[WEEX-215][iOS] recycle-list scroll orientation support

ios/sdk/WeexSDK/Sources/Component/RecycleList/WXRecycleListComponent.m

@@ -48,6 +48,7 @@ @implementation WXRecycleListComponent
     NSMutableDictionary *_stickyCache;
 
     NSUInteger _previousLoadMoreCellNumber;
+    WXScrollDirection _scrollDirection;
 }
 
 WX_EXPORT_METHOD(@selector(appendData:))
@@ -77,6 +78,7 @@ - (instancetype)initWithRef:(NSString *)ref
         _indexKey = [WXConvert NSString:attributes[@"index"]];
         _sizeCache = [NSMutableDictionary dictionary];
         _stickyCache = [NSMutableDictionary dictionary];
+        _scrollDirection = attributes[@"scrollDirection"] ? [WXConvert WXScrollDirection:attributes[@"scrollDirection"]] : WXScrollDirectionVertical;
     }
 
     return self;
@@ -86,11 +88,7 @@ - (instancetype)initWithRef:(NSString *)ref
 
 - (UIView *)loadView
 {
-    WXRecycleListLayout *layout = [WXRecycleListLayout new];
-    layout.delegate = self;
-    // to show cells that original width / height is zero, otherwise cellForItemAtIndexPath will not be called
-    layout.minimumLineSpacing = 0.01;
-    layout.minimumInteritemSpacing = 0.01;
+    WXRecycleListLayout *layout = [self recycleListLayout];
     return [[UICollectionView alloc] initWithFrame:CGRectZero collectionViewLayout:layout];
 }
 
@@ -131,6 +129,10 @@ - (void)updateAttributes:(NSDictionary *)attributes
     if (attributes[@"index"]) {
         _indexKey = [WXConvert NSString:attributes[@"index"]];
     }
+    if (attributes[@"scrollDirection"]) {
+        WXScrollDirection newScrollDirection = attributes[@"scrollDirection"] ? [WXConvert WXScrollDirection:attributes[@"scrollDirection"]] : WXScrollDirectionVertical;
+        [self _updateScrollDirection:newScrollDirection];
+    }
 }
 
 - (CGPoint)absolutePositionForComponent:(WXComponent *)component
@@ -444,6 +446,29 @@ - (void)_updateListData:(NSArray *)newData
     [_updateManager updateWithNewData:newData oldData:oldData completion:completion animation:animation];
 }
 
+- (void)_updateScrollDirection:(WXScrollDirection)newScrollDirection
+{
+    if (_scrollDirection == newScrollDirection) {
+        return;
+    }
+    _scrollDirection = newScrollDirection;
+    WXRecycleListLayout *layout = [self recycleListLayout];
+    _collectionView.collectionViewLayout = layout;
+}
+
+- (WXRecycleListLayout *)recycleListLayout
+{
+    WXRecycleListLayout *layout = [WXRecycleListLayout new];
+    layout.delegate = self;
+    // to show cells that original width / height is zero, otherwise cellForItemAtIndexPath will not be called
+    layout.minimumLineSpacing = 0.01;
+    layout.minimumInteritemSpacing = 0.01;
+    if (_scrollDirection == WXScrollDirectionHorizontal) {
+        layout.scrollDirection = UICollectionViewScrollDirectionHorizontal;
+    }
+    return layout;
+}
+
 #pragma mark - UICollectionViewDataSource
 
 - (NSInteger)numberOfSectionsInCollectionView:(UICollectionView *)collectionView