Selected shipping option in payment summary view + shipping option selection view

ios/chrome/browser/payments/shipping_option_selection_view_controller.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/payments/shipping_option_selection_view_controller.h"
+
+#import "base/ios/weak_nsobject.h"
+#include "base/mac/foundation_util.h"
+#include "base/strings/sys_string_conversions.h"
+#include "components/strings/grit/components_strings.h"
+#import "ios/chrome/browser/payments/payment_request_utils.h"
+#import "ios/chrome/browser/ui/collection_view/cells/collection_view_item.h"
+#import "ios/chrome/browser/ui/collection_view/cells/collection_view_text_item.h"
+#import "ios/chrome/browser/ui/collection_view/collection_view_model.h"
+#import "ios/chrome/browser/ui/icons/chrome_icon.h"
+#include "ios/chrome/grit/ios_strings.h"
+#import "ios/third_party/material_components_ios/src/components/Palettes/src/MaterialPalettes.h"
+#import "ios/third_party/material_components_ios/src/components/Typography/src/MaterialTypography.h"
+#include "ui/base/l10n/l10n_util.h"
+
+NSString* const kShippingOptionSelectionCollectionViewId =
+    @"kShippingOptionSelectionCollectionViewId";
+
+namespace {
+
+const CGFloat kSeparatorEdgeInset = 14;
+
+typedef NS_ENUM(NSInteger, SectionIdentifier) {
+  SectionIdentifierShippingOption = kSectionIdentifierEnumZero,
+};
+
+typedef NS_ENUM(NSInteger, ItemType) {
+  ItemTypeShippingOption = kItemTypeEnumZero,  // This is a repeated item type.
+};
+
+}  // namespace
+
+@interface ShippingOptionSelectionViewController () {
+  base::WeakNSProtocol<id<ShippingOptionSelectionViewControllerDelegate>>
+      _delegate;
+
+  CollectionViewTextItem* _selectedItem;
+}
+
+// Called when the user presses the return button.
+- (void)onReturn;
+
+@end
+
+@implementation ShippingOptionSelectionViewController
+
+@synthesize shippingOptions = _shippingOptions;
+@synthesize selectedShippingOption = _selectedShippingOption;
+
+- (instancetype)init {
+  if ((self = [super initWithStyle:CollectionViewControllerStyleAppBar])) {
+    self.title = l10n_util::GetNSString(
+        IDS_IOS_PAYMENT_REQUEST_SHIPPING_OPTION_SELECTION_TITLE);
+
+    UIBarButtonItem* returnButton =
+        [ChromeIcon templateBarButtonItemWithImage:[ChromeIcon backIcon]
+                                            target:nil
+                                            action:@selector(onReturn)];
+    returnButton.accessibilityLabel = l10n_util::GetNSString(IDS_ACCNAME_BACK);
+    self.navigationItem.leftBarButtonItem = returnButton;
+  }
+  return self;
+}
+
+- (id<ShippingOptionSelectionViewControllerDelegate>)delegate {
+  return _delegate.get();
+}
+
+- (void)setDelegate:
+    (id<ShippingOptionSelectionViewControllerDelegate>)delegate {
+  _delegate.reset(delegate);
+}
+
+- (void)onReturn {
+  [_delegate shippingOptionSelectionViewControllerDidReturn:self];
+}
+
+#pragma mark - CollectionViewController methods
+
+- (void)loadModel {
+  [super loadModel];
+  CollectionViewModel* model = self.collectionViewModel;
+
+  [model addSectionWithIdentifier:SectionIdentifierShippingOption];
+
+  for (size_t i = 0; i < _shippingOptions.size(); ++i) {
+    web::PaymentShippingOption* shippingOption = _shippingOptions[i];
+    CollectionViewTextItem* item = [[[CollectionViewTextItem alloc]
+        initWithType:ItemTypeShippingOption] autorelease];
+    item.text = base::SysUTF16ToNSString(shippingOption->label);
+    NSString* currencyCode =
+        base::SysUTF16ToNSString(shippingOption->amount.currency);
+    NSDecimalNumber* value = [NSDecimalNumber
+        decimalNumberWithString:SysUTF16ToNSString(
+                                    shippingOption->amount.value)];
+    item.detailText =
+        payment_request_utils::FormattedCurrencyString(value, currencyCode);
+
+    if (_selectedShippingOption == shippingOption) {
+      item.accessoryType = MDCCollectionViewCellAccessoryCheckmark;
+      _selectedItem = item;
+    }
+
+    [model addItem:item
+        toSectionWithIdentifier:SectionIdentifierShippingOption];
+  }
+}
+
+- (void)viewDidLoad {
+  [super viewDidLoad];
+  self.collectionView.accessibilityIdentifier =
+      kShippingOptionSelectionCollectionViewId;
+
+  // Customize collection view settings.
+  self.styler.cellStyle = MDCCollectionViewCellStyleCard;
+  self.styler.separatorInset =
+      UIEdgeInsetsMake(0, kSeparatorEdgeInset, 0, kSeparatorEdgeInset);
+}
+
+#pragma mark UICollectionViewDataSource
+
+- (UICollectionViewCell*)collectionView:(UICollectionView*)collectionView
+                 cellForItemAtIndexPath:(nonnull NSIndexPath*)indexPath {
+  UICollectionViewCell* cell =
+      [super collectionView:collectionView cellForItemAtIndexPath:indexPath];
+
+  NSInteger itemType =
+      [self.collectionViewModel itemTypeForIndexPath:indexPath];
+  DCHECK(ItemTypeShippingOption == itemType);
+
+  MDCCollectionViewTextCell* textCell =
+      base::mac::ObjCCastStrict<MDCCollectionViewTextCell>(cell);
+  textCell.textLabel.font = [MDCTypography body2Font];
+  textCell.textLabel.textColor = [[MDCPalette greyPalette] tint900];
+  textCell.detailTextLabel.font = [MDCTypography body1Font];
+  textCell.detailTextLabel.textColor = [[MDCPalette greyPalette] tint900];
+
+  return cell;
+}
+
+#pragma mark UICollectionViewDelegate
+
+- (void)collectionView:(UICollectionView*)collectionView
+    didSelectItemAtIndexPath:(NSIndexPath*)indexPath {
+  [super collectionView:collectionView didSelectItemAtIndexPath:indexPath];
+
+  CollectionViewModel* model = self.collectionViewModel;
+
+  NSInteger itemType =
+      [self.collectionViewModel itemTypeForIndexPath:indexPath];
+  DCHECK(ItemTypeShippingOption == itemType);
+
+  NSIndexPath* currentlySelectedIndexPath = [self.collectionViewModel
+             indexPathForItem:_selectedItem
+      inSectionWithIdentifier:SectionIdentifierShippingOption];
+  if (currentlySelectedIndexPath != indexPath) {
+    // Update the cells.
+    CollectionViewItem* item = [model itemAtIndexPath:indexPath];
+    CollectionViewTextItem* newlySelectedItem =
+        base::mac::ObjCCastStrict<CollectionViewTextItem>(item);
+    newlySelectedItem.accessoryType = MDCCollectionViewCellAccessoryCheckmark;
+
+    _selectedItem.accessoryType = MDCCollectionViewCellAccessoryNone;
+
+    [self reconfigureCellsForItems:@[ _selectedItem, newlySelectedItem ]
+           inSectionWithIdentifier:SectionIdentifierShippingOption];
+
+    // Update the selected shipping option and its respective item.
+    NSInteger index = [model indexInItemTypeForIndexPath:indexPath];
+    DCHECK(index < (NSInteger)_shippingOptions.size());
+    self.selectedShippingOption = _shippingOptions[index];
+    _selectedItem = newlySelectedItem;
+  }
+  [_delegate shippingOptionSelectionViewController:self
+                            selectedShippingOption:self.selectedShippingOption];
+}
+
+#pragma mark MDCCollectionViewStylingDelegate
+
+- (CGFloat)collectionView:(UICollectionView*)collectionView
+    cellHeightAtIndexPath:(NSIndexPath*)indexPath {
+  return MDCCellDefaultTwoLineHeight;
+}
+
+@end