[CameraRoll] support fetching videos from the camera roll

Summary:
This adds a parameter for fetching videos from the camera roll. It also changes the default to fetch both videos and photos.
Closes https://github.com/facebook/react-native/pull/774
Github Author: Joshua Sierles <joshua@diluvia.net>

Test Plan: Imported from GitHub, without a `Test Plan:` line.

Examples/UIExplorer/CameraRollView.ios.js

@@ -59,6 +59,16 @@ var propTypes = {
    * imagesPerRow: Number of images to be shown in each row.
    */
   imagesPerRow: React.PropTypes.number,
+
+   /**
+   * The asset type, one of 'Photos', 'Videos' or 'All'
+   */
+  assetType: React.PropTypes.oneOf([
+    'Photos',
+    'Videos',
+    'All',
+  ]),
+
 };
 
 var CameraRollView = React.createClass({
@@ -69,6 +79,7 @@ var CameraRollView = React.createClass({
       groupTypes: 'SavedPhotos',
       batchSize: 5,
       imagesPerRow: 1,
+      assetType: 'Photos',
       renderImage: function(asset) {
         var imageSize = 150;
         var imageStyle = [styles.image, {width: imageSize, height: imageSize}];
@@ -89,6 +100,7 @@ var CameraRollView = React.createClass({
       assets: ([]: Array<Image>),
       groupTypes: this.props.groupTypes,
       lastCursor: (null : ?string),
+      assetType: this.props.assetType,
       noMore: false,
       loadingMore: false,
       dataSource: ds,
@@ -124,7 +136,8 @@ var CameraRollView = React.createClass({
 
     var fetchParams: Object = {
       first: this.props.batchSize,
-      groupTypes: this.props.groupTypes
+      groupTypes: this.props.groupTypes,
+      assetType: this.props.assetType,
     };
     if (this.state.lastCursor) {
       fetchParams.after = this.state.lastCursor;

Libraries/CameraRoll/CameraRoll.js

@@ -29,8 +29,16 @@ var GROUP_TYPES_OPTIONS = [
   'SavedPhotos', // default
 ];
 
+var ASSET_TYPE_OPTIONS = [
+  'All',
+  'Videos',
+  'Photos', // default
+];
+
+
 // Flow treats Object and Array as disjoint types, currently.
 deepFreezeAndThrowOnMutationInDev((GROUP_TYPES_OPTIONS: any));
+deepFreezeAndThrowOnMutationInDev((ASSET_TYPE_OPTIONS: any));
 
 /**
  * Shape of the param arg for the `getPhotos` function.
@@ -58,6 +66,11 @@ var getPhotosParamChecker = createStrictShapeTypeChecker({
    * titles.
    */
   groupName: ReactPropTypes.string,
+
+  /**
+  * Specifies filter on asset type
+  */
+  assetType: ReactPropTypes.oneOf(ASSET_TYPE_OPTIONS),
 });
 
 /**
@@ -94,6 +107,7 @@ var getPhotosReturnChecker = createStrictShapeTypeChecker({
 class CameraRoll {
 
   static GroupTypesOptions: Array<string>;
+  static AssetTypeOptions: Array<string>;
   /**
    * Saves the image with tag `tag` to the camera roll.
    *
@@ -154,5 +168,6 @@ class CameraRoll {
 }
 
 CameraRoll.GroupTypesOptions = GROUP_TYPES_OPTIONS;
+CameraRoll.AssetTypeOptions = ASSET_TYPE_OPTIONS;
 
 module.exports = CameraRoll;

Libraries/Image/RCTCameraRollManager.m

@@ -69,7 +69,9 @@ RCT_EXPORT_METHOD(getPhotos:(NSDictionary *)params
   NSString *afterCursor = params[@"after"];
   NSString *groupTypesStr = params[@"groupTypes"];
   NSString *groupName = params[@"groupName"];
+  NSString *assetType = params[@"assetType"];
   ALAssetsGroupType groupTypes;
+
   if ([groupTypesStr isEqualToString:@"Album"]) {
     groupTypes = ALAssetsGroupAlbum;
   } else if ([groupTypesStr isEqualToString:@"All"]) {
@@ -93,7 +95,15 @@ RCT_EXPORT_METHOD(getPhotos:(NSDictionary *)params
 
   [[RCTImageLoader assetsLibrary] enumerateGroupsWithTypes:groupTypes usingBlock:^(ALAssetsGroup *group, BOOL *stopGroups) {
     if (group && (groupName == nil || [groupName isEqualToString:[group valueForProperty:ALAssetsGroupPropertyName]])) {
+
+      if (assetType == nil || [assetType isEqualToString:@"Photos"]) {
         [group setAssetsFilter:ALAssetsFilter.allPhotos];
+      } else if ([assetType isEqualToString:@"Videos"]) {
+        [group setAssetsFilter:ALAssetsFilter.allVideos];
+      } else if ([assetType isEqualToString:@"All"]) {
+        [group setAssetsFilter:ALAssetsFilter.allAssets];
+      }
+
       [group enumerateAssetsWithOptions:NSEnumerationReverse usingBlock:^(ALAsset *result, NSUInteger index, BOOL *stopAssets) {
         if (result) {
           NSString *uri = [(NSURL *)[result valueForProperty:ALAssetPropertyAssetURL] absoluteString];