Detect Suggestion list height / respond to keyboard visibility change

This change is part of Adaptive Suggestions Count feature that aims
at presenting as many suggestions on screen as would fit between the
Omnibox and soft keyboard.

The change introduces no new logic and simply installs a callback
that monitors and responds to suggestion list size changes.

Bug: 1050813
Change-Id: I8fe777c83241cdb47e9cf238fe246b25cdbf78cc
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2067659
Commit-Queue: Ender <ender@google.com>
Reviewed-by: Ted Choc <tedchoc@chromium.org>
Reviewed-by: Patrick Noland <pnoland@chromium.org>
Cr-Commit-Position: refs/heads/master@{#744915}

chrome/android/java/src/org/chromium/chrome/browser/omnibox/suggestions/AutocompleteCoordinatorImpl.java

@@ -67,20 +67,21 @@ public class AutocompleteCoordinatorImpl implements AutocompleteCoordinator {
         Context context = parent.getContext();
 
         PropertyModel listModel = new PropertyModel(SuggestionListProperties.ALL_KEYS);
+        ModelList listItems = new ModelList();
+        mMediator =
+                new AutocompleteMediator(context, delegate, urlBarEditingTextProvider, listModel);
+
         listModel.set(SuggestionListProperties.EMBEDDER, listEmbedder);
         listModel.set(SuggestionListProperties.VISIBLE, false);
-
-        ModelList listItems = new ModelList();
+        listModel.set(SuggestionListProperties.OBSERVER, mMediator);
         listModel.set(SuggestionListProperties.SUGGESTION_MODELS, listItems);
+
         ViewProvider<SuggestionListViewHolder> viewProvider =
                 createViewProvider(context, listItems);
         viewProvider.whenLoaded((holder) -> { mListView = holder.listView; });
         LazyConstructionPropertyMcp.create(listModel, SuggestionListProperties.VISIBLE,
                 viewProvider, SuggestionListViewBinder::bind);
 
-        mMediator =
-                new AutocompleteMediator(context, delegate, urlBarEditingTextProvider, listModel);
-
         // https://crbug.com/966227 Set initial layout direction ahead of inflating the suggestions.
         updateSuggestionListLayoutDirection();
     }

chrome/android/java/src/org/chromium/chrome/browser/omnibox/suggestions/AutocompleteMediator.java

@@ -28,6 +28,7 @@ import org.chromium.chrome.browser.GlobalDiscardableReferencePool;
 import org.chromium.chrome.browser.compositor.layouts.EmptyOverviewModeObserver;
 import org.chromium.chrome.browser.compositor.layouts.OverviewModeBehavior;
 import org.chromium.chrome.browser.favicon.LargeIconBridge;
+import org.chromium.chrome.browser.flags.ChromeFeatureList;
 import org.chromium.chrome.browser.image_fetcher.ImageFetcher;
 import org.chromium.chrome.browser.image_fetcher.ImageFetcherConfig;
 import org.chromium.chrome.browser.image_fetcher.ImageFetcherFactory;
@@ -37,6 +38,7 @@ import org.chromium.chrome.browser.lifecycle.StartStopWithNativeObserver;
 import org.chromium.chrome.browser.omnibox.OmniboxSuggestionType;
 import org.chromium.chrome.browser.omnibox.UrlBarEditingTextStateProvider;
 import org.chromium.chrome.browser.omnibox.suggestions.AutocompleteController.OnSuggestionsReceivedListener;
+import org.chromium.chrome.browser.omnibox.suggestions.SuggestionListProperties.SuggestionListObserver;
 import org.chromium.chrome.browser.omnibox.suggestions.answer.AnswerSuggestionProcessor;
 import org.chromium.chrome.browser.omnibox.suggestions.basic.BasicSuggestionProcessor;
 import org.chromium.chrome.browser.omnibox.suggestions.basic.SuggestionHost;
@@ -68,8 +70,8 @@ import java.util.List;
 /**
  * Handles updating the model state for the currently visible omnibox suggestions.
  */
-class AutocompleteMediator
-        implements OnSuggestionsReceivedListener, SuggestionHost, StartStopWithNativeObserver {
+class AutocompleteMediator implements OnSuggestionsReceivedListener, SuggestionHost,
+                                      StartStopWithNativeObserver, SuggestionListObserver {
     /** A struct containing information about the suggestion and its view type. */
     private static class SuggestionViewInfo {
         /** Processor managing the suggestion. */
@@ -119,6 +121,7 @@ class AutocompleteMediator
     private boolean mNativeInitialized;
     private AutocompleteController mAutocomplete;
     private long mUrlFocusTime;
+    private boolean mEnableAdaptiveSuggestionsCount;
 
     @IntDef({SuggestionVisibilityState.DISALLOWED, SuggestionVisibilityState.PENDING_ALLOW,
             SuggestionVisibilityState.ALLOWED})
@@ -432,6 +435,9 @@ class AutocompleteMediator
     void onNativeInitialized() {
         mNativeInitialized = true;
 
+        mEnableAdaptiveSuggestionsCount =
+                ChromeFeatureList.isEnabled(ChromeFeatureList.OMNIBOX_ADAPTIVE_SUGGESTIONS_COUNT);
+
         for (Runnable deferredRunnable : mDeferredNativeRunnables) {
             mHandler.post(deferredRunnable);
         }
@@ -1157,4 +1163,17 @@ class AutocompleteMediator
             return mShouldLog;
         }
     }
+
+    /**
+     * Respond to Suggestion list height change and update list of presented suggestions.
+     *
+     * This typically happens as a result of soft keyboard being shown or hidden.
+     *
+     * @param newHeightPx New height of the suggestion list in pixels.
+     */
+    @Override
+    public void onSuggestionListHeightChanged(int newHeightPx) {
+        if (!mEnableAdaptiveSuggestionsCount) return;
+        // TODO(crbug.com/1050813): Update visibility of loaded suggestions.
+    }
 }

chrome/android/java/src/org/chromium/chrome/browser/omnibox/suggestions/OmniboxSuggestionsList.java

@@ -23,9 +23,12 @@ import android.widget.ListView;
 import androidx.annotation.VisibleForTesting;
 
 import org.chromium.base.TraceEvent;
+import org.chromium.base.task.PostTask;
 import org.chromium.chrome.R;
+import org.chromium.chrome.browser.omnibox.suggestions.SuggestionListProperties.SuggestionListObserver;
 import org.chromium.chrome.browser.util.KeyNavigationUtil;
 import org.chromium.components.browser_ui.styles.ChromeColors;
+import org.chromium.content_public.browser.UiThreadTaskTraits;
 import org.chromium.ui.base.ViewUtils;
 
 import java.util.ArrayList;
@@ -43,8 +46,11 @@ public class OmniboxSuggestionsList extends ListView {
     private OmniboxSuggestionListEmbedder mEmbedder;
     private View mAnchorView;
     private View mAlignmentView;
+    private SuggestionListObserver mObserver;
     private OnGlobalLayoutListener mAnchorViewLayoutListener;
     private OnLayoutChangeListener mAlignmentViewLayoutListener;
+    private int mListViewMaxHeight;
+    private int mLastBroadcastedListViewMaxHeight;
 
     /**
      * Constructs a new list designed for containing omnibox suggestions.
@@ -106,6 +112,10 @@ public class OmniboxSuggestionsList extends ListView {
         }
     }
 
+    void setObserver(SuggestionListObserver observer) {
+        mObserver = observer;
+    }
+
     private void adjustSidePadding() {
         if (mAlignmentView == null) return;
 
@@ -162,6 +172,24 @@ public class OmniboxSuggestionsList extends ListView {
             mEmbedder.getWindowDelegate().getWindowVisibleDisplayFrame(mTempRect);
             int availableViewportHeight = mTempRect.height() - anchorBottomRelativeToContent;
 
+            if (availableViewportHeight != mListViewMaxHeight) {
+                mListViewMaxHeight = availableViewportHeight;
+                if (mObserver != null) {
+                    PostTask.postTask(UiThreadTaskTraits.DEFAULT, () -> {
+                        // Detect if there was another change since this task posted.
+                        // This indicates a subsequent task being posted too.
+                        if (mListViewMaxHeight != availableViewportHeight) return;
+                        // Detect if the new height is the same as previously broadcasted.
+                        // The two checks (one above and one below) allow us to detect quick
+                        // A->B->A transitions and suppress the broadcasts.
+                        if (mLastBroadcastedListViewMaxHeight == availableViewportHeight) return;
+                        if (mObserver == null) return;
+                        mObserver.onSuggestionListHeightChanged(availableViewportHeight);
+                        mLastBroadcastedListViewMaxHeight = availableViewportHeight;
+                    });
+                }
+            }
+
             super.onMeasure(MeasureSpec.makeMeasureSpec(
                                     mAnchorView.getMeasuredWidth(), MeasureSpec.EXACTLY),
                     MeasureSpec.makeMeasureSpec(availableViewportHeight,

chrome/android/java/src/org/chromium/chrome/browser/omnibox/suggestions/SuggestionListProperties.java

@@ -13,6 +13,19 @@ import org.chromium.ui.modelutil.PropertyModel.WritableObjectPropertyKey;
  * The properties controlling the state of the list of suggestion items.
  */
 public class SuggestionListProperties {
+    /**
+     * Interface that will receive notifications and callbacks from OmniboxSuggestionList.
+     */
+    public interface SuggestionListObserver {
+        /**
+         * Invoked whenever the height of suggestion list changes.
+         * The height may change as a result of eg. soft keyboard popping up.
+         *
+         * @param newHeightPx New height of the suggestion list in pixels.
+         */
+        void onSuggestionListHeightChanged(int newHeightPx);
+    }
+
     /** Whether the suggestion list is visible. */
     public static final WritableBooleanPropertyKey VISIBLE = new WritableBooleanPropertyKey();
 
@@ -30,6 +43,10 @@ public class SuggestionListProperties {
     /** Whether the suggestion list should have a dark background. */
     public static final WritableBooleanPropertyKey IS_INCOGNITO = new WritableBooleanPropertyKey();
 
+    /** Observer that will receive notifications and callbacks from Suggestion List. */
+    public static final WritableObjectPropertyKey<SuggestionListObserver> OBSERVER =
+            new WritableObjectPropertyKey<>();
+
     public static final PropertyKey[] ALL_KEYS =
-            new PropertyKey[] {VISIBLE, EMBEDDER, SUGGESTION_MODELS, IS_INCOGNITO};
+            new PropertyKey[] {VISIBLE, EMBEDDER, SUGGESTION_MODELS, IS_INCOGNITO, OBSERVER};
 }

chrome/android/java/src/org/chromium/chrome/browser/omnibox/suggestions/SuggestionListViewBinder.java

@@ -51,6 +51,8 @@ class SuggestionListViewBinder {
             }
         } else if (SuggestionListProperties.EMBEDDER.equals(propertyKey)) {
             view.listView.setEmbedder(model.get(SuggestionListProperties.EMBEDDER));
+        } else if (SuggestionListProperties.OBSERVER.equals(propertyKey)) {
+            view.listView.setObserver(model.get(SuggestionListProperties.OBSERVER));
         } else if (SuggestionListProperties.SUGGESTION_MODELS.equals(propertyKey)) {
             // This should only ever be bound once.
             model.get(SuggestionListProperties.SUGGESTION_MODELS)