[Signin][Android] Replace boolean with enum states in web sign-in flow

This CL replaces the boolean flag IS_ACCOUNT_LIST_EXPANDED with enum
state class to represent different states of the account picker bottom
sheet. This refactoring will facilitate our future tasks of adding new
screens like |sign-in in progress| to the bottom sheet.

Bug: 1106442
Change-Id: I072693a393e14987c66888549956fdc49c386d36
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2311577Reviewed-by: Boris Sazonov <bsazonov@chromium.org>
Reviewed-by: Tanmoy Mollik <triploblastic@chromium.org>
Commit-Queue: Alice Wang <aliceywang@chromium.org>
Cr-Commit-Position: refs/heads/master@{#795370}

chrome/android/java/src/org/chromium/chrome/browser/signin/account_picker/AccountPickerBottomSheetMediator.java

@@ -12,6 +12,7 @@ import androidx.annotation.Nullable;
 
 import org.chromium.chrome.R;
 import org.chromium.chrome.browser.signin.ProfileDataCache;
+import org.chromium.chrome.browser.signin.account_picker.AccountPickerBottomSheetProperties.AccountPickerBottomSheetState;
 import org.chromium.components.signin.AccountManagerFacade;
 import org.chromium.components.signin.AccountManagerFacadeProvider;
 import org.chromium.components.signin.AccountUtils;
@@ -57,9 +58,10 @@ class AccountPickerBottomSheetMediator implements AccountPickerCoordinator.Liste
      */
     @Override
     public void onAccountSelected(String accountName, boolean isDefaultAccount) {
-        // Click on one account in the account list when the account list is expanded
+        // Clicking on one account in the account list when the account list is expanded
         // will collapse it to the selected account
-        mModel.set(AccountPickerBottomSheetProperties.IS_ACCOUNT_LIST_EXPANDED, false);
+        mModel.set(AccountPickerBottomSheetProperties.ACCOUNT_PICKER_BOTTOM_SHEET_STATE,
+                AccountPickerBottomSheetState.COLLAPSED_ACCOUNT_LIST);
         setSelectedAccountName(accountName);
     }
 
@@ -97,28 +99,31 @@ class AccountPickerBottomSheetMediator implements AccountPickerCoordinator.Liste
     private void onAccountListUpdated() {
         List<Account> accounts = mAccountManagerFacade.tryGetGoogleAccounts();
         if (accounts.isEmpty()) {
-            // If all accounts disappeared when the account list is collapsed, we will
-            // go to the zero account screen. If the account list is expanded, we will
-            // first set the account list state to collapsed then move to the zero
-            // account collapsed screen.
-            mModel.set(AccountPickerBottomSheetProperties.IS_ACCOUNT_LIST_EXPANDED, false);
+            // If all accounts disappeared, no matter if the account list is collapsed or expanded,
+            // we will go to the zero account screen.
+            mModel.set(AccountPickerBottomSheetProperties.ACCOUNT_PICKER_BOTTOM_SHEET_STATE,
+                    AccountPickerBottomSheetState.NO_ACCOUNTS);
             mSelectedAccountName = null;
             mModel.set(AccountPickerBottomSheetProperties.SELECTED_ACCOUNT_DATA, null);
-        } else if (!mModel.get(AccountPickerBottomSheetProperties.IS_ACCOUNT_LIST_EXPANDED)
-                && !isSelectedAccountInAccountList(accounts)) {
-            // The selected account is _only_ updated when the account list is collapsed and
-            // the current selected account name is not in the new account list
-            // (or there is no selected account).
-            setSelectedAccountName(accounts.get(0).name);
+            return;
         }
-    }
 
-    /**
-     * Returns true if there is selected account and it is in the account list.
-     */
-    private boolean isSelectedAccountInAccountList(List<Account> accounts) {
-        return mSelectedAccountName != null
-                && AccountUtils.findAccountByName(accounts, mSelectedAccountName) != null;
+        @AccountPickerBottomSheetState
+        int state =
+                mModel.get(AccountPickerBottomSheetProperties.ACCOUNT_PICKER_BOTTOM_SHEET_STATE);
+        if (state == AccountPickerBottomSheetState.NO_ACCOUNTS) {
+            // When a non-empty account list appears while it is currently zero-account screen,
+            // we should change the screen to collapsed account list and set the selected account
+            // to the first account of the account list
+            mModel.set(AccountPickerBottomSheetProperties.ACCOUNT_PICKER_BOTTOM_SHEET_STATE,
+                    AccountPickerBottomSheetState.COLLAPSED_ACCOUNT_LIST);
+            setSelectedAccountName(accounts.get(0).name);
+        } else if (state == AccountPickerBottomSheetState.COLLAPSED_ACCOUNT_LIST
+                && AccountUtils.findAccountByName(accounts, mSelectedAccountName) == null) {
+            // When it is already collapsed account list, we update the selected account only
+            // when the current selected account name is no longer in the new account list
+            setSelectedAccountName(accounts.get(0).name);
+        }
     }
 
     private void setSelectedAccountName(String accountName) {
@@ -144,7 +149,8 @@ class AccountPickerBottomSheetMediator implements AccountPickerCoordinator.Liste
     private void onSelectedAccountClicked() {
         // Clicking on the selected account when the account list is collapsed will expand the
         // account list and make the account list visible
-        mModel.set(AccountPickerBottomSheetProperties.IS_ACCOUNT_LIST_EXPANDED, true);
+        mModel.set(AccountPickerBottomSheetProperties.ACCOUNT_PICKER_BOTTOM_SHEET_STATE,
+                AccountPickerBottomSheetState.EXPANDED_ACCOUNT_LIST);
     }
 
     /**

chrome/android/java/src/org/chromium/chrome/browser/signin/account_picker/AccountPickerBottomSheetProperties.java

@@ -4,17 +4,71 @@
 
 package org.chromium.chrome.browser.signin.account_picker;
 
+import androidx.annotation.IntDef;
+
 import org.chromium.chrome.browser.signin.DisplayableProfileData;
 import org.chromium.ui.modelutil.PropertyKey;
 import org.chromium.ui.modelutil.PropertyModel;
 import org.chromium.ui.modelutil.PropertyModel.ReadableObjectPropertyKey;
-import org.chromium.ui.modelutil.PropertyModel.WritableBooleanPropertyKey;
+import org.chromium.ui.modelutil.PropertyModel.WritableIntPropertyKey;
 import org.chromium.ui.modelutil.PropertyModel.WritableObjectPropertyKey;
 
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+
 /**
  * Properties of account picker bottom sheet.
  */
 class AccountPickerBottomSheetProperties {
+    /**
+     * States of account picker.
+     * Different account picker state correspond to different account picker bottom sheet
+     * configuration.
+     */
+    @IntDef({AccountPickerBottomSheetState.NO_ACCOUNTS,
+            AccountPickerBottomSheetState.COLLAPSED_ACCOUNT_LIST,
+            AccountPickerBottomSheetState.EXPANDED_ACCOUNT_LIST,
+            AccountPickerBottomSheetState.SIGNIN_IN_PROGRESS})
+    @Retention(RetentionPolicy.SOURCE)
+    @interface AccountPickerBottomSheetState {
+        /**
+         * When there is no account on device, the user sees only one blue button
+         * |Add account to device|.
+         *
+         * The bottom sheet starts with this state when there is zero account on device.
+         */
+        int NO_ACCOUNTS = 0;
+
+        /**
+         * When the account list is collapsed with exactly one account shown as the selected
+         * account and a blue |Continue as| button to sign in with the selected account.
+         *
+         * The bottom sheet starts with this state when there is at least one account on device.
+         *
+         * This state can also be reached from EXPANDED_ACCOUNT_LIST by clicking on one of
+         * the accounts in the expanded account list.
+         */
+        int COLLAPSED_ACCOUNT_LIST = 1;
+
+        /**
+         * When the account list is expanded, the user sees the account list of all the accounts
+         * on device and some additional rows like |Add account to device| and |Go incognito mode|.
+         *
+         * This state is reached from COLLAPSED_ACCOUNT_LIST by clicking the selected account of
+         * the collapsed account list.
+         */
+        int EXPANDED_ACCOUNT_LIST = 2;
+
+        /**
+         * When the user is in the sign-in process, no account or button will be visible, the user
+         * sees mainly a spinner in the bottom sheet.
+         *
+         * This state can only be reached from COLLAPSED_ACCOUNT_LIST, when the button
+         * |Continue as| is clicked. This state does not lead to any other state.
+         */
+        int SIGNIN_IN_PROGRESS = 3;
+    }
+
     // PropertyKeys for the selected account view when the account list is collapsed.
     // The selected account view is replaced by account list view when the
     // account list is expanded.
@@ -28,20 +82,26 @@ class AccountPickerBottomSheetProperties {
     static final ReadableObjectPropertyKey<Runnable> ON_CONTINUE_AS_CLICKED =
             new ReadableObjectPropertyKey<>("on_continue_as_clicked");
 
-    // PropertyKey indicates if the account list is expanded
-    static final WritableBooleanPropertyKey IS_ACCOUNT_LIST_EXPANDED =
-            new WritableBooleanPropertyKey("is_account_list_expanded");
+    // PropertyKey indicates the state of the account picker bottom sheet
+    static final WritableIntPropertyKey ACCOUNT_PICKER_BOTTOM_SHEET_STATE =
+            new WritableIntPropertyKey("account_picker_bottom_sheet_state");
 
     static final PropertyKey[] ALL_KEYS = new PropertyKey[] {ON_SELECTED_ACCOUNT_CLICKED,
-            SELECTED_ACCOUNT_DATA, ON_CONTINUE_AS_CLICKED, IS_ACCOUNT_LIST_EXPANDED};
+            SELECTED_ACCOUNT_DATA, ON_CONTINUE_AS_CLICKED, ACCOUNT_PICKER_BOTTOM_SHEET_STATE};
 
+    /**
+     * Creates a default model for the AccountPickerBottomSheet.
+     *
+     * In the default model, as the selected account data is null, the bottom sheet is in the
+     * state {@link AccountPickerBottomSheetState#NO_ACCOUNTS}.
+     */
     static PropertyModel createModel(
             Runnable onSelectedAccountClicked, Runnable onContinueAsClicked) {
         return new PropertyModel.Builder(ALL_KEYS)
                 .with(ON_SELECTED_ACCOUNT_CLICKED, onSelectedAccountClicked)
                 .with(SELECTED_ACCOUNT_DATA, null)
                 .with(ON_CONTINUE_AS_CLICKED, onContinueAsClicked)
-                .with(IS_ACCOUNT_LIST_EXPANDED, false)
+                .with(ACCOUNT_PICKER_BOTTOM_SHEET_STATE, AccountPickerBottomSheetState.NO_ACCOUNTS)
                 .build();
     }
 

chrome/android/java/src/org/chromium/chrome/browser/signin/account_picker/AccountPickerBottomSheetView.java

@@ -74,35 +74,39 @@ class AccountPickerBottomSheetView implements BottomSheetContent {
     }
 
     /**
-     * Collapses the account list.
-     * If there is a non null selected account, the account list will collapse to that account,
-     * otherwise, the account list will just collapse the remaining.
-     *
-     * @param isSelectedAccountNonNull Flag indicates if the selected profile data exists
-     *                                 in model.
+     * Collapses the account list to the selected account.
      */
-    void collapseAccountList(boolean isSelectedAccountNonNull) {
+    void collapseAccountList() {
         mAccountListView.setVisibility(View.GONE);
-        mSelectedAccountView.setVisibility(isSelectedAccountNonNull ? View.VISIBLE : View.GONE);
+        mSelectedAccountView.setVisibility(View.VISIBLE);
         mContinueAsButton.setVisibility(View.VISIBLE);
     }
 
     /**
-     * Updates the view of the collapsed account list.
+     * Collapses the account list to the no account view.
      */
-    void updateCollapsedAccountList(DisplayableProfileData accountProfileData) {
-        if (accountProfileData == null) {
-            mContinueAsButton.setText(R.string.signin_add_account_to_device);
-        } else {
-            ExistingAccountRowViewBinder.bindAccountView(accountProfileData, mSelectedAccountView);
-
-            ImageView rowEndImage = mSelectedAccountView.findViewById(R.id.account_selection_mark);
-            rowEndImage.setImageResource(R.drawable.ic_expand_more_in_circle_24dp);
-
-            String continueAsButtonText = mContext.getString(R.string.signin_promo_continue_as,
-                    accountProfileData.getGivenNameOrFullNameOrEmail());
-            mContinueAsButton.setText(continueAsButtonText);
-        }
+    void collapseToNoAccountView() {
+        mAccountListView.setVisibility(View.GONE);
+        mSelectedAccountView.setVisibility(View.GONE);
+        mContinueAsButton.setVisibility(View.VISIBLE);
+        mContinueAsButton.setText(R.string.signin_add_account_to_device);
+    }
+
+    /**
+     * Updates the views related to the selected account.
+     *
+     * This method only updates the UI elements like text related to the selected account, it
+     * does not change the visibility.
+     */
+    void updateSelectedAccount(DisplayableProfileData accountProfileData) {
+        ExistingAccountRowViewBinder.bindAccountView(accountProfileData, mSelectedAccountView);
+
+        ImageView rowEndImage = mSelectedAccountView.findViewById(R.id.account_selection_mark);
+        rowEndImage.setImageResource(R.drawable.ic_expand_more_in_circle_24dp);
+
+        String continueAsButtonText = mContext.getString(R.string.signin_promo_continue_as,
+                accountProfileData.getGivenNameOrFullNameOrEmail());
+        mContinueAsButton.setText(continueAsButtonText);
     }
 
     @Override

chrome/android/java/src/org/chromium/chrome/browser/signin/account_picker/AccountPickerBottomSheetViewBinder.java

@@ -5,6 +5,7 @@
 package org.chromium.chrome.browser.signin.account_picker;
 
 import org.chromium.chrome.browser.signin.DisplayableProfileData;
+import org.chromium.chrome.browser.signin.account_picker.AccountPickerBottomSheetProperties.AccountPickerBottomSheetState;
 import org.chromium.ui.modelutil.PropertyKey;
 import org.chromium.ui.modelutil.PropertyModel;
 
@@ -18,22 +19,17 @@ class AccountPickerBottomSheetViewBinder {
             view.getSelectedAccountView().setOnClickListener(v -> {
                 model.get(AccountPickerBottomSheetProperties.ON_SELECTED_ACCOUNT_CLICKED).run();
             });
-        } else if (propertyKey == AccountPickerBottomSheetProperties.IS_ACCOUNT_LIST_EXPANDED) {
-            if (model.get(AccountPickerBottomSheetProperties.IS_ACCOUNT_LIST_EXPANDED)) {
-                view.expandAccountList();
-            } else {
-                boolean isSelectedAccountNonNull =
-                        model.get(AccountPickerBottomSheetProperties.SELECTED_ACCOUNT_DATA) != null;
-                view.collapseAccountList(isSelectedAccountNonNull);
-            }
+        } else if (propertyKey
+                == AccountPickerBottomSheetProperties.ACCOUNT_PICKER_BOTTOM_SHEET_STATE) {
+            @AccountPickerBottomSheetState
+            int state =
+                    model.get(AccountPickerBottomSheetProperties.ACCOUNT_PICKER_BOTTOM_SHEET_STATE);
+            switchToState(view, state);
         } else if (propertyKey == AccountPickerBottomSheetProperties.SELECTED_ACCOUNT_DATA) {
-            if (!model.get(AccountPickerBottomSheetProperties.IS_ACCOUNT_LIST_EXPANDED)) {
-                // Selected account data (which can be null) is only updated
-                // when the account list is collapsed.
-                DisplayableProfileData profileData =
-                        model.get(AccountPickerBottomSheetProperties.SELECTED_ACCOUNT_DATA);
-                view.collapseAccountList(profileData != null);
-                view.updateCollapsedAccountList(profileData);
+            DisplayableProfileData profileData =
+                    model.get(AccountPickerBottomSheetProperties.SELECTED_ACCOUNT_DATA);
+            if (profileData != null) {
+                view.updateSelectedAccount(profileData);
             }
         } else if (propertyKey == AccountPickerBottomSheetProperties.ON_CONTINUE_AS_CLICKED) {
             view.getContinueAsButton().setOnClickListener(v -> {
@@ -42,5 +38,30 @@ class AccountPickerBottomSheetViewBinder {
         }
     }
 
+    /**
+     * Sets up the configuration of account picker bottom sheet according to the given state.
+     */
+    private static void switchToState(AccountPickerBottomSheetView view,
+            @AccountPickerBottomSheetState int accountPickerBottomSheetState) {
+        switch (accountPickerBottomSheetState) {
+            case AccountPickerBottomSheetState.NO_ACCOUNTS:
+                view.collapseToNoAccountView();
+                break;
+            case AccountPickerBottomSheetState.COLLAPSED_ACCOUNT_LIST:
+                view.collapseAccountList();
+                break;
+            case AccountPickerBottomSheetState.EXPANDED_ACCOUNT_LIST:
+                view.expandAccountList();
+                break;
+            case AccountPickerBottomSheetState.SIGNIN_IN_PROGRESS:
+                // TODO(https://crbug.com/1102784): Implement UI update when sign-in in progress
+                break;
+            default:
+                throw new IllegalArgumentException(
+                        "Cannot bind AccountPickerBottomSheetView for the state:"
+                        + accountPickerBottomSheetState);
+        }
+    }
+
     private AccountPickerBottomSheetViewBinder() {}
 }