Suggestions UI - expandable item

ios/chrome/browser/ui/suggestions/suggestions_expandable_item.h

+// Copyright 2017 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef IOS_CHROME_BROWSER_UI_SUGGESTIONS_SUGGESTIONS_EXPANDABLE_ITEM_H_
+#define IOS_CHROME_BROWSER_UI_SUGGESTIONS_SUGGESTIONS_EXPANDABLE_ITEM_H_
+
+#import "ios/third_party/material_components_ios/src/components/CollectionCells/src/MaterialCollectionCells.h"
+
+#import "ios/chrome/browser/ui/collection_view/cells/collection_view_item.h"
+
+@class SuggestionsExpandableCell;
+
+// Delegate for the SuggestionsExpandableCell. The delegate will take care of
+// the expansion/retractation of the cell.

[marq (ping after 24h), 2017/01/16 17:16:41]

Perfer 'collapse' as the opposite to 'expand' instead of 'retract' ('retract'
usually applies to something long and narrow, like a rope or a telescoping rod).

[gambard, 2017/01/17 09:59:00]

Done.

+@protocol SuggestionsExpandableCellDelegate
+
+- (void)expandCell:(UICollectionViewCell*)cell;
+- (void)retractCell:(UICollectionViewCell*)cell;
+
+@end
+
+// Item for an expandable article in the suggestions. An expandable article can
+// be expanded, displaying more informations/interactions.
+@interface SuggestionsExpandableItem : CollectionViewItem
+
+// Init the article with a |title|, a |subtitle| an |image| and some |detail|
+// displayed only when the article is expanded. |type| is the type of the item.

[marq (ping after 24h), 2017/01/16 17:16:41]

Does |type| vary orthogonally to the expandable/non-expandable distinction? Are
all expandable articles of a certain set of types?

[gambard, 2017/01/17 09:59:00]

It is independent. All expandable items can have the same type or different
type.

[lpromero, 2017/01/17 10:38:49]

And in the other direction, the group of expandable items and the group of
non-expandable items don't share types.

+- (instancetype)initWithType:(NSInteger)type
+                       title:(NSString*)title
+                    subtitle:(NSString*)subtitle
+                       image:(UIImage*)image
+                  detailText:(NSString*)detail NS_DESIGNATED_INITIALIZER;
+
+- (instancetype)initWithType:(NSInteger)type NS_UNAVAILABLE;
+
+// Delegate for the configured cells.

[marq (ping after 24h), 2017/01/16 17:16:41]

each CollectionViewItem configures only a single cell, right? So 'cell' rather
than 'cells'.

[gambard, 2017/01/17 09:59:00]

The item configure the cell for displaying on the collection view and the cell
for the sizing.
Nothing on the API states that it would configure only one cell.

+@property(nonatomic, weak) id<SuggestionsExpandableCellDelegate> delegate;
+
+// Whether the cells should be in expanded mode.
+@property(nonatomic) BOOL expanded;
+
+@end
+
+// Corresponding cell of an expandable article.
+@interface SuggestionsExpandableCell : MDCCollectionViewCell
+
+@property(nonatomic, weak) id<SuggestionsExpandableCellDelegate> delegate;
+@property(nonatomic, readonly, strong) UILabel* titleLabel;
+@property(nonatomic, readonly, strong) UILabel* subtitleLabel;
+@property(nonatomic, readonly, strong) UILabel* detailLabel;
+@property(nonatomic, strong) UIImageView* imageView;
+
+- (void)expand;
+- (void)retract;
+
+@end
+
+#endif  // IOS_CHROME_BROWSER_UI_SUGGESTIONS_SUGGESTIONS_EXPANDABLE_ITEM_H_