Reuse ConfirmationAlertViewController for QRGeneratorViewController

Also, allow usage of fixed size image to prevent scaling-up the QR code
(it becomes too big to be scanned effectively).

Sample:
https://screenshot.googleplex.com/xYWmsrTzZpD.png

Bug: 1064990
Change-Id: Ibd1e7f5f1149e436929ca8c33b1dae7807172411
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2153391
Commit-Queue: Sebastien Lalancette <seblalancette@chromium.org>
Reviewed-by: Javier Ernesto Flores Robles <javierrobles@chromium.org>
Reviewed-by: Mark Cogan <marq@chromium.org>
Cr-Commit-Position: refs/heads/master@{#761167}

ios/chrome/app/strings/ios_strings.grd

@@ -1609,6 +1609,9 @@ Handoff must also be enabled in the General section of Settings, and your device
       <message name="IDS_IOS_TOGGLE_SETTING_SWITCH_ACCESSIBILITY_HINT" desc="Action hint for any switch in settings. This is spoken by VoiceOver. [iOS only]">
         Double tap to toggle setting
       </message>
+      <message name="IDS_IOS_SHARE_BUTTON_LABEL" desc="Label of a button which will initiate a share flow. [iOS only]">
+        Share...
+      </message>
       <message name="IDS_IOS_SHARE_EMAIL_COMPLETE" desc="Message shown when email share has been sent. [Length: Unknown. Keep it short.] [iOS only]">
         Mail sent.
       </message>

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

@@ -12,9 +12,10 @@ source_set("ui") {
   ]
   deps = [
     "//base",
+    "//ios/chrome/app/strings",
     "//ios/chrome/browser/ui/commands",
     "//ios/chrome/browser/ui/util",
-    "//ios/chrome/common/ui/colors",
+    "//ios/chrome/common/ui/confirmation_alert",
     "//ui/base",
     "//url:url",
   ]
@@ -36,6 +37,7 @@ source_set("qr_generator") {
     "//ios/chrome/browser/main:public",
     "//ios/chrome/browser/ui/commands",
     "//ios/chrome/browser/ui/coordinators:chrome_coordinators",
+    "//ios/chrome/common/ui/confirmation_alert",
     "//net",
   ]
 }
@@ -44,15 +46,18 @@ source_set("unit_tests") {
   configs += [ "//build/config/compiler:enable_arc" ]
   testonly = true
   sources = [
+    "qr_generator_coordinator_unittest.mm",
     "qr_generator_util_unittest.mm",
-    "qr_generator_view_controller_unittest.mm",
   ]
   deps = [
+    ":qr_generator",
     ":ui",
     "//base",
     "//base/test:test_support",
+    "//ios/chrome/browser/main:test_support",
     "//ios/chrome/browser/ui/commands",
-    "//ios/chrome/common/ui/colors",
+    "//ios/chrome/common/ui/confirmation_alert",
+    "//ios/chrome/test:test_support",
     "//ios/chrome/test/fakes",
     "//ios/web",
     "//ios/web/public/test",

ios/chrome/browser/ui/qr_generator/qr_generator_coordinator.mm

@@ -9,27 +9,23 @@
 #import "ios/chrome/browser/ui/commands/command_dispatcher.h"
 #import "ios/chrome/browser/ui/commands/qr_generation_commands.h"
 #import "ios/chrome/browser/ui/qr_generator/qr_generator_view_controller.h"
+#import "ios/chrome/common/ui/confirmation_alert/confirmation_alert_action_handler.h"
 #import "net/base/mac/url_conversions.h"
 
 #if !defined(__has_feature) || !__has_feature(objc_arc)
 #error "This file requires ARC support."
 #endif
 
-@interface QRGeneratorCoordinator () {
+@interface QRGeneratorCoordinator () <ConfirmationAlertActionHandler> {
   // URL of a page to generate a QR code for.
   GURL _URL;
 }
 
-// To be used to dispatch commands to the browser.
-@property(nonatomic, strong) CommandDispatcher* dispatcher;
-
-// Main view controller which will be the parent, or ancestor, of other
-// view controllers related to this feature.
-@property(nonatomic, strong) UINavigationController* viewController;
+// To be used to handle behaviors that go outside the scope of this class.
+@property(nonatomic, strong) id<QRGenerationCommands> handler;
 
 // View controller used to display the QR code and actions.
-@property(nonatomic, strong)
-    QRGeneratorViewController* qrGeneratorViewController;
+@property(nonatomic, strong) QRGeneratorViewController* viewController;
 
 // Title of a page to generate a QR code for.
 @property(nonatomic, copy) NSString* title;
@@ -53,17 +49,15 @@
 #pragma mark - Chrome Coordinator
 
 - (void)start {
-  self.dispatcher = self.browser->GetCommandDispatcher();
-
-  self.qrGeneratorViewController = [[QRGeneratorViewController alloc] init];
-  self.qrGeneratorViewController.handler =
-      HandlerForProtocol(self.dispatcher, QRGenerationCommands);
+  self.handler = HandlerForProtocol(self.browser->GetCommandDispatcher(),
+                                    QRGenerationCommands);
 
-  [self.qrGeneratorViewController setPageURL:net::NSURLWithGURL(_URL)];
+  self.viewController = [[QRGeneratorViewController alloc] init];
 
-  self.viewController = [[UINavigationController alloc]
-      initWithRootViewController:self.qrGeneratorViewController];
   [self.viewController setModalPresentationStyle:UIModalPresentationFormSheet];
+  [self.viewController setPageURL:net::NSURLWithGURL(_URL)];
+  [self.viewController setTitleString:self.title];
+  [self.viewController setActionHandler:self];
 
   [self.baseViewController presentViewController:self.viewController
                                         animated:YES
@@ -72,14 +66,26 @@
 }
 
 - (void)stop {
-  [self.viewController.presentingViewController
-      dismissViewControllerAnimated:YES
-                         completion:nil];
-
-  self.qrGeneratorViewController = nil;
+  [self.viewController dismissViewControllerAnimated:YES completion:nil];
   self.viewController = nil;
 
   [super stop];
 }
 
+#pragma mark - ConfirmationAlertActionHandler
+
+- (void)confirmationAlertDone {
+  [self.handler hideQRCode];
+}
+
+- (void)confirmationAlertPrimaryAction {
+  // No-op.
+  // TODO crbug.com/1064990: Add sharing action.
+}
+
+- (void)confirmationAlertLearnMoreAction {
+  // No-op.
+  // TODO crbug.com/1064990: Add learn more behavior.
+}
+
 @end

ios/chrome/browser/ui/qr_generator/qr_generator_coordinator_unittest.mm

+// Copyright 2020 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/qr_generator/qr_generator_coordinator.h"
+
+#import "base/mac/foundation_util.h"
+#import "base/test/task_environment.h"
+#import "ios/chrome/browser/main/test_browser.h"
+#import "ios/chrome/browser/ui/commands/command_dispatcher.h"
+#import "ios/chrome/browser/ui/commands/qr_generation_commands.h"
+#import "ios/chrome/browser/ui/qr_generator/qr_generator_view_controller.h"
+#import "ios/chrome/common/ui/confirmation_alert/confirmation_alert_action_handler.h"
+#import "ios/chrome/test/scoped_key_window.h"
+#include "testing/platform_test.h"
+#import "third_party/ocmock/OCMock/OCMock.h"
+#include "url/gurl.h"
+
+#if !defined(__has_feature) || !__has_feature(objc_arc)
+#error "This file requires ARC support."
+#endif
+
+class QRGeneratorCoordinatorTest : public PlatformTest {
+ protected:
+  QRGeneratorCoordinatorTest() : browser_(std::make_unique<TestBrowser>()) {
+    base_view_controller_ = [[UIViewController alloc] init];
+    [scoped_key_window_.Get() setRootViewController:base_view_controller_];
+  }
+
+  void SetUp() override {
+    mock_qr_generation_commands_handler_ =
+        OCMStrictProtocolMock(@protocol(QRGenerationCommands));
+
+    [browser_->GetCommandDispatcher()
+        startDispatchingToTarget:mock_qr_generation_commands_handler_
+                     forProtocol:@protocol(QRGenerationCommands)];
+  }
+
+  base::test::TaskEnvironment task_environment_;
+  id mock_qr_generation_commands_handler_;
+  std::unique_ptr<TestBrowser> browser_;
+  ScopedKeyWindow scoped_key_window_;
+  UIViewController* base_view_controller_;
+};
+
+// Tests that a Done button gets added to the navigation bar, and its action
+// dispatches the right command.
+TEST_F(QRGeneratorCoordinatorTest, Done_DispatchesCommand) {
+  // Set-up mocked handler.
+  [[mock_qr_generation_commands_handler_ expect] hideQRCode];
+
+  // Create and start coordinator.
+  QRGeneratorCoordinator* coordinator = [[QRGeneratorCoordinator alloc]
+      initWithBaseViewController:base_view_controller_
+                         browser:browser_.get()
+                           title:@"Does not matter"
+                             URL:GURL()];
+
+  ASSERT_EQ(base_view_controller_, coordinator.baseViewController);
+  ASSERT_FALSE(base_view_controller_.presentedViewController);
+
+  [coordinator start];
+
+  ASSERT_TRUE(base_view_controller_.presentedViewController);
+  ASSERT_TRUE([base_view_controller_.presentedViewController
+      isKindOfClass:[QRGeneratorViewController class]]);
+
+  QRGeneratorViewController* viewController =
+      base::mac::ObjCCastStrict<QRGeneratorViewController>(
+          base_view_controller_.presentedViewController);
+
+  // Mimick click on done button.
+  [viewController.actionHandler confirmationAlertDone];
+
+  // Callback should've gotten invoked.
+  [mock_qr_generation_commands_handler_ verify];
+}

ios/chrome/browser/ui/qr_generator/qr_generator_view_controller.h

@@ -6,14 +6,12 @@
 #define IOS_CHROME_BROWSER_UI_QR_GENERATOR_QR_GENERATOR_VIEW_CONTROLLER_H_
 
 #import "ios/chrome/browser/ui/commands/qr_generation_commands.h"
+#import "ios/chrome/common/ui/confirmation_alert/confirmation_alert_view_controller.h"
 
 #import <UIKit/UIKit.h>
 
 // View controller that displays a QR code representing a given website.
-@interface QRGeneratorViewController : UIViewController
-
-// Command handler for communicating with other components of the app.
-@property(nonatomic, weak) id<QRGenerationCommands> handler;
+@interface QRGeneratorViewController : ConfirmationAlertViewController
 
 // URL of the page to generate a QR code for.
 @property(nonatomic, copy) NSURL* pageURL;

ios/chrome/browser/ui/qr_generator/qr_generator_view_controller.mm

@@ -6,121 +6,43 @@
 #import "ios/chrome/browser/ui/qr_generator/qr_generator_view_controller.h"
 
 #import "ios/chrome/browser/ui/qr_generator/qr_generator_util.h"
-#import "ios/chrome/browser/ui/util/uikit_ui_util.h"
-#import "ios/chrome/common/ui/colors/UIColor+cr_semantic_colors.h"
+#include "ios/chrome/grit/ios_strings.h"
+#include "ui/base/l10n/l10n_util_mac.h"
 
 #if !defined(__has_feature) || !__has_feature(objc_arc)
 #error "This file requires ARC support."
 #endif
 
-NSString* const kQRGeneratorDoneButtonId = @"kQRGeneratorDoneButtonId";
-
 // Height and width of the QR code image, in points.
 const CGFloat kQRCodeImageSize = 200.0;
 
 @interface QRGeneratorViewController ()
 
-// View for the QR code image.
-@property(nonatomic, strong) UIImageView* qrCodeView;
-
-// Orientation-specific constraints.
-@property(nonatomic, strong)
-    NSArray<NSLayoutConstraint*>* compactHeightConstraints;
-@property(nonatomic, strong)
-    NSArray<NSLayoutConstraint*>* regularHeightConstraints;
-
 @end
 
 @implementation QRGeneratorViewController
 
 #pragma mark - UIViewController
 
-- (void)viewDidLoad {
-  [super viewDidLoad];
-
-  [self setUpNavigation];
-
-  self.qrCodeView = [self createQRCodeImageView];
-
-  [self.view addSubview:self.qrCodeView];
-
-  [self setupConstraints];
-}
+- (void)loadView {
+  self.image = [self createQRCodeImage];
+  self.imageHasFixedSize = YES;
 
-- (void)traitCollectionDidChange:(UITraitCollection*)previousTraitCollection {
-  [super traitCollectionDidChange:previousTraitCollection];
+  self.subtitleString = [self.pageURL host];
 
-  if (previousTraitCollection.verticalSizeClass !=
-      self.traitCollection.verticalSizeClass) {
-    [self updateViewConstraints];
-  }
-}
+  self.primaryActionAvailable = YES;
+  self.primaryActionString = l10n_util::GetNSString(IDS_IOS_SHARE_BUTTON_LABEL);
 
-- (void)updateViewConstraints {
-  // Check if we're in landscape mode or not.
-  if (IsCompactHeight(self)) {
-    [NSLayoutConstraint deactivateConstraints:self.regularHeightConstraints];
-    [NSLayoutConstraint activateConstraints:self.compactHeightConstraints];
-  } else {
-    [NSLayoutConstraint deactivateConstraints:self.compactHeightConstraints];
-    [NSLayoutConstraint activateConstraints:self.regularHeightConstraints];
-  }
-  [super updateViewConstraints];
+  self.helpButtonAvailable = YES;
+  [super loadView];
 }
 
 #pragma mark - Private Methods
 
-- (void)setUpNavigation {
-  // Set shadowImage to an empty image to remove the separator between the
-  // navigation bar and the main content.
-  self.navigationController.navigationBar.shadowImage = [[UIImage alloc] init];
-
-  // Set background color.
-  [self.navigationController.navigationBar setTranslucent:NO];
-  [self.navigationController.navigationBar
-      setBarTintColor:UIColor.cr_systemBackgroundColor];
-  [self.navigationController.view
-      setBackgroundColor:UIColor.cr_systemBackgroundColor];
-
-  // Add a Done button to the navigation bar.
-  UIBarButtonItem* doneButton = [[UIBarButtonItem alloc]
-      initWithBarButtonSystemItem:UIBarButtonSystemItemDone
-                           target:self.handler
-                           action:@selector(hideQRCode)];
-  doneButton.accessibilityIdentifier = kQRGeneratorDoneButtonId;
-  self.navigationItem.rightBarButtonItem = doneButton;
-}
-
-- (UIImageView*)createQRCodeImageView {
+- (UIImage*)createQRCodeImage {
   NSData* urlData =
       [[self.pageURL absoluteString] dataUsingEncoding:NSUTF8StringEncoding];
-  UIImage* qrCodeImage = GenerateQRCode(urlData, kQRCodeImageSize);
-
-  UIImageView* qrCodeView = [[UIImageView alloc] initWithImage:qrCodeImage];
-  qrCodeView.translatesAutoresizingMaskIntoConstraints = NO;
-  return qrCodeView;
-}
-
-- (void)setupConstraints {
-  // Set-up orientation-specific constraints.
-  self.compactHeightConstraints = @[
-    [self.qrCodeView.topAnchor constraintEqualToAnchor:self.view.topAnchor
-                                              constant:20.0],
-  ];
-  self.regularHeightConstraints = @[
-    [self.qrCodeView.topAnchor constraintEqualToAnchor:self.view.topAnchor
-                                              constant:60.0],
-  ];
-
-  // Activate the right orientation-specific constraint.
-  [self updateViewConstraints];
-
-  // Activate common constraints.
-  NSArray* commonConstraints = @[
-    [self.qrCodeView.centerXAnchor
-        constraintEqualToAnchor:self.view.centerXAnchor],
-  ];
-  [NSLayoutConstraint activateConstraints:commonConstraints];
+  return GenerateQRCode(urlData, kQRCodeImageSize);
 }
 
 @end

ios/chrome/browser/ui/qr_generator/qr_generator_view_controller_unittest.mm

-// Copyright 2020 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/qr_generator/qr_generator_view_controller.h"
-
-#import "ios/chrome/browser/ui/commands/qr_generation_commands.h"
-#import "ios/chrome/common/ui/colors/UIColor+cr_semantic_colors.h"
-#include "testing/platform_test.h"
-#import "third_party/ocmock/OCMock/OCMock.h"
-#include "url/gurl.h"
-
-#if !defined(__has_feature) || !__has_feature(objc_arc)
-#error "This file requires ARC support."
-#endif
-
-class QRGeneratorViewControllerTest : public PlatformTest {
- public:
-  QRGeneratorViewControllerTest()
-      : view_controller_([[QRGeneratorViewController alloc] init]) {}
-
- protected:
-  void SetUp() override { [view_controller_ loadViewIfNeeded]; }
-
-  QRGeneratorViewController* view_controller_;
-
- private:
-  DISALLOW_COPY_AND_ASSIGN(QRGeneratorViewControllerTest);
-};
-
-// Tests that a Done button gets added to the navigation bar, and its action
-// dispatches the right command.
-TEST_F(QRGeneratorViewControllerTest, DoneButton_DispatchesCommand) {
-  // Set-up mocked handler.
-  id mockedHandler = OCMStrictProtocolMock(@protocol(QRGenerationCommands));
-  [[mockedHandler expect] hideQRCode];
-  [view_controller_ setHandler:mockedHandler];
-
-  // Set-up mocked navigation item.
-  __block UIBarButtonItem* capturedButton;
-  id navItemMock = OCMStrictClassMock([UINavigationItem class]);
-  [[navItemMock expect]
-      setRightBarButtonItem:[OCMArg
-                                checkWithBlock:^BOOL(UIBarButtonItem* button) {
-                                  capturedButton = button;
-                                  return !!capturedButton;
-                                }]];
-
-  id vcPartialMock = OCMPartialMock(view_controller_);
-  OCMStub([vcPartialMock navigationItem]).andReturn(navItemMock);
-
-  [view_controller_ viewDidLoad];
-
-  // Button should've been given to the navigationItem.
-  [navItemMock verify];
-
-  // Simulate a click on the button.
-  [[UIApplication sharedApplication] sendAction:capturedButton.action
-                                             to:capturedButton.target
-                                           from:nil
-                                       forEvent:nil];
-
-  // Callback should've gotten invoked.
-  [mockedHandler verify];
-}

ios/chrome/common/ui/confirmation_alert/confirmation_alert_view_controller.h

@@ -36,6 +36,9 @@ extern NSString* const kConfirmationAlertPrimaryActionAccessibilityIdentifier;
 // The image. Must be set before the view is loaded.
 @property(nonatomic, strong) UIImage* image;
 
+// Value to determine whether or not the image's size should be scaled.
+@property(nonatomic) BOOL imageHasFixedSize;
+
 // Controls if there is a help button in the view. Must be set before the
 // view is loaded.
 @property(nonatomic) BOOL helpButtonAvailable;

ios/chrome/common/ui/confirmation_alert/confirmation_alert_view_controller.mm

@@ -146,26 +146,33 @@ constexpr CGFloat kSafeAreaMultiplier = 0.8;
     self.primaryActionButton = primaryActionButton;
   }
 
-  // Constraing the image to the scroll view size and its aspect ratio.
-  [self.imageView
-      setContentCompressionResistancePriority:UILayoutPriorityDefaultLow
-                                      forAxis:UILayoutConstraintAxisHorizontal];
-  [self.imageView
-      setContentCompressionResistancePriority:UILayoutPriorityDefaultLow
-                                      forAxis:UILayoutConstraintAxisVertical];
-  CGFloat imageAspectRatio =
-      self.imageView.image.size.width / self.imageView.image.size.height;
   self.scrollViewBottomVerticalConstraint = [scrollView.bottomAnchor
       constraintLessThanOrEqualToAnchor:scrollViewBottomAnchor];
 
   [NSLayoutConstraint activateConstraints:@[
-    [self.imageView.widthAnchor
-        constraintEqualToAnchor:self.imageView.heightAnchor
-                     multiplier:imageAspectRatio],
     [scrollView.topAnchor
         constraintGreaterThanOrEqualToAnchor:topToolbar.bottomAnchor],
     self.scrollViewBottomVerticalConstraint,
   ]];
+
+  if (!self.imageHasFixedSize) {
+    // Constrain the image to the scroll view size and its aspect ratio.
+    [self.imageView
+        setContentCompressionResistancePriority:UILayoutPriorityDefaultLow
+                                        forAxis:
+                                            UILayoutConstraintAxisHorizontal];
+    [self.imageView
+        setContentCompressionResistancePriority:UILayoutPriorityDefaultLow
+                                        forAxis:UILayoutConstraintAxisVertical];
+    CGFloat imageAspectRatio =
+        self.imageView.image.size.width / self.imageView.image.size.height;
+
+    [NSLayoutConstraint activateConstraints:@[
+      [self.imageView.widthAnchor
+          constraintEqualToAnchor:self.imageView.heightAnchor
+                       multiplier:imageAspectRatio],
+    ]];
+  }
 }
 
 - (void)traitCollectionDidChange:(UITraitCollection*)previousTraitCollection {
@@ -343,8 +350,14 @@ constexpr CGFloat kSafeAreaMultiplier = 0.8;
       [[UIStackView alloc] initWithArrangedSubviews:subviews];
   [stackView setCustomSpacing:kStackViewSpacingAfterIllustration
                     afterView:self.imageView];
+
+  if (self.imageHasFixedSize) {
+    stackView.alignment = UIStackViewAlignmentCenter;
+  } else {
+    stackView.alignment = UIStackViewAlignmentFill;
+  }
+
   stackView.axis = UILayoutConstraintAxisVertical;
-  stackView.alignment = UIStackViewAlignmentFill;
   stackView.translatesAutoresizingMaskIntoConstraints = NO;
   stackView.spacing = kStackViewSpacing;
   return stackView;