Refactored notification rationale dialog as a bottom sheet

Android T+ requires apps to request for notification permission.
Chrome does this currently on first startup, and it shows a rationale
dialog before the OS prompt to educate users of the usefulness of
notifications.

Per UX advice this UI should be displayed as a bottom sheet instead of
a dialog. This CL introduces a bottom sheet that contains the same
UI as the existing rationale dialog. It's behind a flag exposed on
chrome://flags.

It also removes an alternative set of strings that were used when experimenting with this UI.

Bottomsheet screenshot:
https://screenshot.googleplex.com/84j6m6brZBz6uSp
HSV:
https://hsv.googleplex.com/6181362051579904

Bug: 1361424
Change-Id: I70b0d79b71643adc99affeeff264e19d443ce222
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/3896995
Commit-Queue: Salvador Guerrero Ramos <salg@google.com>
Reviewed-by: Justin DeWitt <dewittj@chromium.org>
Reviewed-by: Shakti Sahu <shaktisahu@chromium.org>
Cr-Commit-Position: refs/heads/main@{#1095798}

chrome/android/java/src/org/chromium/chrome/browser/tabbed_mode/TabbedRootUiCoordinator.java

@@ -66,6 +66,8 @@
 import org.chromium.chrome.browser.multiwindow.MultiWindowUtils;
 import org.chromium.chrome.browser.night_mode.WebContentsDarkModeMessageController;
 import org.chromium.chrome.browser.notifications.permissions.NotificationPermissionController;
+import org.chromium.chrome.browser.notifications.permissions.NotificationPermissionController.RationaleDelegate;
+import org.chromium.chrome.browser.notifications.permissions.NotificationPermissionRationaleBottomSheet;
 import org.chromium.chrome.browser.notifications.permissions.NotificationPermissionRationaleDialogController;
 import org.chromium.chrome.browser.ntp.NewTabPageLaunchOrigin;
 import org.chromium.chrome.browser.ntp.NewTabPageUtils;
@@ -676,11 +678,22 @@ mActivity, new SettingsLauncherImpl(),
         }
 
         if (!didTriggerPromo) {
-            mNotificationPermissionController = new NotificationPermissionController(mWindowAndroid,
-                    new NotificationPermissionRationaleDialogController(
-                            mActivity, mModalDialogManagerSupplier.get()));
+            RationaleDelegate rationaleUIDelegate;
+
+            if (NotificationPermissionController.shouldUseBottomSheetRationaleUi()) {
+                rationaleUIDelegate = new NotificationPermissionRationaleBottomSheet(
+                        mActivity, getBottomSheetController());
+            } else {
+                rationaleUIDelegate = new NotificationPermissionRationaleDialogController(
+                        mActivity, mModalDialogManagerSupplier.get());
+            }
+
+            mNotificationPermissionController =
+                    new NotificationPermissionController(mWindowAndroid, rationaleUIDelegate);
+
             NotificationPermissionController.attach(
                     mWindowAndroid, mNotificationPermissionController);
+
             didTriggerPromo = mNotificationPermissionController.requestPermissionIfNeeded(
                     false /* contextual */);
         }

chrome/browser/about_flags.cc

@@ -2169,31 +2169,18 @@ const FeatureEntry::FeatureVariation kFeatureNotificationGuideVariations[] = {
      std::size(kFeatureNotificationGuide_default_browser), nullptr},
 };
 
-const FeatureEntry::FeatureParam
-    kNotificationPermissionRationale_show_dialog_next_start_text_variant[] = {
-        {"always_show_rationale_before_requesting_permission", "true"},
-        {"notification_permission_dialog_text_variant_2", "true"},
-        {"permission_request_interval_days", "0"},
-};
-
 const FeatureEntry::FeatureParam
     kNotificationPermissionRationale_show_dialog_next_start[] = {
         {"always_show_rationale_before_requesting_permission", "true"},
-        {"notification_permission_dialog_text_variant_2", "false"},
         {"permission_request_interval_days", "0"},
 };
 
 const FeatureEntry::FeatureVariation
     kNotificationPermissionRationaleVariations[] = {
-        {"- Show rationale dialog on next startup",
+        {"- Show rationale UI on next startup",
          kNotificationPermissionRationale_show_dialog_next_start,
          std::size(kNotificationPermissionRationale_show_dialog_next_start),
          nullptr},
-        {"- Show rationale dialog on next startup - alternative copy",
-         kNotificationPermissionRationale_show_dialog_next_start_text_variant,
-         std::size(
-             kNotificationPermissionRationale_show_dialog_next_start_text_variant),
-         nullptr},
 };
 
 const FeatureEntry::FeatureParam kWebFeed_accelerator[] = {
@@ -4446,6 +4433,11 @@ const FeatureEntry kFeatureEntries[] = {
          chrome::android::kNotificationPermissionVariant,
          kNotificationPermissionRationaleVariations,
          "NotificationPermissionVariant")},
+    {"notification-permission-rationale-bottom-sheet",
+     flag_descriptions::kNotificationPermissionRationaleBottomSheetName,
+     flag_descriptions::kNotificationPermissionRationaleBottomSheetDescription,
+     kOsAndroid,
+     FEATURE_VALUE_TYPE(chrome::android::kNotificationPermissionBottomSheet)},
     {"feature-notification-guide-skip-check-for-low-engaged-users",
      flag_descriptions::
          kFeatureNotificationGuideSkipCheckForLowEngagedUsersName,

chrome/browser/flag-metadata.json

@@ -4864,10 +4864,15 @@
     ],
     "expiry_milestone": 115
   },
+  {
+    "name": "notification-permission-rationale-bottom-sheet",
+    "owners": ["shaktisahu", "salg"],
+    "expiry_milestone": 114
+  },
   {
     "name": "notification-permission-rationale-dialog",
     "owners": ["shaktisahu", "salg"],
-    "expiry_milestone": 110
+    "expiry_milestone": 114
   },
   {
     "name": "notification-scheduler",

chrome/browser/flag_descriptions.cc

@@ -3750,6 +3750,13 @@ const char kNotificationPermissionRationaleDescription[] =
     "Configure the dialog shown before requesting notification permission. "
     "Only works with builds targeting Android T.";
 
+const char kNotificationPermissionRationaleBottomSheetName[] =
+    "Notification Permission Rationale Bottom Sheet UI";
+const char kNotificationPermissionRationaleBottomSheetDescription[] =
+    "Enable the alternative bottom sheet UI for the notification permission "
+    "flow. "
+    "Only works with builds targeting Android T+.";
+
 const char kOfflinePagesLivePageSharingName[] =
     "Enables live page sharing of offline pages";
 const char kOfflinePagesLivePageSharingDescription[] =

chrome/browser/flag_descriptions.h

@@ -2150,6 +2150,9 @@ extern const char kNetworkServiceInProcessDescription[];
 extern const char kNotificationPermissionRationaleName[];
 extern const char kNotificationPermissionRationaleDescription[];
 
+extern const char kNotificationPermissionRationaleBottomSheetName[];
+extern const char kNotificationPermissionRationaleBottomSheetDescription[];
+
 extern const char kOfflinePagesLivePageSharingName[];
 extern const char kOfflinePagesLivePageSharingDescription[];
 

chrome/browser/flags/android/chrome_feature_list.cc

@@ -235,6 +235,7 @@ const base::Feature* const kFeaturesExposedToJava[] = {
     &kLensCameraAssistedSearch,
     &kLensOnQuickActionSearchWidget,
     &kNotificationPermissionVariant,
+    &kNotificationPermissionBottomSheet,
     &kPageAnnotationsService,
     &kBookmarksImprovedSaveFlow,
     &kBookmarksRefresh,
@@ -725,6 +726,10 @@ BASE_FEATURE(kNotificationPermissionVariant,
              "NotificationPermissionVariant",
              base::FEATURE_DISABLED_BY_DEFAULT);
 
+BASE_FEATURE(kNotificationPermissionBottomSheet,
+             "NotificationPermissionBottomSheet",
+             base::FEATURE_DISABLED_BY_DEFAULT);
+
 BASE_FEATURE(kInstanceSwitcher,
              "InstanceSwitcher",
              base::FEATURE_ENABLED_BY_DEFAULT);

chrome/browser/flags/android/chrome_feature_list.h

@@ -101,6 +101,7 @@ BASE_DECLARE_FEATURE(kLensCameraAssistedSearch);
 BASE_DECLARE_FEATURE(kLensOnQuickActionSearchWidget);
 BASE_DECLARE_FEATURE(kLocationBarModelOptimizations);
 BASE_DECLARE_FEATURE(kNotificationPermissionVariant);
+BASE_DECLARE_FEATURE(kNotificationPermissionBottomSheet);
 BASE_DECLARE_FEATURE(kOmahaMinSdkVersionAndroid);
 BASE_DECLARE_FEATURE(kOmniboxModernizeVisualUpdate);
 BASE_DECLARE_FEATURE(kOptimizeGeolocationHeaderGeneration);

chrome/browser/flags/android/java/src/org/chromium/chrome/browser/flags/ChromeFeatureList.java

@@ -365,6 +365,8 @@ public static boolean getFieldTrialParamByFeatureAsBoolean(
     public static final String METRICS_SETTINGS_ANDROID = "MetricsSettingsAndroid";
     public static final String MODAL_PERMISSION_DIALOG_VIEW = "ModalPermissionDialogView";
     public static final String NOTIFICATION_PERMISSION_VARIANT = "NotificationPermissionVariant";
+    public static final String NOTIFICATION_PERMISSION_BOTTOM_SHEET =
+            "NotificationPermissionBottomSheet";
     public static final String OFFLINE_PAGES_DESCRIPTIVE_FAIL_STATUS =
             "OfflinePagesDescriptiveFailStatus";
     public static final String OFFLINE_PAGES_DESCRIPTIVE_PENDING_STATUS =

chrome/browser/notifications/BUILD.gn

@@ -59,6 +59,7 @@ if (is_android) {
       "android/java/src/org/chromium/chrome/browser/notifications/channels/SiteChannelsManager.java",
       "android/java/src/org/chromium/chrome/browser/notifications/permissions/NotificationPermissionChangeReceiver.java",
       "android/java/src/org/chromium/chrome/browser/notifications/permissions/NotificationPermissionController.java",
+      "android/java/src/org/chromium/chrome/browser/notifications/permissions/NotificationPermissionRationaleBottomSheet.java",
       "android/java/src/org/chromium/chrome/browser/notifications/permissions/NotificationPermissionRationaleDialogController.java",
     ]
 
@@ -70,6 +71,7 @@ if (is_android) {
       "//chrome/browser/offline_pages/android:java",
       "//chrome/browser/preferences:java",
       "//chrome/browser/profiles/android:java",
+      "//components/browser_ui/bottomsheet/android:java",
       "//components/browser_ui/notifications/android:java",
       "//components/browser_ui/settings/android:java",
       "//components/browser_ui/site_settings/android:java",
@@ -112,6 +114,7 @@ if (is_android) {
       "android/java/src/org/chromium/chrome/browser/notifications/channels/ChromeChannelDefinitionsTest.java",
       "android/java/src/org/chromium/chrome/browser/notifications/permissions/NotificationPermissionChangeReceiverTest.java",
       "android/java/src/org/chromium/chrome/browser/notifications/permissions/NotificationPermissionControllerTest.java",
+      "android/java/src/org/chromium/chrome/browser/notifications/permissions/NotificationPermissionRationaleBottomSheetTest.java",
       "android/java/src/org/chromium/chrome/browser/notifications/permissions/NotificationPermissionRationaleDialogControllerTest.java",
       "android/java/src/org/chromium/chrome/browser/notifications/permissions/TestRationaleDelegate.java",
     ]
@@ -124,6 +127,7 @@ if (is_android) {
       "//chrome/browser/flags:java",
       "//chrome/browser/preferences:java",
       "//chrome/test/android:chrome_java_unit_test_support",
+      "//components/browser_ui/bottomsheet/android:java",
       "//components/browser_ui/notifications/android:java",
       "//components/embedder_support/android:junit_test_support",
       "//components/url_formatter/android:url_formatter_java",
@@ -175,6 +179,7 @@ if (is_android) {
     sources = [
       "android/java/res/drawable-ldrtl/notification_permission_rationale_dialog_header.xml",
       "android/java/res/drawable/notification_permission_rationale_dialog_header.xml",
+      "android/java/res/layout/notification_permission_rationale_bottom_sheet.xml",
       "android/java/res/layout/notification_permission_rationale_dialog.xml",
       "android/java/res/values-night/colors.xml",
       "android/java/res/values/colors.xml",

chrome/browser/notifications/android/java/res/layout/notification_permission_rationale_bottom_sheet.xml

@@ -0,0 +1,53 @@
+<?xml version="1.0" encoding="utf-8"?>
+<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
+    xmlns:app="http://schemas.android.com/apk/res-auto"
+    android:layout_width="wrap_content"
+    android:layout_height="wrap_content"
+    android:layout_gravity="center"
+    android:orientation="vertical">
+
+  <ImageView
+      android:layout_width="250dp"
+      android:layout_height="0dp"
+      android:layout_weight="1"
+      android:layout_marginVertical="24dp"
+      android:layout_gravity="center_horizontal"
+      android:importantForAccessibility="no"
+      android:src="@drawable/notification_permission_rationale_dialog_header"
+      app:srcCompat="@drawable/notification_permission_rationale_dialog_header" />
+
+  <TextView
+      android:id="@+id/notification_permission_rationale_title"
+      android:layout_width="wrap_content"
+      android:layout_height="wrap_content"
+      android:layout_marginHorizontal="16dp"
+      android:text="@string/notification_permission_rationale_dialog_title"
+      android:textAppearance="@style/TextAppearance.Headline.Primary" />
+
+  <TextView
+      android:id="@+id/notification_permission_rationale_message"
+      android:layout_width="wrap_content"
+      android:layout_height="wrap_content"
+      android:layout_marginTop="12dp"
+      android:layout_marginHorizontal="16dp"
+      android:text="@string/notification_permission_rationale_dialog_message"
+      android:textAppearance="@style/TextAppearance.TextMedium.Primary" />
+
+  <org.chromium.ui.widget.ButtonCompat
+      android:layout_width="match_parent"
+      android:layout_height="wrap_content"
+      android:id="@+id/notification_permission_rationale_positive_button"
+      android:layout_marginTop="28dp"
+      android:layout_marginHorizontal="16dp"
+      style="@style/FilledButton.Flat"
+      android:text="@string/notification_permission_rationale_accept_button_text"/>
+
+  <org.chromium.ui.widget.ButtonCompat
+      android:layout_width="match_parent"
+      android:layout_height="wrap_content"
+      android:id="@+id/notification_permission_rationale_negative_button"
+      android:layout_marginHorizontal="16dp"
+      style="@style/TextButton"
+      android:text="@string/notification_permission_rationale_reject_button_text"/>
+
+</LinearLayout>

chrome/browser/notifications/android/java/src/org/chromium/chrome/browser/notifications/NotificationUmaTracker.java

@@ -194,6 +194,13 @@ public class NotificationUmaTracker {
             NotificationRationaleResult.NAVIGATE_BACK_OR_TOUCH_OUTSIDE,
             NotificationRationaleResult.NOT_ATTACHED_TO_WINDOW,
             NotificationRationaleResult.ACTIVITY_DESTROYED,
+            NotificationRationaleResult.BOTTOM_SHEET_BACK_PRESS,
+            NotificationRationaleResult.BOTTOM_SHEET_SWIPE,
+            NotificationRationaleResult.BOTTOM_SHEET_TAP_SCRIM,
+            NotificationRationaleResult.BOTTOM_SHEET_FAILED_TO_OPEN,
+            NotificationRationaleResult.BOTTOM_SHEET_DESTROYED,
+            NotificationRationaleResult.BOTTOM_SHEET_CLOSED_UNKNOWN,
+            NotificationRationaleResult.BOTTOM_SHEET_NEVER_OPENED,
             NotificationRationaleResult.NUM_ENTRIES})
     @Retention(RetentionPolicy.SOURCE)
     public @interface NotificationRationaleResult {
@@ -202,8 +209,15 @@ public class NotificationUmaTracker {
         int NAVIGATE_BACK_OR_TOUCH_OUTSIDE = 2;
         int ACTIVITY_DESTROYED = 3;
         int NOT_ATTACHED_TO_WINDOW = 4;
-
-        int NUM_ENTRIES = 5;
+        int BOTTOM_SHEET_BACK_PRESS = 5;
+        int BOTTOM_SHEET_SWIPE = 6;
+        int BOTTOM_SHEET_TAP_SCRIM = 7;
+        int BOTTOM_SHEET_FAILED_TO_OPEN = 8;
+        int BOTTOM_SHEET_DESTROYED = 9;
+        int BOTTOM_SHEET_CLOSED_UNKNOWN = 10;
+        int BOTTOM_SHEET_NEVER_OPENED = 11;
+
+        int NUM_ENTRIES = 12;
     }
 
     /**

chrome/browser/notifications/android/java/src/org/chromium/chrome/browser/notifications/permissions/NotificationPermissionController.java

@@ -51,6 +51,14 @@ public class NotificationPermissionController implements UnownedUserData {
     public static final String FIELD_TRIAL_PERMISSION_REQUEST_MAX_COUNT =
             "permission_request_max_count";
 
+    /**
+     * Returns whether the bottom sheet rationale UI should be used.
+     * @return true if the bottom sheet UI should be used, false if the dialog UI should be used.
+     */
+    public static boolean shouldUseBottomSheetRationaleUi() {
+        return ChromeFeatureList.isEnabled(ChromeFeatureList.NOTIFICATION_PERMISSION_BOTTOM_SHEET);
+    }
+
     /** Refers to what type of permission UI should be shown. */
     @IntDef({PermissionRequestMode.DO_NOT_REQUEST, PermissionRequestMode.REQUEST_ANDROID_PERMISSION,
             PermissionRequestMode.REQUEST_PERMISSION_WITH_RATIONALE})
@@ -69,13 +77,27 @@ public class NotificationPermissionController implements UnownedUserData {
         int REQUEST_PERMISSION_WITH_RATIONALE = 2;
     }
 
+    /**
+     * Refers to the result of trying to show the rationale UI.
+     */
+    @IntDef({RationaleUiResult.ACCEPTED, RationaleUiResult.REJECTED, RationaleUiResult.NOT_SHOWN})
+    public @interface RationaleUiResult {
+        /** Rationale UI was shown and user accepted. */
+        int ACCEPTED = 0;
+        /** Rationale UI was shown and user rejected or dismissed. */
+        int REJECTED = 1;
+        /** Rationale UI couldn't be shown. */
+        int NOT_SHOWN = 2;
+    }
+
     /** A delegate to show an in-app UI demonstrating rationale behind the permission request. */
-    interface RationaleDelegate {
+    public interface RationaleDelegate {
         /**
          * Called to show the in-app UI.
          * @param callback The callback to be invoked as part of the user action on the dialog UI.
+         *         Its argument is a value from {@code RationaleUiResult}.
          */
-        void showRationaleUi(Callback<Boolean> callback);
+        void showRationaleUi(Callback<Integer> callback);
     }
 
     private static final UnownedUserDataKey<NotificationPermissionController> KEY =
@@ -153,25 +175,37 @@ public boolean requestPermissionIfNeeded(boolean contextual) {
         int requestMode = shouldRequestPermission();
         if (requestMode == PermissionRequestMode.DO_NOT_REQUEST) return false;
 
-        SharedPreferencesManager.getInstance().incrementInt(
-                ChromePreferenceKeys.NOTIFICATION_PERMISSION_REQUEST_COUNT);
-        NotificationUmaTracker.getInstance().onNotificationPermissionRequested();
-
         if (requestMode == PermissionRequestMode.REQUEST_ANDROID_PERMISSION) {
             requestAndroidPermission();
+            recordOsPromptShown();
         } else if (requestMode == PermissionRequestMode.REQUEST_PERMISSION_WITH_RATIONALE) {
-            SharedPreferencesManager.getInstance().writeLong(
-                    ChromePreferenceKeys.NOTIFICATION_PERMISSION_RATIONALE_TIMESTAMP_KEY,
-                    System.currentTimeMillis());
-            mRationaleDelegate.showRationaleUi(accept -> {
-                if (accept) {
+            mRationaleDelegate.showRationaleUi(rationaleResult -> {
+                if (rationaleResult != RationaleUiResult.NOT_SHOWN) {
+                    recordRationaleUiShown();
+                }
+                if (rationaleResult == RationaleUiResult.ACCEPTED) {
                     requestAndroidPermission();
                 }
             });
         }
         return true;
     }
 
+    private void recordOsPromptShown() {
+        SharedPreferencesManager.getInstance().incrementInt(
+                ChromePreferenceKeys.NOTIFICATION_PERMISSION_REQUEST_COUNT);
+        NotificationUmaTracker.getInstance().onNotificationPermissionRequested();
+    }
+
+    private void recordRationaleUiShown() {
+        SharedPreferencesManager.getInstance().incrementInt(
+                ChromePreferenceKeys.NOTIFICATION_PERMISSION_REQUEST_COUNT);
+        NotificationUmaTracker.getInstance().onNotificationPermissionRequested();
+        SharedPreferencesManager.getInstance().writeLong(
+                ChromePreferenceKeys.NOTIFICATION_PERMISSION_RATIONALE_TIMESTAMP_KEY,
+                System.currentTimeMillis());
+    }
+
     @PermissionRequestMode
     int shouldRequestPermission() {
         // Notifications only require permission starting at Android T. And apps targeting < T can't