[iOS][MF] Enable pull to reset

Similar to pull to refresh, pulling the suggestions to the right will
reset the keyboard and the manual fallback view.

Video: https://drive.google.com/file/d/1QpoiU3YPXdFhLQ_ubzZcyJ7VxVo86Zpv/view?usp=sharing

Bug: 845472, 911142
Change-Id: Ie13322d168dac81288d95a8e10a0bcb5bab59339
Reviewed-on: https://chromium-review.googlesource.com/c/1355188
Commit-Queue: Javier Ernesto Flores Robles <javierrobles@chromium.org>
Reviewed-by: Olivier Robin <olivierrobin@chromium.org>
Reviewed-by: Brian White <bcwhite@chromium.org>
Cr-Commit-Position: refs/heads/master@{#613169}

ios/chrome/browser/autofill/form_input_accessory_view_controller.mm

@@ -6,6 +6,7 @@
 
 #include "base/mac/foundation_util.h"
 #include "base/metrics/histogram_macros.h"
+#include "base/metrics/user_metrics.h"
 #include "components/autofill/core/common/autofill_features.h"
 #import "ios/chrome/browser/autofill/form_input_accessory_view.h"
 #import "ios/chrome/browser/autofill/form_suggestion_view.h"
@@ -23,6 +24,7 @@ CGFloat const kInputAccessoryHeight = 44.0f;
 }  // namespace autofill
 
 @interface FormInputAccessoryViewController () <
+    FormSuggestionViewDelegate,
     ManualFillAccessoryViewControllerDelegate>
 
 // Grey view used as the background of the keyboard to fix
@@ -133,7 +135,7 @@ CGFloat const kInputAccessoryHeight = 44.0f;
 }
 
 - (void)unlockManualFallbackView {
-  [self.formSuggestionView unlockTrailingView];
+  [self.formSuggestionView resetContentInsetAndDelegate];
 }
 
 - (void)lockManualFallbackView {
@@ -141,7 +143,7 @@ CGFloat const kInputAccessoryHeight = 44.0f;
 }
 
 - (void)resetManualFallbackIcons {
-  [self.manualFillAccessoryViewController reset];
+  [self.manualFillAccessoryViewController resetAnimated:YES];
 }
 
 #pragma mark - FormInputAccessoryConsumer
@@ -178,6 +180,7 @@ CGFloat const kInputAccessoryHeight = 44.0f;
   // Create the views if they don't exist already.
   if (!self.formSuggestionView) {
     self.formSuggestionView = [[FormSuggestionView alloc] init];
+    self.formSuggestionView.formSuggestionViewDelegate = self;
   }
 
   [self.formSuggestionView updateClient:suggestionClient
@@ -209,7 +212,7 @@ CGFloat const kInputAccessoryHeight = 44.0f;
 }
 
 - (void)restoreOriginalKeyboardView {
-  [self.manualFillAccessoryViewController reset];
+  [self.manualFillAccessoryViewController resetAnimated:NO];
   [self removeCustomInputAccessoryView];
   [self.keyboardReplacementView removeFromSuperview];
   self.keyboardReplacementView = nil;
@@ -430,4 +433,15 @@ CGFloat const kInputAccessoryHeight = 44.0f;
   [self.manualFillAccessoryViewControllerDelegate passwordButtonPressed:sender];
 }
 
+#pragma mark - FormSuggestionViewDelegate
+
+- (void)formSuggestionViewShouldResetFromPull:
+    (FormSuggestionView*)formSuggestionView {
+  base::RecordAction(base::UserMetricsAction("ManualFallback_ClosePull"));
+  // The pull gesture has the same effect as when the keyboard button is
+  // pressed.
+  [self.manualFillAccessoryViewControllerDelegate keyboardButtonPressed];
+  [self.manualFillAccessoryViewController resetAnimated:YES];
+}
+
 @end

ios/chrome/browser/autofill/form_suggestion_view.h

@@ -9,10 +9,24 @@
 
 @class FormSuggestion;
 @protocol FormSuggestionClient;
+@class FormSuggestionView;
+
+@protocol FormSuggestionViewDelegate <NSObject>
+
+// The view received a long pull in the content direction. The delegate should
+// probably unlock the trailing view and reset to a clean state.
+- (void)formSuggestionViewShouldResetFromPull:
+    (FormSuggestionView*)formSuggestionView;
+
+@end
 
 // A scrollable view for displaying user-selectable autofill form suggestions.
 @interface FormSuggestionView : UIScrollView<UIInputViewAudioFeedback>
 
+// The delegate for FormSuggestionView events.
+@property(nonatomic, weak) id<FormSuggestionViewDelegate>
+    formSuggestionViewDelegate;
+
 // The current suggestions this view is showing.
 @property(nonatomic, readonly) NSArray<FormSuggestion*>* suggestions;
 
@@ -23,8 +37,9 @@
 - (void)updateClient:(id<FormSuggestionClient>)client
          suggestions:(NSArray<FormSuggestion*>*)suggestions;
 
-// Animates the content insets back to zero.
-- (void)unlockTrailingView;
+// Reset content insets back to zero and sets the delegate to nil. Used to stop
+// hearing for the pull gesture to reset and unlock the trailing view.
+- (void)resetContentInsetAndDelegate;
 
 // Animates the content insets so the trailing view is showed as the first
 // thing.

ios/chrome/browser/autofill/form_suggestion_view.mm

@@ -29,7 +29,7 @@ const CGFloat kSuggestionHorizontalMargin = 6;
 
 }  // namespace
 
-@interface FormSuggestionView ()
+@interface FormSuggestionView () <UIScrollViewDelegate>
 
 // The FormSuggestions that are displayed by this view.
 @property(nonatomic) NSArray<FormSuggestion*>* suggestions;
@@ -65,10 +65,8 @@ const CGFloat kSuggestionHorizontalMargin = 6;
   }
 }
 
-- (void)unlockTrailingView {
-  if (!self.superview) {
-    return;
-  }
+- (void)resetContentInsetAndDelegate {
+  self.delegate = nil;
   [UIView animateWithDuration:0.2
                    animations:^{
                      self.contentInset = UIEdgeInsetsZero;
@@ -79,16 +77,18 @@ const CGFloat kSuggestionHorizontalMargin = 6;
   if (!self.superview || !self.trailingView) {
     return;
   }
-
   LayoutOffset layoutOffset = CGRectGetLeadingLayoutOffsetInBoundingRect(
       self.trailingView.frame, {CGPointZero, self.contentSize});
   // Because the way the scroll view is transformed for RTL, the insets don't
   // need to be directed.
   UIEdgeInsets lockedContentInsets = UIEdgeInsetsMake(0, -layoutOffset, 0, 0);
   [UIView animateWithDuration:0.2
-                   animations:^{
-                     self.contentInset = lockedContentInsets;
-                   }];
+      animations:^{
+        self.contentInset = lockedContentInsets;
+      }
+      completion:^(BOOL finished) {
+        self.delegate = self;
+      }];
 }
 
 #pragma mark - UIView
@@ -183,4 +183,14 @@ const CGFloat kSuggestionHorizontalMargin = 6;
   }
 }
 
+- (void)scrollViewDidScroll:(UIScrollView*)scrollView {
+  CGFloat offset = self.contentOffset.x;
+  CGFloat inset = self.contentInset.left;  // Inset is negative when locked.
+  CGFloat diff = offset + inset;
+  if (diff < -55) {
+    [self.formSuggestionViewDelegate
+        formSuggestionViewShouldResetFromPull:self];
+  }
+}
+
 @end

ios/chrome/browser/ui/autofill/form_input_accessory_coordinator.mm

@@ -183,16 +183,18 @@
   [self.formInputAccessoryMediator disableSuggestions];
 }
 
+#pragma mark - FallbackCoordinatorDelegate
+
+- (void)resetAccessoryView {
+  [self.formInputAccessoryViewController resetManualFallbackIcons];
+}
+
 #pragma mark - PasswordCoordinatorDelegate
 
 - (void)openPasswordSettings {
   [self.delegate openPasswordSettings];
 }
 
-- (void)resetAccessoryView {
-  [self.formInputAccessoryViewController resetManualFallbackIcons];
-}
-
 #pragma mark - CardCoordinatorDelegate
 
 - (void)openCardSettings {

ios/chrome/browser/ui/autofill/manual_fill/manual_fill_accessory_view_controller.h

@@ -69,7 +69,7 @@ extern NSString* const AccessoryCreditCardAccessibilityIdentifier;
 
 // Resets to the original state, with the keyboard icon hidden and no icon
 // selected.
-- (void)reset;
+- (void)resetAnimated:(BOOL)animated;
 
 @end
 

ios/chrome/browser/ui/autofill/manual_fill/manual_fill_accessory_view_controller.mm

@@ -75,10 +75,16 @@ static NSTimeInterval MFAnimationDuration = 0.2;
   return self;
 }
 
-- (void)reset {
-  [self resetTintColors];
-  self.keyboardButton.hidden = YES;
-  self.keyboardButton.alpha = 0.0;
+- (void)resetAnimated:(BOOL)animated {
+  [UIView animateWithDuration:animated ? MFAnimationDuration : 0
+                   animations:^{
+                     [self resetTintColors];
+                     // Workaround the |hidden| property in stacked views.
+                     if (!self.keyboardButton.hidden) {
+                       self.keyboardButton.hidden = YES;
+                       self.keyboardButton.alpha = 0.0;
+                     }
+                   }];
 }
 
 #pragma mark - Setters
@@ -221,11 +227,15 @@ static NSTimeInterval MFAnimationDuration = 0.2;
 - (void)animateKeyboardButtonHidden:(BOOL)hidden {
   [UIView animateWithDuration:MFAnimationDuration
                    animations:^{
+                     // Workaround setting more than once the |hidden| property
+                     // in stacked views.
+                     if (self.keyboardButton.hidden != hidden) {
+                       self.keyboardButton.hidden = hidden;
+                     }
+
                      if (hidden) {
-                       self.keyboardButton.hidden = YES;
                        self.keyboardButton.alpha = 0.0;
                      } else {
-                       self.keyboardButton.hidden = NO;
                        self.keyboardButton.alpha = 1.0;
                      }
                    }];

tools/metrics/actions/actions.xml

@@ -10143,6 +10143,14 @@ should be able to be added at any place in this file.
   </description>
 </action>
 
+<action name="ManualFallback_ClosePull">
+  <owner>javierrobles@chromium.org</owner>
+  <description>
+    The user closed the Manual Fallback view by pulling. This happens when the
+    user pulls enough to the right, similar to &quot;pull to refresh&quot;.
+  </description>
+</action>
+
 <action name="ManualFallback_CreditCard_OpenManageCreditCard">
   <owner>javierrobles@chromium.org</owner>
   <description>