Safety check on Android: added the last run timestamp to the UI

UI demo: https://screenshot.googleplex.com/PdYajrS8FfE.gif

Bug: 1070620, 1107807
Change-Id: I2fac517d4aefd5999449988cfe7d289f76e67563
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2303714Reviewed-by: Theresa  <twellington@chromium.org>
Reviewed-by: Natalie Chouinard <chouinard@chromium.org>
Reviewed-by: Martin Šrámek <msramek@chromium.org>
Commit-Queue: Andrey Zaytsev <andzaytsev@google.com>
Auto-Submit: Andrey Zaytsev <andzaytsev@google.com>
Cr-Commit-Position: refs/heads/master@{#791461}

chrome/browser/preferences/android/java/src/org/chromium/chrome/browser/preferences/ChromePreferenceKeys.java

@@ -593,6 +593,10 @@ public final class ChromePreferenceKeys {
             "org.chromium.chrome.browser.settings.privacy."
             + "PREF_OTHER_FORMS_OF_HISTORY_DIALOG_SHOWN";
 
+    /** Stores the timestamp of the last performed Safety check. */
+    public static final String SETTINGS_SAFETY_CHECK_LAST_RUN_TIMESTAMP =
+            "Chrome.SafetyCheck.LastRunTimestamp";
+
     /** Stores the number of times the user has performed Safety check. */
     public static final String SETTINGS_SAFETY_CHECK_RUN_COUNTER = "Chrome.SafetyCheck.RunCounter";
 
@@ -800,6 +804,7 @@ public final class ChromePreferenceKeys {
                 HOMEPAGE_USE_CHROME_NTP,
                 PROMO_IS_DISMISSED.pattern(),
                 PROMO_TIMES_SEEN.pattern(),
+                SETTINGS_SAFETY_CHECK_LAST_RUN_TIMESTAMP,
                 SETTINGS_SAFETY_CHECK_RUN_COUNTER,
                 TWA_DISCLOSURE_SEEN_PACKAGES
         );

chrome/browser/safety_check/android/BUILD.gn

@@ -100,7 +100,7 @@ android_library("junit") {
 
 android_resources("java_resources") {
   sources = [
-    "java/res/layout/safety_check_button.xml",
+    "java/res/layout/safety_check_bottom_elements.xml",
     "java/res/layout/safety_check_status.xml",
     "java/res/values/dimens.xml",
     "java/res/xml/safety_check_preferences.xml",

chrome/browser/safety_check/android/java/res/layout/safety_check_bottom_elements.xml

+<?xml version="1.0" encoding="utf-8"?>
+<!-- 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. -->
+
+<LinearLayout
+    xmlns:android="http://schemas.android.com/apk/res/android"
+    android:layout_width="wrap_content"
+    android:layout_height="wrap_content"
+    android:orientation="vertical"
+    android:layout_gravity="end" >
+     <!-- Text view for displaying the timestamp of the last run. -->
+     <TextView
+          android:id="@+id/safety_check_timestamp"
+          android:layout_marginEnd="@dimen/safety_check_button_margin"
+          android:layout_width="wrap_content"
+          android:layout_height="wrap_content"
+          android:layout_gravity="end" />
+     <!-- Button for starting Safety check. -->
+     <org.chromium.ui.widget.ButtonCompat
+          android:id="@+id/safety_check_button"
+          style="@style/FilledButton.Flat"
+          android:layout_width="wrap_content"
+          android:layout_height="wrap_content"
+          android:layout_gravity="end"
+          android:layout_margin="@dimen/safety_check_button_margin"
+          android:focusable="true"
+          android:text="@string/safety_check_button" />
+</LinearLayout>

chrome/browser/safety_check/android/java/res/layout/safety_check_button.xml

-<?xml version="1.0" encoding="utf-8"?>
-<!-- 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. -->
-
-<!-- Button for starting Safety check. -->
-<org.chromium.ui.widget.ButtonCompat xmlns:android="http://schemas.android.com/apk/res/android"
-    android:id="@+id/safety_check_button"
-    style="@style/FilledButton.Flat"
-    android:layout_width="wrap_content"
-    android:layout_height="wrap_content"
-    android:layout_gravity="end"
-    android:layout_margin="@dimen/safety_check_button_margin"
-    android:focusable="true"
-    android:text="@string/safety_check_button" />

chrome/browser/safety_check/android/java/res/layout/safety_check_status.xml

@@ -5,7 +5,6 @@
 
 <FrameLayout
     xmlns:android="http://schemas.android.com/apk/res/android"
-    xmlns:tools="http://schemas.android.com/tools"
     android:layout_width="wrap_content"
     android:layout_height="match_parent">
      <!-- Spinning icon indicating a running check. -->

chrome/browser/safety_check/android/java/src/org/chromium/chrome/browser/safety_check/SafetyCheckMediator.java

@@ -80,6 +80,10 @@ class SafetyCheckMediator implements SafetyCheckCommonObserver {
         // Set the listener for clicking the Check button.
         mModel.set(SafetyCheckProperties.SAFETY_CHECK_BUTTON_CLICK_LISTENER,
                 (View.OnClickListener) (v) -> performSafetyCheck());
+        // Get the timestamp of the last run.
+        mModel.set(SafetyCheckProperties.LAST_RUN_TIMESTAMP,
+                mPreferenceManager.readLong(
+                        ChromePreferenceKeys.SETTINGS_SAFETY_CHECK_LAST_RUN_TIMESTAMP, 0));
     }
 
     /** Triggers all safety check child checks. */
@@ -89,6 +93,11 @@ class SafetyCheckMediator implements SafetyCheckCommonObserver {
         cancelCallbacks();
         // Record the start time for tracking 1 second checking delay in the UI.
         mCheckStartTime = SystemClock.elapsedRealtime();
+        // Record the absolute start time for showing when the last Safety check was performed.
+        long currentTime = System.currentTimeMillis();
+        mModel.set(SafetyCheckProperties.LAST_RUN_TIMESTAMP, currentTime);
+        mPreferenceManager.writeLong(
+                ChromePreferenceKeys.SETTINGS_SAFETY_CHECK_LAST_RUN_TIMESTAMP, currentTime);
         // Increment the stored number of Safety check starts.
         mPreferenceManager.incrementInt(ChromePreferenceKeys.SETTINGS_SAFETY_CHECK_RUN_COUNTER);
         // Set the checking state for all elements.

chrome/browser/safety_check/android/java/src/org/chromium/chrome/browser/safety_check/SafetyCheckProperties.java

@@ -10,6 +10,7 @@ import org.chromium.chrome.browser.password_check.BulkLeakCheckServiceState;
 import org.chromium.ui.modelutil.PropertyKey;
 import org.chromium.ui.modelutil.PropertyModel;
 import org.chromium.ui.modelutil.PropertyModel.WritableIntPropertyKey;
+import org.chromium.ui.modelutil.PropertyModel.WritableLongPropertyKey;
 import org.chromium.ui.modelutil.PropertyModel.WritableObjectPropertyKey;
 
 import java.lang.annotation.Retention;
@@ -25,6 +26,8 @@ class SafetyCheckProperties {
     /** Listener for Safety check button click events. */
     static final WritableObjectPropertyKey SAFETY_CHECK_BUTTON_CLICK_LISTENER =
             new WritableObjectPropertyKey();
+    /** Timestamp of the last run, a Long object. */
+    static final WritableLongPropertyKey LAST_RUN_TIMESTAMP = new WritableLongPropertyKey();
 
     @IntDef({PasswordsState.UNCHECKED, PasswordsState.CHECKING, PasswordsState.SAFE,
             PasswordsState.COMPROMISED_EXIST, PasswordsState.OFFLINE, PasswordsState.NO_PASSWORDS,
@@ -112,13 +115,14 @@ class SafetyCheckProperties {
     }
 
     static final PropertyKey[] ALL_KEYS = new PropertyKey[] {PASSWORDS_STATE, SAFE_BROWSING_STATE,
-            UPDATES_STATE, SAFETY_CHECK_BUTTON_CLICK_LISTENER};
+            UPDATES_STATE, SAFETY_CHECK_BUTTON_CLICK_LISTENER, LAST_RUN_TIMESTAMP};
 
     static PropertyModel createSafetyCheckModel() {
         return new PropertyModel.Builder(ALL_KEYS)
                 .with(PASSWORDS_STATE, PasswordsState.UNCHECKED)
                 .with(SAFE_BROWSING_STATE, SafeBrowsingState.UNCHECKED)
                 .with(UPDATES_STATE, UpdatesState.UNCHECKED)
+                .with(LAST_RUN_TIMESTAMP, 0)
                 .build();
     }
 }

chrome/browser/safety_check/android/java/src/org/chromium/chrome/browser/safety_check/SafetyCheckSettingsFragment.java

@@ -13,6 +13,7 @@ import android.view.LayoutInflater;
 import android.view.View;
 import android.view.ViewGroup;
 import android.widget.LinearLayout;
+import android.widget.TextView;
 
 import androidx.preference.Preference;
 import androidx.preference.PreferenceFragmentCompat;
@@ -35,6 +36,8 @@ public class SafetyCheckSettingsFragment extends PreferenceFragmentCompat {
     /** The "Check" button at the bottom that needs to be added after the View is inflated. */
     private ButtonCompat mCheckButton;
 
+    private TextView mTimestampTextView;
+
     public static CharSequence getSafetyCheckSettingsElementTitle(Context context) {
         SharedPreferencesManager preferenceManager = SharedPreferencesManager.getInstance();
         if (preferenceManager.readInt(ChromePreferenceKeys.SETTINGS_SAFETY_CHECK_RUN_COUNTER)
@@ -77,18 +80,28 @@ public class SafetyCheckSettingsFragment extends PreferenceFragmentCompat {
         LinearLayout view =
                 (LinearLayout) super.onCreateView(inflater, container, savedInstanceState);
         // Add a button to the bottom of the preferences view.
-        mCheckButton = (ButtonCompat) inflater.inflate(R.layout.safety_check_button, view, false);
-        view.addView(mCheckButton);
+        LinearLayout bottomView =
+                (LinearLayout) inflater.inflate(R.layout.safety_check_bottom_elements, view, false);
+        mCheckButton = (ButtonCompat) bottomView.findViewById(R.id.safety_check_button);
+        mTimestampTextView = (TextView) bottomView.findViewById(R.id.safety_check_timestamp);
+        view.addView(bottomView);
         return view;
     }
 
     /**
      * @return A {@link ButtonCompat} object for the Check button.
      */
-    public ButtonCompat getCheckButton() {
+    ButtonCompat getCheckButton() {
         return mCheckButton;
     }
 
+    /**
+     * @return A {@link TextView} object for the last run timestamp.
+     */
+    TextView getTimestampTextView() {
+        return mTimestampTextView;
+    }
+
     /**
      * Update the status string of a given Safety check element, e.g. Passwords.
      * @param key An android:key String corresponding to Safety check element.

chrome/browser/safety_check/android/java/src/org/chromium/chrome/browser/safety_check/SafetyCheckViewBinder.java

@@ -4,8 +4,11 @@
 
 package org.chromium.chrome.browser.safety_check;
 
+import android.content.Context;
 import android.view.View;
 
+import androidx.annotation.VisibleForTesting;
+
 import org.chromium.chrome.browser.safety_check.SafetyCheckProperties.PasswordsState;
 import org.chromium.chrome.browser.safety_check.SafetyCheckProperties.SafeBrowsingState;
 import org.chromium.chrome.browser.safety_check.SafetyCheckProperties.UpdatesState;
@@ -16,6 +19,9 @@ class SafetyCheckViewBinder {
     private static final String PASSWORDS_KEY = "passwords";
     private static final String SAFE_BROWSING_KEY = "safe_browsing";
     private static final String UPDATES_KEY = "updates";
+    private static final long MIN_TO_MS = 60 * 1000;
+    private static final long H_TO_MS = 60 * MIN_TO_MS;
+    private static final long DAY_TO_MS = 24 * H_TO_MS;
 
     private static int getStringForPasswords(@PasswordsState int state) {
         switch (state) {
@@ -142,6 +148,42 @@ class SafetyCheckViewBinder {
         return 0;
     }
 
+    /**
+     * Generates a String representing how long ago the Safety check was performed last time.
+     * @param context A {@link Context} instance to extract the strings.
+     * @param lastRunTime A long representing the last run timestamp in milliseconds.
+     * @param currentTime A long representing current time in milliseconds.
+     * @return A string to display in the UI for the last run timestamp.
+     */
+    @VisibleForTesting
+    static String getLastRunTimestampText(Context context, long lastRunTime, long currentTime) {
+        if (lastRunTime == 0) {
+            return "";
+        }
+        long timeDiff = currentTime - lastRunTime;
+        if (timeDiff < MIN_TO_MS) {
+            return context.getString(R.string.safety_check_timestamp_after);
+        } else if (timeDiff < H_TO_MS) {
+            int minutes = (int) (timeDiff / MIN_TO_MS);
+            return context.getResources().getQuantityString(
+                    R.plurals.safety_check_timestamp_after_mins, minutes, minutes);
+        } else if (timeDiff < DAY_TO_MS) {
+            int hours = (int) (timeDiff / H_TO_MS);
+            return context.getResources().getQuantityString(
+                    R.plurals.safety_check_timestamp_after_hours, hours, hours);
+        } else if (timeDiff < 2 * DAY_TO_MS) {
+            return context.getString(R.string.safety_check_timestamp_after_yesterday);
+        } else {
+            int days = (int) (timeDiff / DAY_TO_MS);
+            return context.getResources().getQuantityString(
+                    R.plurals.safety_check_timestamp_after_days, days, days);
+        }
+    }
+
+    private static void clearTimestampText(SafetyCheckSettingsFragment fragment) {
+        fragment.getTimestampTextView().setText("");
+    }
+
     static void bind(
             PropertyModel model, SafetyCheckSettingsFragment fragment, PropertyKey propertyKey) {
         if (SafetyCheckProperties.PASSWORDS_STATE == propertyKey) {
@@ -149,10 +191,12 @@ class SafetyCheckViewBinder {
             int state = model.get(SafetyCheckProperties.PASSWORDS_STATE);
             fragment.updateElementStatus(PASSWORDS_KEY, getStringForPasswords(state));
             SafetyCheckElementPreference preference = fragment.findPreference(PASSWORDS_KEY);
+            preference.setEnabled(true);
             if (state == PasswordsState.UNCHECKED) {
                 preference.clearStatusIndicator();
                 preference.setEnabled(true);
             } else if (state == PasswordsState.CHECKING) {
+                clearTimestampText(fragment);
                 preference.showProgressBar();
                 preference.setEnabled(false);
             } else {
@@ -164,10 +208,12 @@ class SafetyCheckViewBinder {
             int state = model.get(SafetyCheckProperties.SAFE_BROWSING_STATE);
             fragment.updateElementStatus(SAFE_BROWSING_KEY, getStringForSafeBrowsing(state));
             SafetyCheckElementPreference preference = fragment.findPreference(SAFE_BROWSING_KEY);
+            preference.setEnabled(true);
             if (state == SafeBrowsingState.UNCHECKED) {
                 preference.clearStatusIndicator();
                 preference.setEnabled(true);
             } else if (state == SafeBrowsingState.CHECKING) {
+                clearTimestampText(fragment);
                 preference.showProgressBar();
                 preference.setEnabled(false);
             } else {
@@ -179,10 +225,12 @@ class SafetyCheckViewBinder {
             int state = model.get(SafetyCheckProperties.UPDATES_STATE);
             fragment.updateElementStatus(UPDATES_KEY, getStringForUpdates(state));
             SafetyCheckElementPreference preference = fragment.findPreference(UPDATES_KEY);
+            preference.setEnabled(true);
             if (state == UpdatesState.UNCHECKED) {
                 preference.clearStatusIndicator();
                 preference.setEnabled(true);
             } else if (state == UpdatesState.CHECKING) {
+                clearTimestampText(fragment);
                 preference.showProgressBar();
                 preference.setEnabled(false);
             } else {
@@ -192,6 +240,11 @@ class SafetyCheckViewBinder {
         } else if (SafetyCheckProperties.SAFETY_CHECK_BUTTON_CLICK_LISTENER == propertyKey) {
             fragment.getCheckButton().setOnClickListener((View.OnClickListener) model.get(
                     SafetyCheckProperties.SAFETY_CHECK_BUTTON_CLICK_LISTENER));
+        } else if (SafetyCheckProperties.LAST_RUN_TIMESTAMP == propertyKey) {
+            long lastRunTime = model.get(SafetyCheckProperties.LAST_RUN_TIMESTAMP);
+            long currentTime = System.currentTimeMillis();
+            fragment.getTimestampTextView().setText(
+                    getLastRunTimestampText(fragment.getContext(), lastRunTime, currentTime));
         } else {
             assert false : "Unhandled property detected in SafetyCheckViewBinder!";
         }

chrome/browser/safety_check/android/javatests/src/org/chromium/chrome/browser/safety_check/SafetyCheckSettingsFragmentTest.java

@@ -8,6 +8,7 @@ import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertFalse;
 import static org.junit.Assert.assertTrue;
 
+import android.content.Context;
 import android.support.test.InstrumentationRegistry;
 
 import androidx.preference.Preference;
@@ -36,6 +37,11 @@ public class SafetyCheckSettingsFragmentTest {
     private static final String PASSWORDS = "passwords";
     private static final String SAFE_BROWSING = "safe_browsing";
     private static final String UPDATES = "updates";
+    private static final long S_TO_MS = 1000;
+    private static final long MIN_TO_MS = 60 * S_TO_MS;
+    private static final long H_TO_MS = 60 * MIN_TO_MS;
+    private static final long DAY_TO_MS = 24 * H_TO_MS;
+
     @Rule
     public SettingsActivityTestRule<SafetyCheckSettingsFragment> mSettingsActivityTestRule =
             new SettingsActivityTestRule<>(SafetyCheckSettingsFragment.class);
@@ -77,10 +83,38 @@ public class SafetyCheckSettingsFragmentTest {
         assertFalse(title.contains("New"));
     }
 
+    @Test
+    @SmallTest
+    public void testLastRunTimestampStrings() {
+        long t0 = 12345;
+        Context context = InstrumentationRegistry.getTargetContext();
+        // Start time not set - returns an empty string.
+        assertEquals("", SafetyCheckViewBinder.getLastRunTimestampText(context, 0, 123));
+        assertEquals("Checked just now",
+                SafetyCheckViewBinder.getLastRunTimestampText(context, t0, t0 + 10 * S_TO_MS));
+        assertEquals("Checked 1 minute ago",
+                SafetyCheckViewBinder.getLastRunTimestampText(context, t0, t0 + MIN_TO_MS));
+        assertEquals("Checked 17 minutes ago",
+                SafetyCheckViewBinder.getLastRunTimestampText(context, t0, t0 + 17 * MIN_TO_MS));
+        assertEquals("Checked 1 hour ago",
+                SafetyCheckViewBinder.getLastRunTimestampText(context, t0, t0 + H_TO_MS));
+        assertEquals("Checked 13 hours ago",
+                SafetyCheckViewBinder.getLastRunTimestampText(context, t0, t0 + 13 * H_TO_MS));
+        assertEquals("Checked yesterday",
+                SafetyCheckViewBinder.getLastRunTimestampText(context, t0, t0 + DAY_TO_MS));
+        assertEquals("Checked yesterday",
+                SafetyCheckViewBinder.getLastRunTimestampText(context, t0, t0 + 2 * DAY_TO_MS - 1));
+        assertEquals("Checked 2 days ago",
+                SafetyCheckViewBinder.getLastRunTimestampText(context, t0, t0 + 2 * DAY_TO_MS));
+        assertEquals("Checked 315 days ago",
+                SafetyCheckViewBinder.getLastRunTimestampText(context, t0, t0 + 315 * DAY_TO_MS));
+    }
+
     private void createFragmentAndModel() {
         mSettingsActivityTestRule.startSettingsActivity();
         mFragment = (SafetyCheckSettingsFragment) mSettingsActivityTestRule.getFragment();
-        mModel = SafetyCheckCoordinator.createModelAndMcp(mFragment);
+        TestThreadUtils.runOnUiThreadBlocking(
+                () -> { mModel = SafetyCheckCoordinator.createModelAndMcp(mFragment); });
     }
 
     @Test

chrome/browser/ui/android/strings/android_chrome_strings.grd

@@ -925,6 +925,27 @@ Your Google account may have other forms of browsing history like searches and a
       <message name="IDS_SAFETY_CHECK_UPDATES_ERROR" desc="Text to display when the updates check failed for some reason.">
         Chrome can’t check for updates
       </message>
+      <message name="IDS_SAFETY_CHECK_TIMESTAMP_AFTER" desc="A message shown on the safety check page, explaining to the user that it ran a moment ago.">
+        Checked just now
+      </message>
+      <message name="IDS_SAFETY_CHECK_TIMESTAMP_AFTER_MINS" desc="A message shown on the safety check page, explaining to the user that it ran minutes ago.">
+        {NUM_MINS, plural,
+        =1 {Checked 1 minute ago}
+        other {Checked # minutes ago}}
+      </message>
+      <message name="IDS_SAFETY_CHECK_TIMESTAMP_AFTER_HOURS" desc="A message shown on the safety check page, explaining to the user that it ran hours ago.">
+        {NUM_HOURS, plural,
+        =1 {Checked 1 hour ago}
+        other {Checked # hours ago}}
+      </message>
+      <message name="IDS_SAFETY_CHECK_TIMESTAMP_AFTER_YESTERDAY" desc="A message shown on the safety check page, showing to the user that it ran yesterday.">
+        Checked yesterday
+      </message>
+      <message name="IDS_SAFETY_CHECK_TIMESTAMP_AFTER_DAYS" desc="A message shown on the safety check page, showing to the user how many days ago it ran.">
+        {NUM_DAYS, plural,
+        =1 {Checked 1 day ago}
+        other {Checked # days ago}}
+      </message>
 
        <!-- Security preferences -->
       <message name="IDS_PREFS_SECURITY_TITLE" desc="Title for the Security preferences. [CHAR-LIMIT=32]">

chrome/browser/ui/android/strings/android_chrome_strings_grd/IDS_SAFETY_CHECK_TIMESTAMP_AFTER.png.sha1

+d60eb18ae9a2dbdd207562bc3a876d9f21ca71ec
\ No newline at end of file

chrome/browser/ui/android/strings/android_chrome_strings_grd/IDS_SAFETY_CHECK_TIMESTAMP_AFTER_DAYS.png.sha1

+c19df76c93c8342fb8bcdc8b03c0b5a3eed5a9d4
\ No newline at end of file

chrome/browser/ui/android/strings/android_chrome_strings_grd/IDS_SAFETY_CHECK_TIMESTAMP_AFTER_HOURS.png.sha1

+a99bb9f7131213f8298e692314215a6a3287e3d0
\ No newline at end of file

chrome/browser/ui/android/strings/android_chrome_strings_grd/IDS_SAFETY_CHECK_TIMESTAMP_AFTER_MINS.png.sha1

+883b04110940c16daf4b46f391b60fae8e477549
\ No newline at end of file

chrome/browser/ui/android/strings/android_chrome_strings_grd/IDS_SAFETY_CHECK_TIMESTAMP_AFTER_YESTERDAY.png.sha1

+7f8b659b27ac25b8239fae599680b9a55262a514
\ No newline at end of file

ui/android/java/src/org/chromium/ui/modelutil/PropertyModel.java

@@ -151,6 +151,42 @@ public class PropertyModel extends PropertyObservable<PropertyKey> {
         }
     }
 
+    /** The key type for read-only long model properties. */
+    public static class ReadableLongPropertyKey extends NamedPropertyKey {
+        /**
+         * Constructs a new unnamed read-only long property key.
+         */
+        public ReadableLongPropertyKey() {
+            this(null);
+        }
+
+        /**
+         * Constructs a new named read-only long property key, e.g. for use in debugging.
+         * @param name The optional name of the property.
+         */
+        public ReadableLongPropertyKey(@Nullable String name) {
+            super(name);
+        }
+    }
+
+    /** The key type for mutable int model properties. */
+    public static final class WritableLongPropertyKey extends ReadableLongPropertyKey {
+        /**
+         * Constructs a new unnamed writable long property key.
+         */
+        public WritableLongPropertyKey() {
+            this(null);
+        }
+
+        /**
+         * Constructs a new named writable long property key, e.g. for use in debugging.
+         * @param name The optional name of the property.
+         */
+        public WritableLongPropertyKey(@Nullable String name) {
+            super(name);
+        }
+    }
+
     /**
      * The key type for read-only Object model properties.
      *
@@ -296,6 +332,32 @@ public class PropertyModel extends PropertyObservable<PropertyKey> {
         notifyPropertyChanged(key);
     }
 
+    /**
+     * Get the current value from the long based key.
+     */
+    public long get(ReadableLongPropertyKey key) {
+        validateKey(key);
+        LongContainer container = (LongContainer) mData.get(key);
+        return container == null ? 0 : container.value;
+    }
+
+    /**
+     * Set the value for the long based key.
+     */
+    public void set(WritableLongPropertyKey key, long value) {
+        validateKey(key);
+        LongContainer container = (LongContainer) mData.get(key);
+        if (container == null) {
+            container = new LongContainer();
+            mData.put(key, container);
+        } else if (container.value == value) {
+            return;
+        }
+
+        container.value = value;
+        notifyPropertyChanged(key);
+    }
+
     /**
      * Get the current value from the boolean based key.
      */
@@ -425,6 +487,14 @@ public class PropertyModel extends PropertyObservable<PropertyKey> {
             return this;
         }
 
+        public Builder with(ReadableLongPropertyKey key, long value) {
+            validateKey(key);
+            LongContainer container = new LongContainer();
+            container.value = value;
+            mData.put(key, container);
+            return this;
+        }
+
         public Builder with(ReadableBooleanPropertyKey key, boolean value) {
             validateKey(key);
             BooleanContainer container = new BooleanContainer();
@@ -525,6 +595,21 @@ public class PropertyModel extends PropertyObservable<PropertyKey> {
         }
     }
 
+    private static class LongContainer extends ValueContainer {
+        public long value;
+
+        @Override
+        public String toString() {
+            return value + " in " + super.toString();
+        }
+
+        @Override
+        public boolean equals(Object other) {
+            return other != null && other instanceof LongContainer
+                    && ((LongContainer) other).value == value;
+        }
+    }
+
     private static class BooleanContainer extends ValueContainer {
         public boolean value;