Add setting to AppRTCMobile for iOS, that can change capture resolution.
To achieve this, several changes needed to be made on both UI and
app logic level.
* Settings view controller is added (modally shown when the settings
button is pressed).
- From there the user can see the current capture resolution
and select another capture resolution.
* Model class for the capture resolution added.
- Improves readability and makes separation of concerns cleaner
- Handles persisting
- Provides defaults
- Maps video resolution setting to RTCMediaConstraints dictionary
* Test for the model class
In future it would be possible to extend this CL and add further settings (i.e
bit rate).
Also it would be easy to remove the hardcoded resolutions and use dynamic values
depending on device capability.
BUG=webrtc:6473
Review-Url: https://codereview.webrtc.org/2462623002
Cr-Commit-Position: refs/heads/master@{#14881}
diff --git a/webrtc/examples/objc/AppRTCMobile/ios/ARDMediaConstraintsModel.h b/webrtc/examples/objc/AppRTCMobile/ios/ARDMediaConstraintsModel.h
new file mode 100644
index 0000000..2f963e0
--- /dev/null
+++ b/webrtc/examples/objc/AppRTCMobile/ios/ARDMediaConstraintsModel.h
@@ -0,0 +1,60 @@
+/*
+ * Copyright 2016 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>
+
+NS_ASSUME_NONNULL_BEGIN
+/**
+ * Model class for user defined media constraints.
+ *
+ * Currently used for streaming media constraints only.
+ * In future audio media constraints support can be added as well.
+ * Offers list of avaliable video resolutions that can construct streaming media constraint.
+ * Exposes methods for reading and storing media constraints from persistent store.
+ * Also translates current user defined media constraint into RTCMediaConstraints
+ * dictionary.
+ */
+@interface ARDMediaConstraintsModel : NSObject
+
+/**
+ * Returns array of available capture resoultions.
+ *
+ * The capture resolutions are represented as strings in the following format
+ * [width]x[height]
+ */
+- (NSArray<NSString *> *)availableVideoResoultionsMediaConstraints;
+
+/**
+ * Returns current video resolution media constraint string.
+ * If no constraint is in store, default value of 640x480 is returned.
+ * When defaulting to value, the default is saved in store for consistency reasons.
+ */
+- (NSString *)currentVideoResoultionConstraintFromStore;
+
+/**
+ * Stores the provided video resolution media constraint string into the store.
+ *
+ * If the provided constraint is no part of the available video resolutions
+ * the store operation will not be executed and NO will be returned.
+ * @param constraint the string to be stored.
+ * @return YES/NO depending on success.
+ */
+- (BOOL)storeVideoResoultionConstraint:(NSString *)constraint;
+
+/**
+ * Converts the current media constraints from store into dictionary with RTCMediaConstraints
+ * values.
+ *
+ * @return NSDictionary with RTC width and height parameters
+ */
+- (nullable NSDictionary *)currentMediaConstraintFromStoreAsRTCDictionary;
+
+@end
+NS_ASSUME_NONNULL_END