Implement the view revealing animatee protocol in the toolbar.

- Implement the view revealing animatee methods: when revealing the
thumb strip view, the toolbar's top right and top left corners will
become rounded.
- Add a pan gesture recognizer to reveal/hide the thumb strip by
dragging down/up the toolbar.

Bug: 1094335
Change-Id: Ib024cc033e2bf4f270c006330a3f972624b495eb
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2315346
Commit-Queue: Roberto Moura <mouraroberto@google.com>
Reviewed-by: Mark Cogan <marq@chromium.org>
Reviewed-by: edchin <edchin@chromium.org>
Cr-Commit-Position: refs/heads/master@{#800059}

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

@@ -45,6 +45,7 @@ source_set("toolbar") {
     "//ios/chrome/browser/ui/coordinators:chrome_coordinators",
     "//ios/chrome/browser/ui/fullscreen",
     "//ios/chrome/browser/ui/fullscreen:feature_flags",
+    "//ios/chrome/browser/ui/gestures",
     "//ios/chrome/browser/ui/location_bar",
     "//ios/chrome/browser/ui/ntp",
     "//ios/chrome/browser/ui/ntp:util",
@@ -94,6 +95,7 @@ source_set("toolbar_ui") {
     "//ios/chrome/browser/ui/activity_services/requirements",
     "//ios/chrome/browser/ui/commands",
     "//ios/chrome/browser/ui/fullscreen:ui",
+    "//ios/chrome/browser/ui/gestures",
     "//ios/chrome/browser/ui/ntp:ntp",
     "//ios/chrome/browser/ui/orchestrator",
     "//ios/chrome/browser/ui/popup_menu/public",

ios/chrome/browser/ui/toolbar/primary_toolbar_coordinator.h

@@ -11,6 +11,8 @@
 @protocol ActivityServicePositioner;
 @protocol OmniboxPopupPresenterDelegate;
 @protocol ToolbarCoordinatorDelegate;
+@class ViewRevealingVerticalPanHandler;
+@protocol ViewRevealingAnimatee;
 
 // Coordinator for the primary part, the one containing the omnibox, of the
 // adaptive toolbar.
@@ -25,6 +27,10 @@
 @property(nonatomic, weak) id<OmniboxPopupPresenterDelegate>
     popupPresenterDelegate;
 
+// A reference to the view controller that implements the view revealing
+// vertical pan handler delegate methods.
+@property(nonatomic, weak, readonly) id<ViewRevealingAnimatee> animatee;
+
 // Positioner for activity services attached to the toolbar
 - (id<ActivityServicePositioner>)activityServicePositioner;
 
@@ -39,6 +45,10 @@
 // transition to the expanded location bar state of the view controller.
 - (void)transitionToLocationBarFocusedState:(BOOL)focused;
 
+// Sets the pan gesture handler for the toolbar controller.
+- (void)setPanGestureHandler:
+    (ViewRevealingVerticalPanHandler*)panGestureHandler;
+
 @end
 
 #endif  // IOS_CHROME_BROWSER_UI_TOOLBAR_PRIMARY_TOOLBAR_COORDINATOR_H_

ios/chrome/browser/ui/toolbar/primary_toolbar_coordinator.mm

@@ -148,6 +148,15 @@
                              animated:self.enableAnimationsForOmniboxFocus];
 }
 
+- (id<ViewRevealingAnimatee>)animatee {
+  return self.viewController;
+}
+
+- (void)setPanGestureHandler:
+    (ViewRevealingVerticalPanHandler*)panGestureHandler {
+  self.viewController.panGestureHandler = panGestureHandler;
+}
+
 #pragma mark - PrimaryToolbarViewControllerDelegate
 
 - (void)viewControllerTraitCollectionDidChange:

ios/chrome/browser/ui/toolbar/primary_toolbar_view.h

@@ -67,6 +67,10 @@
 @property(nonatomic, strong, readwrite)
     NSLayoutConstraint* locationBarBottomConstraint;
 
+// Whether the top-left and top-right corners of the toolbar are rounded or
+// square.
+@property(nonatomic, assign) BOOL topCornersRounded;
+
 // Sets all the subviews and constraints of the view. The |topSafeAnchor| needs
 // to be set before calling this.
 - (void)setUp;

ios/chrome/browser/ui/toolbar/primary_toolbar_view.mm

@@ -169,6 +169,11 @@
   self.fakeOmniboxTarget = nil;
 }
 
+- (void)setTopCornersRounded:(BOOL)rounded {
+  _topCornersRounded = rounded;
+  self.layer.cornerRadius = rounded ? kTopCornerRadius : 0;
+}
+
 #pragma mark - UIView
 
 - (CGSize)intrinsicContentSize {
@@ -195,6 +200,9 @@
 - (void)setUpToolbarBackground {
   self.backgroundColor =
       self.buttonFactory.toolbarConfiguration.backgroundColor;
+  if (base::FeatureList::IsEnabled(kExpandedTabStrip)) {
+    self.layer.maskedCorners = kCALayerMinXMinYCorner | kCALayerMaxXMinYCorner;
+  }
 
   self.contentView = self;
 }

ios/chrome/browser/ui/toolbar/primary_toolbar_view_controller.h

@@ -7,23 +7,29 @@
 
 #import "ios/chrome/browser/ui/activity_services/requirements/activity_service_positioner.h"
 #import "ios/chrome/browser/ui/fullscreen/fullscreen_ui_element.h"
+#import "ios/chrome/browser/ui/gestures/view_revealing_animatee.h"
 #import "ios/chrome/browser/ui/orchestrator/toolbar_animatee.h"
 #import "ios/chrome/browser/ui/toolbar/adaptive_toolbar_view_controller.h"
 
 @protocol PrimaryToolbarViewControllerDelegate;
+@class ViewRevealingVerticalPanHandler;
 
 // ViewController for the primary toobar part of the adaptive toolbar. It is the
 // part always displayed and containing the location bar.
 @interface PrimaryToolbarViewController
-    : AdaptiveToolbarViewController<ActivityServicePositioner,
-                                    FullscreenUIElement,
-                                    ToolbarAnimatee>
+    : AdaptiveToolbarViewController <ActivityServicePositioner,
+                                     FullscreenUIElement,
+                                     ToolbarAnimatee,
+                                     ViewRevealingAnimatee>
 
 @property(nonatomic, weak) id<PrimaryToolbarViewControllerDelegate> delegate;
 
 // Whether the omnibox should be hidden on NTP.
 @property(nonatomic, assign) BOOL shouldHideOmniboxOnNTP;
 
+// Pan gesture handler for the toolbar.
+@property(nonatomic, weak) ViewRevealingVerticalPanHandler* panGestureHandler;
+
 // Sets the location bar view controller, containing the omnibox.
 - (void)setLocationBarViewController:(UIViewController*)locationBarView;
 

ios/chrome/browser/ui/toolbar/primary_toolbar_view_controller.mm

@@ -10,6 +10,7 @@
 #import "ios/chrome/browser/ui/commands/browser_commands.h"
 #import "ios/chrome/browser/ui/commands/omnibox_commands.h"
 #import "ios/chrome/browser/ui/fullscreen/fullscreen_animator.h"
+#import "ios/chrome/browser/ui/gestures/view_revealing_vertical_pan_handler.h"
 #import "ios/chrome/browser/ui/toolbar/adaptive_toolbar_view_controller+subclassing.h"
 #import "ios/chrome/browser/ui/toolbar/buttons/toolbar_button.h"
 #import "ios/chrome/browser/ui/toolbar/buttons/toolbar_button_factory.h"
@@ -34,6 +35,8 @@
 @property(nonatomic, assign) BOOL isNTP;
 // The last fullscreen progress registered.
 @property(nonatomic, assign) CGFloat previousFullscreenProgress;
+// Pan Gesture Recognizer for the view revealing pan gesture handler.
+@property(nonatomic, weak) UIPanGestureRecognizer* panGestureRecognizer;
 @end
 
 @implementation PrimaryToolbarViewController
@@ -55,6 +58,26 @@
                         }];
 }
 
+- (void)setPanGestureHandler:
+    (ViewRevealingVerticalPanHandler*)panGestureHandler {
+  _panGestureHandler = panGestureHandler;
+  [self.view removeGestureRecognizer:self.panGestureRecognizer];
+
+  UIPanGestureRecognizer* panGestureRecognizer = [[UIPanGestureRecognizer alloc]
+      initWithTarget:panGestureHandler
+              action:@selector(handlePanGesture:)];
+  panGestureRecognizer.maximumNumberOfTouches = 1;
+  [self.view addGestureRecognizer:panGestureRecognizer];
+
+  self.panGestureRecognizer = panGestureRecognizer;
+}
+
+#pragma mark - viewRevealingAnimatee
+
+- (void)animateViewReveal:(BOOL)viewRevealed {
+  self.view.topCornersRounded = !viewRevealed;
+}
+
 #pragma mark - AdaptiveToolbarViewController
 
 - (void)updateForSideSwipeSnapshotOnNTP:(BOOL)onNTP {

ios/chrome/browser/ui/toolbar/public/toolbar_constants.h

@@ -98,6 +98,10 @@ extern NSString* const kToolbarNewTabButtonIdentifier;
 // Accessibility identifier of the cancel omnibox edit button.
 extern NSString* const kToolbarCancelOmniboxEditButtonIdentifier;
 
+// Round corner radius for top-left and top-right corners when thumb strip is
+// visible.
+extern const CGFloat kTopCornerRadius;
+
 // Font size for the TabGrid button containing the tab count.
 extern const NSInteger kTabGridButtonFontSize;
 

ios/chrome/browser/ui/toolbar/public/toolbar_constants.mm

@@ -58,6 +58,8 @@ const CGFloat kNonDynamicToolbarHeight = 14;
 const CGFloat kToolbarHeightFullscreen = 20;
 const CGFloat kNonDynamicToolbarHeightFullscreen = 3;
 
+const CGFloat kTopCornerRadius = 10;
+
 NSString* const kToolbarToolsMenuButtonIdentifier =
     @"kToolbarToolsMenuButtonIdentifier";
 NSString* const kToolbarStackButtonIdentifier =