Suggestions UI - favicon item

ios/chrome/browser/ui/suggestions/suggestions_favicon_item.mm

+// 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.
+
+#import "ios/chrome/browser/ui/suggestions/suggestions_favicon_item.h"
+
+#import <UIKit/UIKit.h>
+
+#include "base/logging.h"
+#import "ios/chrome/browser/ui/suggestions/suggestions_favicon_internal_cell.h"
+#import "ios/chrome/browser/ui/uikit_ui_util.h"
+
+#if !defined(__has_feature) || !__has_feature(objc_arc)
+#error "This file requires ARC support."
+#endif
+
+namespace {
+// Space between two cells in the internal collection view.
+const CGFloat kInternalCellSpacing = 40;
+// Width of the cells in the internal collection view.
+const CGFloat kInternalCellWidth = 70;
+// Height of the cells in the internal collection view.
+const CGFloat kInternalCellHeight = 120;
+// Leading inset of the internal collection view.
+const CGFloat kInternalLeadingSpacing = 16;
+}  // namespace
+
+#pragma mark - SugggestionsFaviconItem
+
+// The item is the data source of the inner collection view.
+@interface SuggestionsFaviconItem ()<UICollectionViewDataSource> {
+  NSMutableArray<NSString*>* _faviconTitles;
+  NSMutableArray<UIImage*>* _faviconImages;
+}
+
+@end
+
+@implementation SuggestionsFaviconItem
+
+@synthesize delegate = _delegate;
+
+- (instancetype)initWithType:(NSInteger)type {
+  self = [super initWithType:type];
+  if (self) {
+    self.cellClass = [SuggestionsFaviconCell class];
+    _faviconTitles = [NSMutableArray array];
+    _faviconImages = [NSMutableArray array];
+  }
+  return self;
+}
+
+- (void)addFavicon:(UIImage*)favicon withTitle:(NSString*)title {
+  [_faviconImages addObject:favicon];
+  [_faviconTitles addObject:title];
+}
+
+#pragma mark - UICollectionViewDataSource
+
+- (UICollectionViewCell*)collectionView:(UICollectionView*)collectionView
+                 cellForItemAtIndexPath:(NSIndexPath*)indexPath {
+  SuggestionsFaviconInternalCell* cell = [collectionView
+      dequeueReusableCellWithReuseIdentifier:[SuggestionsFaviconInternalCell
+                                                 reuseIdentifier]
+                                forIndexPath:indexPath];
+  cell.faviconView.image = [_faviconImages objectAtIndex:indexPath.item];
+  cell.titleLabel.text = [_faviconTitles objectAtIndex:indexPath.item];
+  return cell;
+}
+
+- (NSInteger)collectionView:(UICollectionView*)collectionView
+     numberOfItemsInSection:(NSInteger)section {
+  DCHECK([_faviconImages count] == [_faviconTitles count]);
+  return [_faviconImages count];
+}
+
+#pragma mark - CollectionViewItem
+
+- (void)configureCell:(SuggestionsFaviconCell*)cell {
+  [super configureCell:cell];
+  cell.collectionView.dataSource = self;
+  cell.delegate = self.delegate;
+}
+
+@end
+
+#pragma mark - SuggestionsFaviconCell
+
+// The cell is the delegate of the inner collection view.
+@interface SuggestionsFaviconCell ()<UICollectionViewDelegate>
+
+@end
+
+@implementation SuggestionsFaviconCell
+
+@synthesize collectionView = _collectionView;
+@synthesize delegate = _delegate;
+
+- (instancetype)initWithFrame:(CGRect)frame {
+  self = [super initWithFrame:frame];
+  if (self) {
+    UICollectionViewFlowLayout* layout =
+        [[UICollectionViewFlowLayout alloc] init];
+    layout.scrollDirection = UICollectionViewScrollDirectionHorizontal;
+    layout.minimumInteritemSpacing = kInternalCellSpacing;
+    layout.itemSize = CGSizeMake(kInternalCellWidth, kInternalCellHeight);
+    layout.sectionInset = UIEdgeInsetsMake(0, kInternalLeadingSpacing, 0, 0);
+
+    _collectionView = [[UICollectionView alloc] initWithFrame:CGRectZero
+                                         collectionViewLayout:layout];
+    [_collectionView registerClass:[SuggestionsFaviconInternalCell class]
+        forCellWithReuseIdentifier:[SuggestionsFaviconInternalCell
+                                       reuseIdentifier]];
+    _collectionView.backgroundColor = [UIColor clearColor];
+    _collectionView.translatesAutoresizingMaskIntoConstraints = NO;
+
+    _collectionView.delegate = self;
+
+    [self.contentView addSubview:_collectionView];
+    AddSameSizeConstraint(_collectionView, self.contentView);
+    [_collectionView.heightAnchor constraintEqualToConstant:kInternalCellHeight]
+        .active = YES;
+  }
+  return self;
+}
+
+- (void)prepareForReuse {
+  [super prepareForReuse];
+  self.collectionView.dataSource = nil;
+  self.delegate = nil;
+}
+
+#pragma mark - UICollectionViewDelegate
+
+- (void)collectionView:(UICollectionView*)collectionView
+    didSelectItemAtIndexPath:(NSIndexPath*)indexPath {
+  [self.delegate openFaviconAtIndexPath:indexPath];
+}
+
+@end