set to `true`, the device will not sleep while the camera preview is visible. This mimics the behavior of the default camera app, which keeps the device awake while open.
+
 ## Component instance methods
 
 You can access component methods by adding a `ref` (ie. `ref="camera"`) prop to your `<Camera>` element, then you can use `this.refs.camera.capture(cb)`, etc. inside your component.

ios/RCTCamera.m

@@ -16,6 +16,7 @@
   BOOL _onFocusChanged;
   BOOL _defaultOnFocusComponent;
   BOOL _onZoomChanged;
+  BOOL _previousIdleTimerDisabled;
 }
 
 - (void)setAspect:(NSInteger)aspect
@@ -90,6 +91,13 @@
   }
 }
 
+- (void)setKeepAwake:(BOOL)enabled
+{
+  if (enabled) {
+    [UIApplication sharedApplication].idleTimerDisabled = true;
+  }
+}
+
 - (id)initWithManager:(RCTCameraManager*)manager bridge:(RCTBridge *)bridge
 {
   
@@ -104,6 +112,7 @@
     _onFocusChanged = NO;
     _defaultOnFocusComponent = YES;
     _onZoomChanged = NO;
+    _previousIdleTimerDisabled = [UIApplication sharedApplication].idleTimerDisabled;
   }
   return self;
 }
@@ -133,6 +142,7 @@
   [self.manager stopSession];
   [super removeFromSuperview];
   [[NSNotificationCenter defaultCenter] removeObserver:self name:UIDeviceOrientationDidChangeNotification object:nil];
+  [UIApplication sharedApplication].idleTimerDisabled = _previousIdleTimerDisabled;
 }
 
 - (void)orientationChanged:(NSNotification *)notification{

ios/RCTCameraManager.m

@@ -30,6 +30,7 @@ RCT_EXPORT_VIEW_PROPERTY(type, NSInteger);
 RCT_EXPORT_VIEW_PROPERTY(orientation, NSInteger);
 RCT_EXPORT_VIEW_PROPERTY(flashMode, NSInteger);
 RCT_EXPORT_VIEW_PROPERTY(torchMode, NSInteger);
+RCT_EXPORT_VIEW_PROPERTY(keepAwake, BOOL);
 
 - (NSDictionary *)constantsToExport
 {