Merge changes from topics "addSettingsEntrypointToAddASupervisedUser", "simple fallback activity for supervised user creation"

* changes:
  Create a simple fallback activity for supervised user creation
  Add settings entrypoint to add a supervised user
diff --git a/AndroidManifest.xml b/AndroidManifest.xml
index 6e82b11..3fddf39 100644
--- a/AndroidManifest.xml
+++ b/AndroidManifest.xml
@@ -2974,6 +2974,12 @@
         </activity>
 
         <activity
+            android:name=".users.AddSupervisedUserActivity"
+            android:label="@*android:string/supervised_user_creation_label"
+            android:icon="@drawable/ic_settings_multiuser">
+        </activity>
+
+        <activity
             android:name="Settings$PaymentSettingsActivity"
             android:label="@string/nfc_payment_settings_title"
             android:exported="true"
diff --git a/res/layout/add_supervised_user.xml b/res/layout/add_supervised_user.xml
new file mode 100644
index 0000000..b95e0f7
--- /dev/null
+++ b/res/layout/add_supervised_user.xml
@@ -0,0 +1,26 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!--
+  ~ Copyright (C) 2021 The Android Open Source Project
+  ~
+  ~ Licensed under the Apache License, Version 2.0 (the "License");
+  ~ you may not use this file except in compliance with the License.
+  ~ You may obtain a copy of the License at
+  ~
+  ~      http://www.apache.org/licenses/LICENSE-2.0
+  ~
+  ~ Unless required by applicable law or agreed to in writing, software
+  ~ distributed under the License is distributed on an "AS IS" BASIS,
+  ~ WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+  ~ See the License for the specific language governing permissions and
+  ~ limitations under the License.
+  -->
+
+<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
+             android:layout_width="match_parent"
+             android:layout_height="match_parent">
+    <Button
+        android:id="@+id/createSupervisedUser"
+        android:layout_height="wrap_content"
+        android:layout_width="wrap_content"
+        android:text="@*android:string/supervised_user_creation_label" />
+</FrameLayout>
\ No newline at end of file
diff --git a/res/xml/user_settings.xml b/res/xml/user_settings.xml
index 5cafa1a..b3dc2ea 100644
--- a/res/xml/user_settings.xml
+++ b/res/xml/user_settings.xml
@@ -43,6 +43,12 @@
         android:icon="@drawable/ic_add_40dp"
         android:order="20"/>
 
+    <com.android.settingslib.RestrictedPreference
+        android:key="supervised_user_add"
+        android:title="@*android:string/supervised_user_creation_label"
+        android:icon="@*android:drawable/ic_add_supervised_user"
+        android:order="25"/>
+
     <com.android.settingslib.RestrictedSwitchPreference
         android:key="user_settings_add_users_when_locked"
         android:title="@string/user_add_on_lockscreen_menu"
diff --git a/src/com/android/settings/users/AddSupervisedUserActivity.java b/src/com/android/settings/users/AddSupervisedUserActivity.java
new file mode 100644
index 0000000..f3c5867
--- /dev/null
+++ b/src/com/android/settings/users/AddSupervisedUserActivity.java
@@ -0,0 +1,92 @@
+/*
+ * Copyright (C) 2021 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.android.settings.users;
+
+import android.app.Activity;
+import android.app.ActivityManager;
+import android.app.AlertDialog;
+import android.os.Bundle;
+import android.os.Handler;
+import android.os.Looper;
+import android.os.NewUserRequest;
+import android.os.NewUserResponse;
+import android.os.UserManager;
+
+import androidx.annotation.Nullable;
+
+import com.android.settings.R;
+
+import java.util.Objects;
+import java.util.concurrent.Executors;
+import java.util.function.Consumer;
+
+/**
+ * Fallback activity for supervised user creation.
+ * Built to test {@link UserManager#createUser(NewUserRequest)} API.
+ */
+// TODO(b/209659998): [to-be-removed] fallback activity for supervised user creation.
+public class AddSupervisedUserActivity extends Activity {
+
+    private UserManager mUserManager;
+    private ActivityManager mActivityManager;
+
+    @Override
+    protected void onCreate(@Nullable Bundle savedInstanceState) {
+        super.onCreate(savedInstanceState);
+        mUserManager = getSystemService(UserManager.class);
+        mActivityManager = getSystemService(ActivityManager.class);
+        setContentView(R.layout.add_supervised_user);
+        findViewById(R.id.createSupervisedUser).setOnClickListener(v -> createUser());
+    }
+
+    private void createUserAsync(final NewUserRequest request,
+            final Consumer<NewUserResponse> onResponse) {
+        Objects.requireNonNull(onResponse);
+
+        final Handler mMainThread = new Handler(Looper.getMainLooper());
+        Executors.newSingleThreadExecutor().execute(() -> {
+            final NewUserResponse response = mUserManager.createUser(request);
+            mMainThread.post(() -> onResponse.accept(response));
+        });
+    }
+
+    private void createUser() {
+        final NewUserRequest request = new NewUserRequest.Builder().build();
+
+        final AlertDialog pleaseWaitDialog = new AlertDialog.Builder(this)
+                .setMessage(getString(R.string.creating_new_user_dialog_message))
+                .setCancelable(false)
+                .create();
+
+        pleaseWaitDialog.show();
+        createUserAsync(request, response -> {
+            pleaseWaitDialog.dismiss();
+
+            if (response.isSuccessful()) {
+                mActivityManager.switchUser(response.getUser());
+                finish();
+            } else {
+                new AlertDialog.Builder(this)
+                        .setTitle(getString(R.string.add_user_failed))
+                        .setMessage(UserManager.UserOperationResult.class.getName()
+                                + " = " + response.getOperationResult())
+                        .setNeutralButton(getString(R.string.okay), null)
+                        .show();
+            }
+        });
+    }
+}
diff --git a/src/com/android/settings/users/UserSettings.java b/src/com/android/settings/users/UserSettings.java
index 096b6ee..c3f0439 100644
--- a/src/com/android/settings/users/UserSettings.java
+++ b/src/com/android/settings/users/UserSettings.java
@@ -115,6 +115,7 @@
     private static final String KEY_USER_GUEST = "user_guest";
     private static final String KEY_ADD_GUEST = "guest_add";
     private static final String KEY_ADD_USER = "user_add";
+    private static final String KEY_ADD_SUPERVISED_USER = "supervised_user_add";
     private static final String KEY_ADD_USER_WHEN_LOCKED = "user_settings_add_users_when_locked";
     private static final String KEY_MULTIUSER_TOP_INTRO = "multiuser_top_intro";
 
@@ -165,10 +166,13 @@
     @VisibleForTesting
     RestrictedPreference mAddUser;
     @VisibleForTesting
+    RestrictedPreference mAddSupervisedUser;
+    @VisibleForTesting
     SparseArray<Bitmap> mUserIcons = new SparseArray<>();
     private int mRemovingUserId = -1;
     private boolean mAddingUser;
     private boolean mGuestUserAutoCreated;
+    private String mConfigSupervisedUserCreationPackage;
     private String mAddingUserName;
     private UserCapabilities mUserCaps;
     private boolean mShouldUpdateUserList = true;
@@ -300,6 +304,10 @@
         }
         mAddUser.setOnPreferenceClickListener(this);
 
+        setConfigSupervisedUserCreationPackage();
+        mAddSupervisedUser = findPreference(KEY_ADD_SUPERVISED_USER);
+        mAddSupervisedUser.setOnPreferenceClickListener(this);
+
         activity.registerReceiverAsUser(
                 mUserChangeReceiver, UserHandle.ALL, USER_REMOVED_INTENT_FILTER, null, mHandler);
 
@@ -491,6 +499,21 @@
         }
     }
 
+    private void onAddSupervisedUserClicked() {
+        final Intent intent = new Intent()
+                .setAction(UserManager.ACTION_CREATE_SUPERVISED_USER)
+                .setPackage(mConfigSupervisedUserCreationPackage);
+
+        // TODO(b/209659998): [to-be-removed] fallback activity for supervised user creation.
+        if (getActivity().getPackageManager().resolveActivity(intent, 0) == null) {
+            intent
+                .setClass(getContext(), AddSupervisedUserActivity.class)
+                .setPackage(null);
+        }
+
+        startActivity(intent);
+    }
+
     private void onRemoveUserClicked(int userId) {
         synchronized (mUserLock) {
             if (mRemovingUserId == -1 && !mAddingUser) {
@@ -1058,6 +1081,7 @@
 
         updateAddGuest(context, users.stream().anyMatch(UserInfo::isGuest));
         updateAddUser(context);
+        updateAddSupervisedUser(context);
 
         if (!mUserCaps.mUserSwitcherEnabled) {
             return;
@@ -1070,6 +1094,12 @@
 
     }
 
+    @VisibleForTesting
+    void setConfigSupervisedUserCreationPackage() {
+        mConfigSupervisedUserCreationPackage = getPrefContext().getString(
+                com.android.internal.R.string.config_supervisedUserCreationPackage);
+    }
+
     private boolean isCurrentUserGuest() {
         return mUserCaps.mIsGuest;
     }
@@ -1100,28 +1130,41 @@
     }
 
     private void updateAddUser(Context context) {
+        updateAddUserCommon(context, mAddUser, mUserCaps.mCanAddRestrictedProfile);
+    }
+
+    private void updateAddSupervisedUser(Context context) {
+        if (!TextUtils.isEmpty(mConfigSupervisedUserCreationPackage)) {
+            updateAddUserCommon(context, mAddSupervisedUser, false);
+        } else {
+            mAddSupervisedUser.setVisible(false);
+        }
+    }
+
+    private void updateAddUserCommon(Context context, RestrictedPreference addUser,
+            boolean canAddRestrictedProfile) {
         if ((mUserCaps.mCanAddUser || mUserCaps.mDisallowAddUserSetByAdmin)
                 && WizardManagerHelper.isDeviceProvisioned(context)
                 && mUserCaps.mUserSwitcherEnabled) {
-            mAddUser.setVisible(true);
-            mAddUser.setSelectable(true);
+            addUser.setVisible(true);
+            addUser.setSelectable(true);
             final boolean canAddMoreUsers =
                     mUserManager.canAddMoreUsers(UserManager.USER_TYPE_FULL_SECONDARY)
-                            || (mUserCaps.mCanAddRestrictedProfile
+                            || (canAddRestrictedProfile
                             && mUserManager.canAddMoreUsers(UserManager.USER_TYPE_FULL_RESTRICTED));
-            mAddUser.setEnabled(canAddMoreUsers && !mAddingUser && canSwitchUserNow());
+            addUser.setEnabled(canAddMoreUsers && !mAddingUser && canSwitchUserNow());
             if (!canAddMoreUsers) {
-                mAddUser.setSummary(
+                addUser.setSummary(
                         getString(R.string.user_add_max_count, getRealUsersCount()));
             } else {
-                mAddUser.setSummary(null);
+                addUser.setSummary(null);
             }
-            if (mAddUser.isEnabled()) {
-                mAddUser.setDisabledByAdmin(
+            if (addUser.isEnabled()) {
+                addUser.setDisabledByAdmin(
                         mUserCaps.mDisallowAddUser ? mUserCaps.mEnforcedAdmin : null);
             }
         } else {
-            mAddUser.setVisible(false);
+            addUser.setVisible(false);
         }
     }
 
@@ -1206,6 +1249,9 @@
                 onAddUserClicked(USER_TYPE_USER);
             }
             return true;
+        } else if (pref == mAddSupervisedUser) {
+            onAddSupervisedUserClicked();
+            return true;
         } else if (pref == mAddGuest) {
             mAddGuest.setEnabled(false); // prevent multiple tap issue
             mMetricsFeatureProvider.action(getActivity(), SettingsEnums.ACTION_USER_GUEST_ADD);
diff --git a/tests/robotests/src/com/android/settings/users/UserSettingsTest.java b/tests/robotests/src/com/android/settings/users/UserSettingsTest.java
index 9d35797..d8f3959 100644
--- a/tests/robotests/src/com/android/settings/users/UserSettingsTest.java
+++ b/tests/robotests/src/com/android/settings/users/UserSettingsTest.java
@@ -59,6 +59,7 @@
 
 import com.android.settings.SettingsActivity;
 import com.android.settings.SubSettings;
+import com.android.settings.testutils.shadow.SettingsShadowResources;
 import com.android.settings.testutils.shadow.ShadowDevicePolicyManager;
 import com.android.settings.testutils.shadow.ShadowUserManager;
 import com.android.settingslib.RestrictedLockUtils;
@@ -85,7 +86,11 @@
 import java.util.List;
 
 @RunWith(RobolectricTestRunner.class)
-@Config(shadows = {ShadowUserManager.class, ShadowDevicePolicyManager.class})
+@Config(shadows = {
+        ShadowUserManager.class,
+        ShadowDevicePolicyManager.class,
+        SettingsShadowResources.class,
+})
 public class UserSettingsTest {
 
     private static final String KEY_USER_GUEST = "user_guest";
@@ -111,6 +116,8 @@
     @Mock
     private RestrictedPreference mAddUserPreference;
     @Mock
+    private RestrictedPreference mAddSupervisedUserPreference;
+    @Mock
     private RestrictedPreference mAddGuestPreference;
     @Mock
     private UserManager mUserManager;
@@ -161,6 +168,7 @@
 
         mFragment.mMePreference = mMePreference;
         mFragment.mAddUser = mAddUserPreference;
+        mFragment.mAddSupervisedUser = mAddSupervisedUserPreference;
         mFragment.mAddGuest = mAddGuestPreference;
         mFragment.mUserListCategory = mock(PreferenceCategory.class);
     }
@@ -169,6 +177,7 @@
     public void tearDown() {
         Settings.Global.putInt(mContext.getContentResolver(),
                 Settings.Global.DEVICE_PROVISIONED, mProvisionedBackupValue);
+        SettingsShadowResources.reset();
     }
 
     @Test
@@ -694,6 +703,36 @@
         verify(mUserManager).getUsers();
     }
 
+    private void setConfigSupervisedUserCreationPackage(String value) {
+        SettingsShadowResources.overrideResource(
+                com.android.internal.R.string.config_supervisedUserCreationPackage,
+                value
+        );
+        mFragment.setConfigSupervisedUserCreationPackage();
+        mUserCapabilities.mCanAddUser = true;
+        mFragment.updateUserList();
+    }
+
+    @Test
+    public void addSupervisedUserOption_resourceIsDefined_shouldBeDisplayed() {
+        try {
+            setConfigSupervisedUserCreationPackage("test");
+            verify(mAddSupervisedUserPreference).setVisible(true);
+        } finally {
+            SettingsShadowResources.reset();
+        }
+    }
+
+    @Test
+    public void addSupervisedUserOption_resourceIsNotDefined_shouldBeHidden() {
+        try {
+            setConfigSupervisedUserCreationPackage("");
+            verify(mAddSupervisedUserPreference).setVisible(false);
+        } finally {
+            SettingsShadowResources.reset();
+        }
+    }
+
     private void givenUsers(UserInfo... userInfo) {
         List<UserInfo> users = Arrays.asList(userInfo);
         doReturn(users).when(mUserManager).getUsers();