Upstream ios/showcase source code.

ios/showcase/core/showcase_view_controller.mm

+// Copyright 2016 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/showcase/core/showcase_view_controller.h"
+
+#import "base/logging.h"
+#import "ios/showcase/common/coordinator.h"
+
+#if !defined(__has_feature) || !__has_feature(objc_arc)
+#error "This file requires ARC support."
+#endif
+
+namespace showcase {
+
+NSString* const kClassForDisplayKey = @"classForDisplay";
+NSString* const kClassForInstantiationKey = @"classForInstantiation";
+NSString* const kUseCaseKey = @"useCase";
+
+}  // namespace showcase
+
+@interface ShowcaseViewController ()<UITableViewDataSource,
+                                     UITableViewDelegate,
+                                     UISearchResultsUpdating>
+
+// Search controller that contains search bar.
+@property(nonatomic, strong) UISearchController* searchController;
+
+// Full data set displayed when tableView is not filtered.
+@property(nonatomic, strong) NSArray<showcase::ModelRow*>* allRows;
+
+// Displayed rows in tableView.
+@property(nonatomic, strong) NSArray<showcase::ModelRow*>* displayedRows;
+
+// Selected coordinator.
+@property(nonatomic, strong) id<Coordinator> activeCoordinator;
+
+@end
+
+@implementation ShowcaseViewController
+@synthesize searchController = _searchController;
+@synthesize allRows = _allRows;
+@synthesize displayedRows = _displayedRows;
+@synthesize activeCoordinator = _activeCoordinator;
+
+- (instancetype)initWithRows:(NSArray<showcase::ModelRow*>*)rows {
+  self = [super initWithStyle:UITableViewStylePlain];
+  if (self) {
+    self.allRows = [rows copy];
+    // Default to displaying all rows.
+    self.displayedRows = self.allRows;
+  }
+  return self;
+}
+
+#pragma mark - UIViewController
+
+- (void)viewDidLoad {
+  [super viewDidLoad];
+
+  self.title = @"Showcase";
+  self.tableView.tableFooterView = [[UIView alloc] init];
+  self.tableView.rowHeight = 70.0;
+
+  self.searchController =
+      [[UISearchController alloc] initWithSearchResultsController:nil];
+  self.searchController.searchResultsUpdater = self;
+  self.searchController.dimsBackgroundDuringPresentation = NO;
+  self.tableView.tableHeaderView = self.searchController.searchBar;
+
+  // Presentation of searchController will walk up the view controller hierarchy
+  // until it finds the root view controller or one that defines a presentation
+  // context. Make this class the presentation context so that the search
+  // controller does not present on top of the navigation controller.
+  self.definesPresentationContext = YES;
+}
+
+- (void)viewDidAppear:(BOOL)animated {
+  [super viewDidAppear:animated];
+  // Resets the current coordinator whenever the navigation controller pops
+  // back to this view controller.
+  self.activeCoordinator = nil;
+}
+
+#pragma mark - Table view data source
+
+- (NSInteger)tableView:(UITableView*)tableView
+    numberOfRowsInSection:(NSInteger)section {
+  return self.displayedRows.count;
+}
+
+- (UITableViewCell*)tableView:(UITableView*)tableView
+        cellForRowAtIndexPath:(NSIndexPath*)indexPath {
+  UITableViewCell* cell = [tableView dequeueReusableCellWithIdentifier:@"cell"];
+  if (!cell) {
+    cell = [[UITableViewCell alloc] initWithStyle:UITableViewCellStyleSubtitle
+                                  reuseIdentifier:@"cell"];
+    cell.accessoryType = UITableViewCellAccessoryDisclosureIndicator;
+  }
+  showcase::ModelRow* row = self.displayedRows[indexPath.row];
+  cell.textLabel.text = row[showcase::kClassForDisplayKey];
+  cell.detailTextLabel.text = row[showcase::kUseCaseKey];
+  return cell;
+}
+
+#pragma mark - Table view delegate
+
+- (void)tableView:(UITableView*)tableView
+    didSelectRowAtIndexPath:(NSIndexPath*)indexPath {
+  showcase::ModelRow* row = self.displayedRows[indexPath.row];
+  Class classForInstantiation =
+      NSClassFromString(row[showcase::kClassForInstantiationKey]);
+  if ([classForInstantiation isSubclassOfClass:[UIViewController class]]) {
+    UIViewController* viewController = [[classForInstantiation alloc] init];
+    viewController.title = row[showcase::kUseCaseKey];
+    [self.navigationController pushViewController:viewController animated:YES];
+  } else if ([classForInstantiation
+                 conformsToProtocol:@protocol(Coordinator)]) {
+    self.activeCoordinator = [[classForInstantiation alloc] init];
+    self.activeCoordinator.baseViewController = self.navigationController;
+    [self.activeCoordinator start];
+  } else {
+    NOTREACHED();
+  }
+}
+
+#pragma mark - UISearchResultsUpdating
+
+- (void)updateSearchResultsForSearchController:
+    (UISearchController*)searchController {
+  [self filterContentForSearchText:searchController.searchBar.text];
+}
+
+#pragma mark - Private
+
+// Filters |allRows| for |searchText| and reloads the tableView with
+// animation. If |searchText| is empty, tableView will be loaded with |allRows|.
+- (void)filterContentForSearchText:(NSString*)searchText {
+  NSArray<showcase::ModelRow*>* newFilteredRows = self.allRows;
+
+  if (![self.searchController.searchBar.text isEqualToString:@""]) {
+    // The search is case-insensitive and searches both displayed texts.
+    NSIndexSet* matchingRows =
+        [self.allRows indexesOfObjectsPassingTest:^BOOL(
+                          showcase::ModelRow* row, NSUInteger idx, BOOL* stop) {
+          return [row[showcase::kClassForDisplayKey]
+                     localizedCaseInsensitiveContainsString:searchText] ||
+                 [row[showcase::kUseCaseKey]
+                     localizedCaseInsensitiveContainsString:searchText];
+        }];
+    newFilteredRows = [self.allRows objectsAtIndexes:matchingRows];
+  }
+
+  NSArray<NSIndexPath*>* indexPathsToInsert =
+      [self indexPathsToInsertFromArray:self.displayedRows
+                                toArray:newFilteredRows
+                       indexPathSection:0];
+  NSArray<NSIndexPath*>* indexPathsToDelete =
+      [self indexPathsToDeleteFromArray:self.displayedRows
+                                toArray:newFilteredRows
+                       indexPathSection:0];
+
+  [self.tableView beginUpdates];
+  [self.tableView insertRowsAtIndexPaths:indexPathsToInsert
+                        withRowAnimation:UITableViewRowAnimationFade];
+  [self.tableView deleteRowsAtIndexPaths:indexPathsToDelete
+                        withRowAnimation:UITableViewRowAnimationFade];
+  self.displayedRows = newFilteredRows;
+  [self.tableView endUpdates];
+}
+
+// Returns indexPaths that need to be inserted into the tableView.
+- (NSArray<NSIndexPath*>*)indexPathsToInsertFromArray:(NSArray*)fromArray
+                                              toArray:(NSArray*)toArray
+                                     indexPathSection:(NSUInteger)section {
+  NSMutableArray<NSIndexPath*>* indexPathsToInsert =
+      [[NSMutableArray alloc] init];
+  for (NSUInteger row = 0; row < toArray.count; row++) {
+    if (![fromArray containsObject:toArray[row]]) {
+      [indexPathsToInsert
+          addObject:[NSIndexPath indexPathForRow:row inSection:section]];
+    }
+  }
+  return indexPathsToInsert;
+}
+
+// Returns indexPaths that need to be deleted from the tableView.
+- (NSArray<NSIndexPath*>*)indexPathsToDeleteFromArray:(NSArray*)fromArray
+                                              toArray:(NSArray*)toArray
+                                     indexPathSection:(NSUInteger)section {
+  NSMutableArray<NSIndexPath*>* indexPathsToDelete =
+      [[NSMutableArray alloc] init];
+  for (NSUInteger row = 0; row < fromArray.count; row++) {
+    if (![toArray containsObject:fromArray[row]]) {
+      [indexPathsToDelete
+          addObject:[NSIndexPath indexPathForRow:row inSection:section]];
+    }
+  }
+  return indexPathsToDelete;
+}
+
+@end