Add new view that renders local video using AVCaptureLayerPreview.
BUG=
Review URL: https://codereview.webrtc.org/1497393002
Cr-Commit-Position: refs/heads/master@{#10940}
diff --git a/webrtc/base/objc/RTCCameraPreviewView.h b/webrtc/base/objc/RTCCameraPreviewView.h
new file mode 100644
index 0000000..03e94c2
--- /dev/null
+++ b/webrtc/base/objc/RTCCameraPreviewView.h
@@ -0,0 +1,28 @@
+/*
+ * Copyright 2015 The WebRTC Project Authors. All rights reserved.
+ *
+ * Use of this source code is governed by a BSD-style license
+ * that can be found in the LICENSE file in the root of the source
+ * tree. An additional intellectual property rights grant can be found
+ * in the file PATENTS. All contributing project authors may
+ * be found in the AUTHORS file in the root of the source tree.
+ */
+
+#import <Foundation/Foundation.h>
+#import <UIKit/UIKit.h>
+
+@class AVCaptureSession;
+@class RTCAVFoundationVideoSource;
+
+/** RTCCameraPreviewView is a view that renders local video from an
+ * AVCaptureSession.
+ */
+@interface RTCCameraPreviewView : UIView
+
+/** The capture session being rendered in the view. Capture session
+ * is assigned to AVCaptureVideoPreviewLayer async in the same
+ * queue that the AVCaptureSession is started/stopped.
+ */
+@property(nonatomic, strong) AVCaptureSession *captureSession;
+
+@end
diff --git a/webrtc/base/objc/RTCCameraPreviewView.m b/webrtc/base/objc/RTCCameraPreviewView.m
new file mode 100644
index 0000000..5a57483
--- /dev/null
+++ b/webrtc/base/objc/RTCCameraPreviewView.m
@@ -0,0 +1,47 @@
+/*
+ * Copyright 2015 The WebRTC Project Authors. All rights reserved.
+ *
+ * Use of this source code is governed by a BSD-style license
+ * that can be found in the LICENSE file in the root of the source
+ * tree. An additional intellectual property rights grant can be found
+ * in the file PATENTS. All contributing project authors may
+ * be found in the AUTHORS file in the root of the source tree.
+ */
+
+#if !defined(__has_feature) || !__has_feature(objc_arc)
+#error "This file requires ARC support."
+#endif
+
+#import "webrtc/base/objc/RTCCameraPreviewView.h"
+
+#import <AVFoundation/AVFoundation.h>
+
+#import "webrtc/base/objc/RTCDispatcher.h"
+
+@implementation RTCCameraPreviewView
+
+@synthesize captureSession = _captureSession;
+
++ (Class)layerClass {
+ return [AVCaptureVideoPreviewLayer class];
+}
+
+- (void)setCaptureSession:(AVCaptureSession *)captureSession {
+ if (_captureSession == captureSession) {
+ return;
+ }
+ _captureSession = captureSession;
+ AVCaptureVideoPreviewLayer *previewLayer = [self previewLayer];
+ [RTCDispatcher dispatchAsyncOnType:RTCDispatcherTypeCaptureSession
+ block:^{
+ previewLayer.session = captureSession;
+ }];
+}
+
+#pragma mark - Private
+
+- (AVCaptureVideoPreviewLayer *)previewLayer {
+ return (AVCaptureVideoPreviewLayer *)self.layer;
+}
+
+@end
diff --git a/webrtc/base/objc/RTCDispatcher.h b/webrtc/base/objc/RTCDispatcher.h
new file mode 100644
index 0000000..c32b93d
--- /dev/null
+++ b/webrtc/base/objc/RTCDispatcher.h
@@ -0,0 +1,35 @@
+/*
+ * Copyright 2015 The WebRTC project authors. All Rights Reserved.
+ *
+ * Use of this source code is governed by a BSD-style license
+ * that can be found in the LICENSE file in the root of the source
+ * tree. An additional intellectual property rights grant can be found
+ * in the file PATENTS. All contributing project authors may
+ * be found in the AUTHORS file in the root of the source tree.
+ */
+
+#import <Foundation/Foundation.h>
+
+typedef NS_ENUM(NSInteger, RTCDispatcherQueueType) {
+ // Main dispatcher queue.
+ RTCDispatcherTypeMain,
+ // Used for starting/stopping AVCaptureSession, and assigning
+ // capture session to AVCaptureVideoPreviewLayer.
+ RTCDispatcherTypeCaptureSession,
+};
+
+/** Dispatcher that asynchronously dispatches blocks to a specific
+ * shared dispatch queue.
+ */
+@interface RTCDispatcher : NSObject
+
+- (instancetype)init NS_UNAVAILABLE;
+
+/** Dispatch the block asynchronously on the queue for dispatchType.
+ * @param dispatchType The queue type to dispatch on.
+ * @param block The block to dispatch asynchronously.
+ */
++ (void)dispatchAsyncOnType:(RTCDispatcherQueueType)dispatchType
+ block:(dispatch_block_t)block;
+
+@end
diff --git a/webrtc/base/objc/RTCDispatcher.m b/webrtc/base/objc/RTCDispatcher.m
new file mode 100644
index 0000000..065705a
--- /dev/null
+++ b/webrtc/base/objc/RTCDispatcher.m
@@ -0,0 +1,46 @@
+/*
+ * Copyright 2015 The WebRTC project authors. All Rights Reserved.
+ *
+ * Use of this source code is governed by a BSD-style license
+ * that can be found in the LICENSE file in the root of the source
+ * tree. An additional intellectual property rights grant can be found
+ * in the file PATENTS. All contributing project authors may
+ * be found in the AUTHORS file in the root of the source tree.
+ */
+
+#import "RTCDispatcher.h"
+
+static dispatch_queue_t kCaptureSessionQueue = nil;
+
+@implementation RTCDispatcher {
+ dispatch_queue_t _captureSessionQueue;
+}
+
++ (void)initialize {
+ static dispatch_once_t onceToken;
+ dispatch_once(&onceToken, ^{
+ kCaptureSessionQueue = dispatch_queue_create(
+ "org.webrtc.RTCDispatcherCaptureSession",
+ DISPATCH_QUEUE_SERIAL);
+ });
+}
+
++ (void)dispatchAsyncOnType:(RTCDispatcherQueueType)dispatchType
+ block:(dispatch_block_t)block {
+ dispatch_queue_t queue = [self dispatchQueueForType:dispatchType];
+ dispatch_async(queue, block);
+}
+
+#pragma mark - Private
+
++ (dispatch_queue_t)dispatchQueueForType:(RTCDispatcherQueueType)dispatchType {
+ switch (dispatchType) {
+ case RTCDispatcherTypeMain:
+ return dispatch_get_main_queue();
+ case RTCDispatcherTypeCaptureSession:
+ return kCaptureSessionQueue;
+ }
+}
+
+@end
+