Convert main NTP panel to UIViewController.

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

 // Copyright 2013 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/ntp/google_landing_controller.h"
 
 #include <algorithm>
 
 #include "base/i18n/case_conversion.h"
 #import "base/ios/weak_nsobject.h"
@@ skipping 173 matching lines @@
 
 @end
 
 @interface GoogleLandingController ()<MostVisitedSitesObserving,
                                       OverscrollActionsControllerDelegate,
                                       UICollectionViewDataSource,
                                       UICollectionViewDelegate,
                                       UICollectionViewDelegateFlowLayout,
                                       UIGestureRecognizerDelegate,
                                       WhatsNewHeaderViewDelegate> {
-  // The main view.
-  base::scoped_nsobject<GoogleLandingView> _view;
-
   // Fake omnibox.
   base::scoped_nsobject<UIButton> _searchTapTarget;
 
   // Controller to fetch and show doodles or a default Google logo.
   base::scoped_nsprotocol<id<LogoVendor>> _doodleController;
 
   // Most visited data from the MostVisitedSites service (copied upon receiving
   // the callback).
   ntp_tiles::NTPTilesVector _mostVisitedData;
 
@@ skipping 179 matching lines @@
     _tapGestureRecognizer.reset([[UITapGestureRecognizer alloc]
         initWithTarget:self
                 action:@selector(blurOmnibox)]);
     [_tapGestureRecognizer setDelegate:self];
     _swipeGestureRecognizer.reset([[UISwipeGestureRecognizer alloc]
         initWithTarget:self
                 action:@selector(blurOmnibox)]);
     [_swipeGestureRecognizer
         setDirection:UISwipeGestureRecognizerDirectionDown];
 
-    _view.reset(
-        [[GoogleLandingView alloc] initWithFrame:[UIScreen mainScreen].bounds]);
-    [_view setAutoresizingMask:UIViewAutoresizingFlexibleHeight |
-                               UIViewAutoresizingFlexibleWidth];
-    [_view setFrameDelegate:self];
-
     _focuser.reset(focuser);
     _webToolbarDelegate.reset(webToolbarDelegate);
     _tabModel.reset([tabModel retain]);
 
     _scrolledToTop = NO;
     _animateHeader = YES;
-    // Initialise |shiftTilesDownStartTime| to a sentinel value to indicate that
-    // the animation has not yet started.
-    _shiftTilesDownStartTime = -1;
-    _mostVisitedCellSize =
-        [GoogleLandingController mostVisitedCellSizeForView:_view];
-    [self addDoodle];
-    [self addSearchField];
-    [self addMostVisited];
-    [self addOverscrollActions];
-    [self reload];
   }
   return self;
 }
 
+- (void)loadView {
+  self.view =
+      [[GoogleLandingView alloc] initWithFrame:[UIScreen mainScreen].bounds];
+  [self.view setAutoresizingMask:UIViewAutoresizingFlexibleHeight |
+                                 UIViewAutoresizingFlexibleWidth];
+  [(GoogleLandingView*)self.view setFrameDelegate:self];

[rohitrao (ping after 24h), 2017/04/12 12:45:09]

You can redeclare the |view| property to be a GoogleLandingView*, to avoid
casting everywhere.

[justincohen, 2017/04/12 14:23:12]

Done.

+  // Initialise |shiftTilesDownStartTime| to a sentinel value to indicate that
+  // the animation has not yet started.
+  _shiftTilesDownStartTime = -1;
+  _mostVisitedCellSize =
+      [GoogleLandingController mostVisitedCellSizeForView:self.view];
+  [self addDoodle];
+  [self addSearchField];
+  [self addMostVisited];
+  [self addOverscrollActions];
+  [self reload];
+}
+
 + (CGSize)mostVisitedCellSizeForView:(UIView*)view {
   if (IsIPadIdiom()) {
     // On iPads, split-screen and slide-over may require showing smaller cells.
     CGSize maximumCellSize = [MostVisitedCell maximumSize];
     CGSize viewSize = view.bounds.size;
     CGFloat smallestDimension =
         viewSize.height > viewSize.width ? viewSize.width : viewSize.height;
     CGFloat cellWidth = AlignValueToPixel(
         (smallestDimension - 3 * [self.class mostVisitedCellPadding]) / 2);
     if (cellWidth < maximumCellSize.width) {
@@ skipping 45 matching lines @@
     // Call -scrollViewDidScroll: so that the omnibox's frame is adjusted for
     // the scroll view's offset.
     [self scrollViewDidScroll:_mostVisitedView];
   };
 
   dispatch_after(dispatch_time(DISPATCH_TIME_NOW, 0), dispatch_get_main_queue(),
                  layoutBlock);
 }
 
 - (CGFloat)viewWidth {
-  return [_view frame].size.width;
+  return [self.view frame].size.width;
 }
 
 - (int)numberOfColumns {
   CGFloat width = [self viewWidth];
   CGFloat padding = [self.class mostVisitedCellPadding];
   // Try to fit 4 columns.
   if (width >= 5 * padding + _mostVisitedCellSize.width * 4)
     return 4;
   // Try to fit 3 columns.
   if (width >= 4 * padding + _mostVisitedCellSize.width * 3)
@@ skipping 305 matching lines @@
 }
 
 - (void)resetSectionInset {
   UICollectionViewFlowLayout* flowLayout =
       (UICollectionViewFlowLayout*)[_mostVisitedView collectionViewLayout];
   [flowLayout setSectionInset:UIEdgeInsetsZero];
 }
 
 - (void)updateSubviewFrames {
   _mostVisitedCellSize =
-      [GoogleLandingController mostVisitedCellSizeForView:_view];
+      [GoogleLandingController mostVisitedCellSizeForView:self.view];
   UICollectionViewFlowLayout* flowLayout =
       base::mac::ObjCCastStrict<UICollectionViewFlowLayout>(
           [_mostVisitedView collectionViewLayout]);
   [flowLayout setItemSize:_mostVisitedCellSize];
   [[_doodleController view] setFrame:[self doodleFrame]];
 
   [self setFlowLayoutInset:flowLayout];
   [flowLayout invalidateLayout];
   [_promoHeaderView setSideMargin:[self leftMargin]];
 
@@ skipping 27 matching lines @@
 
   if (!_viewLoaded) {
     _viewLoaded = YES;
     [_doodleController fetchDoodle];
   }
   [self.delegate updateNtpBarShadowForPanelController:self];
 }
 
 // Initialize and add a panel with most visited sites.
 - (void)addMostVisited {
-  CGRect mostVisitedFrame = [_view bounds];
+  CGRect mostVisitedFrame = [self.view bounds];
   base::scoped_nsobject<UICollectionViewFlowLayout> flowLayout;
   if (IsIPadIdiom())
     flowLayout.reset([[UICollectionViewFlowLayout alloc] init]);
   else
     flowLayout.reset([[MostVisitedLayout alloc] init]);
 
   [flowLayout setScrollDirection:UICollectionViewScrollDirectionVertical];
   [flowLayout setItemSize:_mostVisitedCellSize];
   [flowLayout setMinimumInteritemSpacing:8];
   [flowLayout setMinimumLineSpacing:[self.class mostVisitedCellPadding]];
@@ skipping 12 matching lines @@
   [_mostVisitedView setShowsHorizontalScrollIndicator:NO];
   [_mostVisitedView setShowsVerticalScrollIndicator:NO];
   [_mostVisitedView registerClass:[WhatsNewHeaderView class]
        forSupplementaryViewOfKind:UICollectionElementKindSectionHeader
               withReuseIdentifier:@"whatsNew"];
   [_mostVisitedView registerClass:[NewTabPageHeaderView class]
        forSupplementaryViewOfKind:UICollectionElementKindSectionHeader
               withReuseIdentifier:@"header"];
   [_mostVisitedView setAccessibilityIdentifier:@"Google Landing"];
 
-  [_view addSubview:_mostVisitedView];
+  [self.view addSubview:_mostVisitedView];
   _most_visited_sites =
       IOSMostVisitedSitesFactory::NewForBrowserState(_browserState);
   _most_visited_observer_bridge.reset(
       new ntp_tiles::MostVisitedSitesObserverBridge(self));
   _most_visited_sites->SetMostVisitedURLsObserver(
       _most_visited_observer_bridge.get(), kMaxNumMostVisitedFavicons);
 }
 
 - (void)updateSearchField {
   NSArray* constraints =
@@ skipping 26 matching lines @@
 - (void)locationBarBecomesFirstResponder {
   if (!_isShowing)
     return;
 
   _omniboxFocused = YES;
   [self shiftTilesUp];
 }
 
 - (void)shiftTilesUp {
   _scrolledToTop = YES;
-  // Add gesture recognizer to background |_view| when omnibox is focused.
-  [_view addGestureRecognizer:_tapGestureRecognizer];
-  [_view addGestureRecognizer:_swipeGestureRecognizer];
+  // Add gesture recognizer to background |self.view| when omnibox is focused.
+  [self.view addGestureRecognizer:_tapGestureRecognizer];
+  [self.view addGestureRecognizer:_swipeGestureRecognizer];
 
   CGFloat pinnedOffsetY = [self pinnedOffsetY];
   _animateHeader = !IsIPadIdiom();
 
   [UIView animateWithDuration:0.25
       animations:^{
         if ([_mostVisitedView contentOffset].y < pinnedOffsetY) {
           [_mostVisitedView setContentOffset:CGPointMake(0, pinnedOffsetY)];
           [[_mostVisitedView collectionViewLayout] invalidateLayout];
         }
@@ skipping 44 matching lines @@
     [_searchTapTarget setHidden:NO];
     [_focuser onFakeboxBlur];
   }
 
   // Reload most visited sites in case the number of placeholder cells needs to
   // be updated after an orientation change.
   [_mostVisitedView reloadData];
 
   // Reshow views that are within range of the most visited collection view
   // (if necessary).
-  [_view removeGestureRecognizer:_tapGestureRecognizer];
-  [_view removeGestureRecognizer:_swipeGestureRecognizer];
+  [self.view removeGestureRecognizer:_tapGestureRecognizer];
+  [self.view removeGestureRecognizer:_swipeGestureRecognizer];
 
   // CADisplayLink is used for this animation instead of the standard UIView
   // animation because the standard animation did not properly convert the
   // fakebox from its scrolled up mode to its scrolled down mode. Specifically,
   // calling |UICollectionView reloadData| adjacent to the standard animation
   // caused the fakebox's views to jump incorrectly. CADisplayLink avoids this
   // problem because it allows |shiftTilesDownAnimationDidFire| to directly
   // control each frame.
   CADisplayLink* link = [CADisplayLink
       displayLinkWithTarget:self
@@ skipping 463 matching lines @@
   [_contextMenuCoordinator stop];
 }
 
 - (void)dismissKeyboard {
 }
 
 - (void)setScrollsToTop:(BOOL)enable {
 }
 
 - (CGFloat)alphaForBottomShadow {
-  // Get the frame of the bottommost cell in |_view|'s coordinate system.
+  // Get the frame of the bottommost cell in |self.view|'s coordinate system.
   NSInteger section = SectionWithMostVisited;
   // Account for the fact that the tableview may not yet contain
   // |numberOfNonEmptyTilesShown| tiles because it hasn't been updated yet.
   NSUInteger lastItemIndex =
       std::min([_mostVisitedView numberOfItemsInSection:SectionWithMostVisited],
                [self numberOfNonEmptyTilesShown]) -
       1;
   DCHECK(lastItemIndex >= 0);
   NSIndexPath* lastCellIndexPath =
       [NSIndexPath indexPathForItem:lastItemIndex inSection:section];
   UICollectionViewLayoutAttributes* attributes =
       [_mostVisitedView layoutAttributesForItemAtIndexPath:lastCellIndexPath];
   CGRect lastCellFrame = attributes.frame;
   CGRect cellFrameInSuperview =
       [_mostVisitedView convertRect:lastCellFrame toView:self.view];
 
-  // Calculate when the bottom of the cell passes through the bottom of |_view|.
+  // Calculate when the bottom of the cell passes through the bottom of
+  // |self.view|.
   CGFloat maxY = CGRectGetMaxY(cellFrameInSuperview);
   CGFloat viewHeight = CGRectGetHeight(self.view.frame);
 
   CGFloat pixelsBelowFrame = maxY - viewHeight;
   CGFloat alpha = pixelsBelowFrame / kNewTabPageDistanceToFadeShadow;
   alpha = MIN(MAX(alpha, 0), 1);
   return alpha;
 }
 
-- (UIView*)view {
-  return _view;
-}
-
 #pragma mark - LogoAnimationControllerOwnerOwner
 
 - (id<LogoAnimationControllerOwner>)logoAnimationControllerOwner {
   return [_doodleController logoAnimationControllerOwner];
 }
 
 #pragma mark - UIScrollViewDelegate Methods.
 
 - (void)scrollViewDidScroll:(UIScrollView*)scrollView {
   [self.delegate updateNtpBarShadowForPanelController:self];
@@ skipping 171 matching lines @@
   if (!view) {
     return nil;
   }
   if ([view isKindOfClass:aClass]) {
     return view;
   }
   return [self nearestAncestorOfView:[view superview] withClass:aClass];
 }
 
 @end