[iOS] Use new scroll delegate + Rename feed wrapper

Uses new feed initializer with custom scroll delegate. Reorders
component creation in NewTabPageCoordinator so that delegates can be
passed appropriately. Renamed DiscoverFeedViewController to
DiscoverFeedWrapperViewController for clarity on what it does.

Bug: 1114792
Change-Id: Iccdc7bf0efeda2252e0937d8665f1c33b09d9b87
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2593471
Commit-Queue: Adam Trudeau-Arcaro <adamta@google.com>
Reviewed-by: Sergio Collazos <sczs@chromium.org>
Cr-Commit-Position: refs/heads/master@{#837432}

ios/chrome/browser/ui/ntp/BUILD.gn

@@ -54,8 +54,8 @@ source_set("util") {
 source_set("ntp_internal") {
   configs += [ "//build/config/compiler:enable_arc" ]
   sources = [
-    "discover_feed_view_controller.h",
-    "discover_feed_view_controller.mm",
+    "discover_feed_wrapper_view_controller.h",
+    "discover_feed_wrapper_view_controller.mm",
     "incognito_view.h",
     "incognito_view.mm",
     "incognito_view_controller.h",

ios/chrome/browser/ui/ntp/discover_feed_view_controller.h → ios/chrome/browser/ui/ntp/discover_feed_wrapper_view_controller.h

@@ -2,14 +2,14 @@
 // 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_NTP_DISCOVER_FEED_VIEW_CONTROLLER_H_
-#define IOS_CHROME_BROWSER_UI_NTP_DISCOVER_FEED_VIEW_CONTROLLER_H_
+#ifndef IOS_CHROME_BROWSER_UI_NTP_DISCOVER_FEED_WRAPPER_VIEW_CONTROLLER_H_
+#define IOS_CHROME_BROWSER_UI_NTP_DISCOVER_FEED_WRAPPER_VIEW_CONTROLLER_H_
 
 #import <UIKit/UIKit.h>
 
 // View controller wrapping a Discover feed view controller
 // (|self.discoverFeed|) originating from the provider.
-@interface DiscoverFeedViewController : UIViewController
+@interface DiscoverFeedWrapperViewController : UIViewController
 
 // Feed view controller being contained by this view controller. This is the
 // view controller that is wrapped by this view controller.
@@ -30,4 +30,4 @@
 
 @end
 
-#endif  // IOS_CHROME_BROWSER_UI_NTP_DISCOVER_FEED_VIEW_CONTROLLER_H_
+#endif  // IOS_CHROME_BROWSER_UI_NTP_DISCOVER_FEED_WRAPPER_VIEW_CONTROLLER_H_

ios/chrome/browser/ui/ntp/discover_feed_view_controller.mm → ios/chrome/browser/ui/ntp/discover_feed_wrapper_view_controller.mm

@@ -4,14 +4,14 @@
 
 #import <UIKit/UIKit.h>
 
-#import "ios/chrome/browser/ui/ntp/discover_feed_view_controller.h"
+#import "ios/chrome/browser/ui/ntp/discover_feed_wrapper_view_controller.h"
 #import "ios/chrome/common/ui/util/constraints_ui_util.h"
 
 #if !defined(__has_feature) || !__has_feature(objc_arc)
 #error "This file requires ARC support."
 #endif
 
-@implementation DiscoverFeedViewController
+@implementation DiscoverFeedWrapperViewController
 
 - (instancetype)initWithDiscoverFeedViewController:
     (UIViewController*)discoverFeed {

ios/chrome/browser/ui/ntp/new_tab_page_coordinator.mm

@@ -14,7 +14,7 @@
 #import "ios/chrome/browser/ui/main/scene_state.h"
 #import "ios/chrome/browser/ui/main/scene_state_browser_agent.h"
 #import "ios/chrome/browser/ui/main/scene_state_observer.h"
-#import "ios/chrome/browser/ui/ntp/discover_feed_view_controller.h"
+#import "ios/chrome/browser/ui/ntp/discover_feed_wrapper_view_controller.h"
 #import "ios/chrome/browser/ui/ntp/incognito_view_controller.h"
 #import "ios/chrome/browser/ui/ntp/new_tab_page_feature.h"
 #import "ios/chrome/browser/ui/ntp/new_tab_page_view_controller.h"
@@ -41,7 +41,7 @@
 
 // View controller wrapping the Discover feed.
 @property(nonatomic, strong)
-    DiscoverFeedViewController* discoverFeedViewController;
+    DiscoverFeedWrapperViewController* discoverFeedWrapperViewController;
 
 // View controller for the incognito NTP.
 @property(nonatomic, strong) IncognitoViewController* incognitoViewController;
@@ -97,19 +97,22 @@
     [self.contentSuggestionsCoordinator start];
 
     if (IsRefactoredNTP()) {
-      // TODO(crbug.com/1114792): Use function with scroll delegate.
-      UIViewController* discoverFeed =
+      self.ntpViewController = [[NewTabPageViewController alloc]
+          initWithContentSuggestionsViewController:
+              self.contentSuggestionsCoordinator.viewController];
+
+      UIViewController* discoverFeedViewController =
           ios::GetChromeBrowserProvider()
               ->GetDiscoverFeedProvider()
-              ->NewFeedViewController(self.browser);
+              ->NewFeedViewControllerWithScrollDelegate(self.browser,
+                                                        self.ntpViewController);
 
-      self.discoverFeedViewController = [[DiscoverFeedViewController alloc]
-          initWithDiscoverFeedViewController:discoverFeed];
+      self.discoverFeedWrapperViewController =
+          [[DiscoverFeedWrapperViewController alloc]
+              initWithDiscoverFeedViewController:discoverFeedViewController];
 
-      self.ntpViewController = [[NewTabPageViewController alloc]
-          initWithDiscoverFeedViewController:self.discoverFeedViewController
-            contentSuggestionsViewController:self.contentSuggestionsCoordinator
-                                                 .viewController];
+      self.ntpViewController.discoverFeedWrapperViewController =
+          self.discoverFeedWrapperViewController;
     }
 
     base::RecordAction(base::UserMetricsAction("MobileNTPShowMostVisited"));
@@ -134,6 +137,8 @@
   [sceneState removeObserver:self];
   self.contentSuggestionsCoordinator = nil;
   self.incognitoViewController = nil;
+  self.ntpViewController = nil;
+  self.discoverFeedWrapperViewController = nil;
   self.started = NO;
 }
 

ios/chrome/browser/ui/ntp/new_tab_page_view_controller.h

@@ -8,21 +8,22 @@
 #import <UIKit/UIKit.h>
 
 @class ContentSuggestionsViewController;
-@class DiscoverFeedViewController;
+@class DiscoverFeedWrapperViewController;
 
 // View controller containing all the content presented on a standard,
 // non-incognito new tab page.
 @interface NewTabPageViewController : UIViewController <UIScrollViewDelegate>
 
+// View controller wrapping the Discover feed.
+@property(nonatomic, strong)
+    DiscoverFeedWrapperViewController* discoverFeedWrapperViewController;
+
 // Initializes view controller with NTP content view controllers.
 // |discoverFeedViewController| represents the Discover feed for suggesting
 // articles. |contentSuggestionsViewController| represents other content
 // suggestions, such as the most visited site tiles.
-- (instancetype)initWithDiscoverFeedViewController:
-                    (DiscoverFeedViewController*)discoverFeedViewController
-                  contentSuggestionsViewController:
-                      (UICollectionViewController*)
-                          contentSuggestionsViewController
+- (instancetype)initWithContentSuggestionsViewController:
+    (UICollectionViewController*)contentSuggestionsViewController
     NS_DESIGNATED_INITIALIZER;
 
 - (instancetype)initWithNibName:(NSString*)name

ios/chrome/browser/ui/ntp/new_tab_page_view_controller.mm

@@ -6,7 +6,8 @@
 
 #import "ios/chrome/browser/ui/ntp/new_tab_page_view_controller.h"
 
-#import "ios/chrome/browser/ui/ntp/discover_feed_view_controller.h"
+#import "base/check.h"
+#import "ios/chrome/browser/ui/ntp/discover_feed_wrapper_view_controller.h"
 #import "ios/chrome/common/ui/util/constraints_ui_util.h"
 
 #if !defined(__has_feature) || !__has_feature(objc_arc)
@@ -15,10 +16,6 @@
 
 @interface NewTabPageViewController ()
 
-// View controller representing the Discover feed.
-@property(nonatomic, strong)
-    DiscoverFeedViewController* discoverFeedViewController;
-
 // View controller representing the NTP content suggestions. These suggestions
 // include the most visited site tiles, the shortcut tiles, the fake omnibox and
 // the Google doodle.
@@ -29,14 +26,10 @@
 
 @implementation NewTabPageViewController
 
-- (instancetype)initWithDiscoverFeedViewController:
-                    (DiscoverFeedViewController*)discoverFeedViewController
-                  contentSuggestionsViewController:
-                      (UICollectionViewController*)
-                          contentSuggestionsViewController {
+- (instancetype)initWithContentSuggestionsViewController:
+    (UICollectionViewController*)contentSuggestionsViewController {
   self = [super initWithNibName:nil bundle:nil];
   if (self) {
-    _discoverFeedViewController = discoverFeedViewController;
     _contentSuggestionsViewController = contentSuggestionsViewController;
   }
 
@@ -46,25 +39,27 @@
 - (void)viewDidLoad {
   [super viewDidLoad];
 
-  UIView* discoverFeedView = self.discoverFeedViewController.view;
+  DCHECK(self.discoverFeedWrapperViewController);
+
+  UIView* discoverFeedView = self.discoverFeedWrapperViewController.view;
 
-  [self.discoverFeedViewController willMoveToParentViewController:self];
-  [self addChildViewController:self.discoverFeedViewController];
+  [self.discoverFeedWrapperViewController willMoveToParentViewController:self];
+  [self addChildViewController:self.discoverFeedWrapperViewController];
   [self.view addSubview:discoverFeedView];
-  [self.discoverFeedViewController didMoveToParentViewController:self];
+  [self.discoverFeedWrapperViewController didMoveToParentViewController:self];
 
   discoverFeedView.translatesAutoresizingMaskIntoConstraints = NO;
   AddSameConstraints(discoverFeedView, self.view);
 
   [self.contentSuggestionsViewController
-      willMoveToParentViewController:self.discoverFeedViewController
+      willMoveToParentViewController:self.discoverFeedWrapperViewController
                                          .discoverFeed];
-  [self.discoverFeedViewController.discoverFeed
+  [self.discoverFeedWrapperViewController.discoverFeed
       addChildViewController:self.contentSuggestionsViewController];
-  [self.discoverFeedViewController.feedCollectionView
+  [self.discoverFeedWrapperViewController.feedCollectionView
       addSubview:self.contentSuggestionsViewController.view];
   [self.contentSuggestionsViewController
-      didMoveToParentViewController:self.discoverFeedViewController
+      didMoveToParentViewController:self.discoverFeedWrapperViewController
                                         .discoverFeed];
 }
 
@@ -78,7 +73,7 @@
   self.contentSuggestionsViewController.view.frame =
       CGRectMake(0, -collectionView.contentSize.height,
                  self.view.frame.size.width, collectionView.contentSize.height);
-  self.discoverFeedViewController.feedCollectionView.contentInset =
+  self.discoverFeedWrapperViewController.feedCollectionView.contentInset =
       UIEdgeInsetsMake(collectionView.contentSize.height, 0, 0, 0);
 }