From 1bcf8577a4b69428240d0491a604f60167bd5572 Mon Sep 17 00:00:00 2001
From: Christian Brevik <christian.brevik@gmail.com>
Date: Sun, 27 Aug 2017 14:45:47 +0200
Subject: [PATCH 1/2] Add start/stopPreview for Camera

---
 README.md                                     |  8 +++++++
 .../RCTCamera/RCTCameraModule.java            | 12 ++++++++++
 index.js                                      | 22 +++++++++++++++++++
 ios/RCTCameraManager.m                        | 22 +++++++++++++++++++
 4 files changed, 64 insertions(+)

diff --git a/README.md b/README.md
index e4e7d09..f780c52 100644
--- a/README.md
+++ b/README.md
@@ -346,6 +346,14 @@ Returns whether or not the camera has flash capabilities.
 
 Ends the current capture session for video captures. Only applies when the current `captureMode` is `video`.
 
+#### `stopPreview()`
+
+Stops the camera preview from running, and natively will make the current capture session pause.
+
+#### `startPreview()`
+
+Starts the camera preview again if previously stopped.
+
 ## Component static methods
 
 #### `iOS` `Camera.checkDeviceAuthorizationStatus(): Promise`
diff --git a/android/src/main/java/com/lwansbrough/RCTCamera/RCTCameraModule.java b/android/src/main/java/com/lwansbrough/RCTCamera/RCTCameraModule.java
index 10b59f9..1089273 100644
--- a/android/src/main/java/com/lwansbrough/RCTCamera/RCTCameraModule.java
+++ b/android/src/main/java/com/lwansbrough/RCTCamera/RCTCameraModule.java
@@ -658,6 +658,18 @@ public class RCTCameraModule extends ReactContextBaseJavaModule
         }
     }
 
+    @ReactMethod
+    public void stopPreview(ReadableMap options) {
+        Camera camera = RCTCamera.getInstance().acquireCameraInstance(options.getInt("type"));
+        camera.stopPreview();
+    }
+
+    @ReactMethod
+    public void startPreview(ReadableMap options) {
+        Camera camera = RCTCamera.getInstance().acquireCameraInstance(options.getInt("type"));
+        camera.startPreview();
+    }
+
     @ReactMethod
     public void hasFlash(ReadableMap options, final Promise promise) {
         Camera camera = RCTCamera.getInstance().acquireCameraInstance(options.getInt("type"));
diff --git a/index.js b/index.js
index f1957e9..8e1d059 100644
--- a/index.js
+++ b/index.js
@@ -236,6 +236,28 @@ export default class Camera extends Component {
     return CameraManager.capture(options);
   }
 
+  startPreview() {
+    if (Platform.OS === 'android') {
+      const props = convertNativeProps(this.props);
+      CameraManager.startPreview({
+        type: props.type
+      });
+    } else {
+      CameraManager.startPreview();
+    }
+  }
+
+  stopPreview() {
+    if (Platform.OS === 'android') {
+      const props = convertNativeProps(this.props);
+      CameraManager.stopPreview({
+        type: props.type
+      });
+    } else {
+      CameraManager.stopPreview();
+    }
+  }
+
   stopCapture() {
     if (this.state.isRecording) {
       this.setState({ isRecording: false });
diff --git a/ios/RCTCameraManager.m b/ios/RCTCameraManager.m
index 2310080..ea6d355 100644
--- a/ios/RCTCameraManager.m
+++ b/ios/RCTCameraManager.m
@@ -374,6 +374,28 @@ RCT_EXPORT_METHOD(capture:(NSDictionary *)options
   }
 }
 
+RCT_EXPORT_METHOD(stopPreview) {
+#if TARGET_IPHONE_SIMULATOR
+    return;
+#endif
+    dispatch_async(self.sessionQueue, ^{
+        if ([self.session isRunning]) {
+            [self.session stopRunning];
+        }
+    });
+}
+
+RCT_EXPORT_METHOD(startPreview) {
+#if TARGET_IPHONE_SIMULATOR
+    return;
+#endif
+    dispatch_async(self.sessionQueue, ^{
+        if (![self.session isRunning]) {
+            [self.session startRunning];
+        }
+    });
+}
+
 RCT_EXPORT_METHOD(stopCapture) {
   if (self.movieFileOutput.recording) {
     [self.movieFileOutput stopRecording];

From 4e04e3484b272e0bb3486907a21c9d46947ab7c9 Mon Sep 17 00:00:00 2001
From: Christian Brevik <christian.brevik@gmail.com>
Date: Tue, 29 Aug 2017 14:35:35 +0200
Subject: [PATCH 2/2] Make safer calls on Android

---
 .../com/lwansbrough/RCTCamera/RCTCameraModule.java | 14 ++++++++++++--
 1 file changed, 12 insertions(+), 2 deletions(-)

diff --git a/android/src/main/java/com/lwansbrough/RCTCamera/RCTCameraModule.java b/android/src/main/java/com/lwansbrough/RCTCamera/RCTCameraModule.java
index 1089273..fe88bf1 100644
--- a/android/src/main/java/com/lwansbrough/RCTCamera/RCTCameraModule.java
+++ b/android/src/main/java/com/lwansbrough/RCTCamera/RCTCameraModule.java
@@ -660,13 +660,23 @@ public class RCTCameraModule extends ReactContextBaseJavaModule
 
     @ReactMethod
     public void stopPreview(ReadableMap options) {
-        Camera camera = RCTCamera.getInstance().acquireCameraInstance(options.getInt("type"));
+        RCTCamera instance = RCTCamera.getInstance();
+        if (instance == null) return;
+
+        Camera camera = instance.acquireCameraInstance(options.getInt("type"));
+        if (camera == null) return;
+
         camera.stopPreview();
     }
 
     @ReactMethod
     public void startPreview(ReadableMap options) {
-        Camera camera = RCTCamera.getInstance().acquireCameraInstance(options.getInt("type"));
+        RCTCamera instance = RCTCamera.getInstance();
+        if (instance == null) return;
+
+        Camera camera = instance.acquireCameraInstance(options.getInt("type"));
+        if (camera == null) return;
+
         camera.startPreview();
     }