[Messages] Introduce MessageDispatcher

This CL:
- Introduces MessageDispatcher and its implementation
- Makes it available through WindowAndroid, following the pattern of
  BottomSheetController
- Refactors MessageQueueManager removing it from public messages target

BUG=1123947
R=lazzzis@chromium.org

Change-Id: Ieeece06f4b2f6b31abfd9c6cfd8df5b428076f8d
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2446195Reviewed-by: Theresa  <twellington@chromium.org>
Commit-Queue: Pavel Yatsuk <pavely@chromium.org>
Cr-Commit-Position: refs/heads/master@{#815879}

chrome/android/BUILD.gn

@@ -418,6 +418,7 @@ android_library("chrome_java") {
     "//components/media_router/browser/android:java",
     "//components/messages/android:factory_java",
     "//components/messages/android:java",
+    "//components/messages/android:manager_java",
     "//components/minidump_uploader:minidump_uploader_java",
     "//components/module_installer/android:module_installer_java",
     "//components/module_installer/android:module_interface_java",

chrome/android/java/src/org/chromium/chrome/browser/ui/RootUiCoordinator.java

@@ -81,7 +81,7 @@ import org.chromium.components.browser_ui.bottomsheet.ManagedBottomSheetControll
 import org.chromium.components.browser_ui.widget.MenuOrKeyboardActionController;
 import org.chromium.components.browser_ui.widget.scrim.ScrimCoordinator;
 import org.chromium.components.feature_engagement.EventConstants;
-import org.chromium.components.messages.MessageQueueManager;
+import org.chromium.components.messages.ManagedMessageDispatcher;
 import org.chromium.components.messages.MessagesFactory;
 import org.chromium.content_public.browser.ActionModeCallbackHelper;
 import org.chromium.content_public.browser.LoadUrlParams;
@@ -158,7 +158,7 @@ public class RootUiCoordinator
     private ObservableSupplier<TabModelSelector> mTabModelSelectorSupplier;
     private final OneshotSupplier<StartSurface> mStartSurfaceSupplier;
     @Nullable
-    private MessageQueueManager mMessageQueueManager;
+    private ManagedMessageDispatcher mMessageDispatcher;
 
     /**
      * Create a new {@link RootUiCoordinator} for the given activity.
@@ -215,11 +215,6 @@ public class RootUiCoordinator
         mOverviewModeBehaviorSupplier.onAvailable(
                 mCallbackController.makeCancelable(this::setOverviewModeBehavior));
         mStartSurfaceSupplier = startSurfaceSupplier;
-
-        if (CachedFeatureFlags.isEnabled(ChromeFeatureList.MESSAGES_FOR_ANDROID_INFRASTRUCTURE)) {
-            mMessageQueueManager =
-                    MessagesFactory.createMessageQueueManager(mActivity.getWindowAndroid());
-        }
     }
 
     // TODO(pnoland, crbug.com/865801): remove this in favor of wiring it directly.
@@ -234,9 +229,9 @@ public class RootUiCoordinator
 
         mActivity.getLayoutManagerSupplier().removeObserver(mLayoutManagerSupplierCallback);
 
-        if (mMessageQueueManager != null) {
-            mMessageQueueManager.destroy();
-            mMessageQueueManager = null;
+        if (mMessageDispatcher != null) {
+            MessagesFactory.detachMessageDispatcher(mMessageDispatcher);
+            mMessageDispatcher = null;
         }
 
         if (mOverlayPanelManager != null) {
@@ -321,6 +316,12 @@ public class RootUiCoordinator
 
         initFindToolbarManager();
         initializeToolbar();
+        if (CachedFeatureFlags.isEnabled(ChromeFeatureList.MESSAGES_FOR_ANDROID_INFRASTRUCTURE)) {
+            mMessageDispatcher = MessagesFactory.createMessageDispatcher(
+                    mActivity.findViewById(R.id.message_container));
+            MessagesFactory.attachMessageDispatcher(
+                    mActivity.getWindowAndroid(), mMessageDispatcher);
+        }
     }
 
     @Override

components/messages/android/BUILD.gn

@@ -11,7 +11,8 @@ android_library("java") {
     "java/src/org/chromium/components/messages/MessageBannerView.java",
     "java/src/org/chromium/components/messages/MessageBannerViewBinder.java",
     "java/src/org/chromium/components/messages/MessageContainer.java",
-    "java/src/org/chromium/components/messages/MessageQueueManager.java",
+    "java/src/org/chromium/components/messages/MessageDispatcher.java",
+    "java/src/org/chromium/components/messages/MessageDispatcherProvider.java",
     "java/src/org/chromium/components/messages/MessageStateHandler.java",
     "java/src/org/chromium/components/messages/SingleActionMessage.java",
   ]
@@ -38,6 +39,15 @@ android_resources("java_resources") {
   ]
 }
 
+# Build target for Messages manager code, that owns and initializes
+# MessageDispatcher.
+android_library("manager_java") {
+  sources = [
+    "java/src/org/chromium/components/messages/ManagedMessageDispatcher.java",
+  ]
+  deps = [ ":java" ]
+}
+
 static_library("feature_flags") {
   sources = [
     "messages_feature.cc",
@@ -79,6 +89,7 @@ android_library_factory("factory_java") {
 
   deps = [
     ":java",
+    ":manager_java",
     "//ui/android:ui_full_java",
   ]
 }

components/messages/android/internal/BUILD.gn

@@ -6,12 +6,14 @@ import("//build/config/android/rules.gni")
 
 android_library("java") {
   sources = [
-    "java/src/org/chromium/components/messages/MessageQueueManagerImpl.java",
+    "java/src/org/chromium/components/messages/MessageDispatcherImpl.java",
+    "java/src/org/chromium/components/messages/MessageQueueManager.java",
     "java/src/org/chromium/components/messages/MessagesFactory.java",
   ]
 
   deps = [
     "..:java",
+    "..:manager_java",
     "//base:base_java",
     "//third_party/android_deps:androidx_annotation_annotation_java",
     "//ui/android:ui_full_java",
@@ -22,7 +24,9 @@ java_library("junit") {
   # Skip platform checks since Robolectric depends on requires_android targets.
   bypass_platform_checks = true
   testonly = true
-  sources = [ "java/src/org/chromium/components/messages/MessageQueueManagerImplTest.java" ]
+  sources = [
+    "java/src/org/chromium/components/messages/MessageQueueManagerTest.java",
+  ]
   deps = [
     ":java",
     "..:java",

components/messages/android/internal/java/src/org/chromium/components/messages/MessageDispatcherImpl.java

+// 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.
+
+package org.chromium.components.messages;
+
+import org.chromium.ui.modelutil.PropertyModel;
+
+/**
+ * This class implements public MessageDispatcher interface, delegating the actual work to
+ * MessageQueueManager.
+ */
+public class MessageDispatcherImpl implements ManagedMessageDispatcher {
+    private final MessageQueueManager mMessageQueueManager = new MessageQueueManager();
+    private final MessageContainer mMessageContainer;
+
+    /**
+     * Build a new message dispatcher
+     * @param messageContainer A container view for displaying message banners.
+     */
+    public MessageDispatcherImpl(MessageContainer messageContainer) {
+        mMessageContainer = messageContainer;
+    }
+
+    @Override
+    public void enqueueMessage(PropertyModel messageProperties) {
+        MessageStateHandler messageStateHandler =
+                new SingleActionMessage(mMessageContainer, messageProperties);
+        mMessageQueueManager.enqueueMessage(messageStateHandler, messageProperties);
+    }
+
+    @Override
+    public void dismissMessage(PropertyModel messageProperties) {
+        mMessageQueueManager.dismissMessage(messageProperties);
+    }
+}

components/messages/android/internal/java/src/org/chromium/components/messages/MessageQueueManagerImpl.java → components/messages/android/internal/java/src/org/chromium/components/messages/MessageQueueManager.java

@@ -6,10 +6,6 @@ package org.chromium.components.messages;
 
 import androidx.annotation.Nullable;
 
-import org.chromium.base.UnownedUserData;
-import org.chromium.base.UnownedUserDataKey;
-import org.chromium.ui.base.WindowAndroid;
-
 import java.util.ArrayDeque;
 import java.util.HashMap;
 import java.util.Map;
@@ -19,42 +15,13 @@ import java.util.Queue;
  * A class managing the queue of messages. Its primary role is to decide when to show/hide current
  * message and which message to show next.
  */
-class MessageQueueManagerImpl implements MessageQueueManager, UnownedUserData {
-    private static final UnownedUserDataKey<MessageQueueManagerImpl> KEY =
-            new UnownedUserDataKey<>(MessageQueueManagerImpl.class);
-
+class MessageQueueManager {
     private final Queue<MessageStateHandler> mMessageQueue = new ArrayDeque<>();
     private final Map<Object, MessageStateHandler> mMessageMap = new HashMap<>();
     @Nullable
     private MessageStateHandler mCurrentDisplayedMessage;
 
-    /**
-     * Get the activity's MessageQueueManager from the provided WindowAndroid.
-     * @param window The window to get the manager from.
-     * @return The activity's MessageQueueManager.
-     */
-    public static MessageQueueManagerImpl from(WindowAndroid window) {
-        return KEY.retrieveDataFromHost(window.getUnownedUserDataHost());
-    }
-
-    public MessageQueueManagerImpl() {}
-
-    /**
-     * Attaches MessageQueueManager to a given window. This window will be used later to retrieve
-     * activity's MessageQueueManager.
-     * @param window The window to attach to.
-     */
-    public void attachToWindowAndroid(WindowAndroid window) {
-        KEY.attachToHost(window.getUnownedUserDataHost(), this);
-    }
-
-    /**
-     * Destroys MessageQueueManager, detaching it from the WindowAndroid it was attached to.
-     */
-    @Override
-    public void destroy() {
-        KEY.detachFromAllHosts(this);
-    }
+    public MessageQueueManager() {}
 
     /**
      * Enqueues a message. Associates the message with its key; the key is used later to dismiss the

components/messages/android/internal/java/src/org/chromium/components/messages/MessageQueueManagerImplTest.java → components/messages/android/internal/java/src/org/chromium/components/messages/MessageQueueManagerTest.java

@@ -17,10 +17,10 @@ import org.mockito.Mockito;
 import org.chromium.base.test.BaseRobolectricTestRunner;
 
 /**
- * Unit tests for MessageQueueManagerImpl.
+ * Unit tests for MessageQueueManager.
  */
 @RunWith(BaseRobolectricTestRunner.class)
-public class MessageQueueManagerImplTest {
+public class MessageQueueManagerTest {
     /**
      * Tests lifecycle of a single message:
      *   - enqueueMessage() calls show()
@@ -29,7 +29,7 @@ public class MessageQueueManagerImplTest {
     @Test
     @SmallTest
     public void testEnqueueMessage() {
-        MessageQueueManagerImpl queueManager = new MessageQueueManagerImpl();
+        MessageQueueManager queueManager = new MessageQueueManager();
         MessageStateHandler m1 = Mockito.mock(MessageStateHandler.class);
         MessageStateHandler m2 = Mockito.mock(MessageStateHandler.class);
 
@@ -52,7 +52,7 @@ public class MessageQueueManagerImplTest {
     @Test
     @SmallTest
     public void testOneMessageShownAtATime() {
-        MessageQueueManagerImpl queueManager = new MessageQueueManagerImpl();
+        MessageQueueManager queueManager = new MessageQueueManager();
         MessageStateHandler m1 = Mockito.mock(MessageStateHandler.class);
         MessageStateHandler m2 = Mockito.mock(MessageStateHandler.class);
 
@@ -74,7 +74,7 @@ public class MessageQueueManagerImplTest {
     @Test
     @SmallTest
     public void testDismissBeforeShow() {
-        MessageQueueManagerImpl queueManager = new MessageQueueManagerImpl();
+        MessageQueueManager queueManager = new MessageQueueManager();
         MessageStateHandler m1 = Mockito.mock(MessageStateHandler.class);
         MessageStateHandler m2 = Mockito.mock(MessageStateHandler.class);
 
@@ -98,7 +98,7 @@ public class MessageQueueManagerImplTest {
     @Test(expected = IllegalStateException.class)
     @SmallTest
     public void testEnqueueDuplicateKey() {
-        MessageQueueManagerImpl queueManager = new MessageQueueManagerImpl();
+        MessageQueueManager queueManager = new MessageQueueManager();
         MessageStateHandler m1 = Mockito.mock(MessageStateHandler.class);
         MessageStateHandler m2 = Mockito.mock(MessageStateHandler.class);
         Object key = new Object();
@@ -113,7 +113,7 @@ public class MessageQueueManagerImplTest {
     @Test
     @SmallTest
     public void testDismissMessageTwice() {
-        MessageQueueManagerImpl queueManager = new MessageQueueManagerImpl();
+        MessageQueueManager queueManager = new MessageQueueManager();
         MessageStateHandler m1 = Mockito.mock(MessageStateHandler.class);
         queueManager.enqueueMessage(m1, m1);
         queueManager.dismissMessage(m1);

components/messages/android/internal/java/src/org/chromium/components/messages/MessagesFactory.java

@@ -9,13 +9,29 @@ import org.chromium.ui.base.WindowAndroid;
 /** A factory for constructing different Messages related objects. */
 public class MessagesFactory {
     /**
-     * Creates an instance of MessageQueueManager and attaches it to WindowAndroid.
-     * @param windowAndroid The WindowAndroid to attach MessageQueueManager to.
-     * @return The constructed MessageQueueManager.
+     * Creates an instance of ManagedMessageDispatcher.
+     * @return The constructed ManagedMessageDispatcher.
      */
-    public static MessageQueueManager createMessageQueueManager(WindowAndroid windowAndroid) {
-        MessageQueueManagerImpl messageQueueManager = new MessageQueueManagerImpl();
-        messageQueueManager.attachToWindowAndroid(windowAndroid);
-        return messageQueueManager;
+    public static ManagedMessageDispatcher createMessageDispatcher(MessageContainer container) {
+        return new MessageDispatcherImpl(container);
+    }
+
+    /**
+     * Attaches MessageDispatcher as UnownedUserData to WindowAndroid making it accessible to
+     * components outside of chrome/android.
+     * @param windowAndroid The WindowAndroid to attach ManagedMessageDispatcher to.
+     * @param messageDispatcher The MessageDispatcher to attach.
+     */
+    public static void attachMessageDispatcher(
+            WindowAndroid windowAndroid, ManagedMessageDispatcher messageDispatcher) {
+        MessageDispatcherProvider.attach(windowAndroid, messageDispatcher);
+    }
+
+    /**
+     * Detaches MessageDispatcher from WindowAndroid.
+     * @param messageDispatcher The MessageDispatcher to detach from WindowAndroid.
+     */
+    public static void detachMessageDispatcher(ManagedMessageDispatcher messageDispatcher) {
+        MessageDispatcherProvider.detach(messageDispatcher);
     }
 }

components/messages/android/java/src/org/chromium/components/messages/MessageQueueManager.java → components/messages/android/java/src/org/chromium/components/messages/ManagedMessageDispatcher.java

@@ -5,12 +5,7 @@
 package org.chromium.components.messages;
 
 /**
- * The public interface for managing the queue of messages. The embedder should retain reference to
- * MessageQueueManager and destroy it when the Activity gets destroyed.
+ * An interface for the MessageDispatcher owning object.
  */
-public interface MessageQueueManager {
-    /**
-     * Destroys MessageQueueManager, detaching it from the WindowAndroid it was attached to.
-     */
-    void destroy();
-}
+public interface ManagedMessageDispatcher
+        extends MessageDispatcher, MessageDispatcherProvider.Unowned {}

components/messages/android/java/src/org/chromium/components/messages/MessageDispatcher.java

+// 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.
+
+package org.chromium.components.messages;
+
+import org.chromium.ui.modelutil.PropertyModel;
+
+/**
+ * The public interface for Messages. To interact with messages, feature should obtain a reference
+ * to MessageDispatcher through MessageDispatcherProvider and call methods of MessageDispatcher.
+ */
+public interface MessageDispatcher {
+    /**
+     * Enqueues a message defined by its properties.
+     * @param messageProperties The PropertyModel with message's visual properties.
+     */
+    void enqueueMessage(PropertyModel messageProperties);
+
+    /**
+     * Dismisses a message referenced by its PropertyModel. Hdes the message if it is currently
+     * displayed. Displays the next message in the queue if available.
+     * @param messageProperties The PropertyModel of the messageto be dismissed.
+     */
+    void dismissMessage(PropertyModel messageProperties);
+}

components/messages/android/java/src/org/chromium/components/messages/MessageDispatcherProvider.java

+// 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.
+
+package org.chromium.components.messages;
+
+import org.chromium.base.UnownedUserData;
+import org.chromium.base.UnownedUserDataKey;
+import org.chromium.ui.base.WindowAndroid;
+
+/**
+ * The class that handles association of MessageDispatcher with WindowAndroid and retrieval of the
+ * associated MessageDispatcher.
+ */
+public class MessageDispatcherProvider {
+    /** An interface that allows a MessageDispatcher to be associated with an unowned data host. */
+    interface Unowned extends MessageDispatcher, UnownedUserData {}
+
+    /** The key used to bind the MessageDispatcher to the unowned data host. */
+    private static final UnownedUserDataKey<Unowned> KEY = new UnownedUserDataKey<>(Unowned.class);
+
+    /**
+     * Retrieves the shared MessageDispatcher from the provided WindowAndroid.
+     * @param windowAndroid The window to retrieve MessageDispatcher from.
+     * @return An instance of MessageDispatcher associated with the window.
+     */
+    public static MessageDispatcher from(WindowAndroid windowAndroid) {
+        return KEY.retrieveDataFromHost(windowAndroid.getUnownedUserDataHost());
+    }
+
+    static void attach(WindowAndroid windowAndroid, Unowned controller) {
+        KEY.attachToHost(windowAndroid.getUnownedUserDataHost(), controller);
+    }
+
+    static void detach(Unowned controller) {
+        KEY.detachFromAllHosts(controller);
+    }
+}