[Paint Preview] Disable toolbar hide on scroll when Paint Preview showing

This CL introduces the new PaintPreviewWindowAndroidHelper class. This
class stores activity-specific variables in PaintPreviewHelper. Using
the BrowserControlsManager class, it makes the top toolbar persistent
when a Paint Preview is shown.

This CL also fixes a bug where TabbedPaintPreviewPlayer#onDismiss was
never called.

Bug: 1131497
Change-Id: I3caf7017f601536ba03c1e1c60c9b024917f6063
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2425433
Commit-Queue: Mehran Mahmoudi <mahmoudi@chromium.org>
Reviewed-by: Calder Kitagawa <ckitagawa@chromium.org>
Cr-Commit-Position: refs/heads/master@{#810838}

chrome/android/java/src/org/chromium/chrome/browser/paint_preview/PaintPreviewHelper.java

@@ -4,11 +4,15 @@
 
 package org.chromium.chrome.browser.paint_preview;
 
+import android.app.Activity;
 import android.os.SystemClock;
 
+import org.chromium.base.ActivityState;
+import org.chromium.base.ApplicationStatus;
 import org.chromium.chrome.browser.app.ChromeActivity;
 import org.chromium.chrome.browser.flags.CachedFeatureFlags;
 import org.chromium.chrome.browser.flags.ChromeFeatureList;
+import org.chromium.chrome.browser.fullscreen.BrowserControlsManager;
 import org.chromium.chrome.browser.metrics.PageLoadMetrics;
 import org.chromium.chrome.browser.metrics.UmaUtils;
 import org.chromium.chrome.browser.multiwindow.MultiWindowUtils;
@@ -18,6 +22,10 @@ import org.chromium.chrome.browser.tabmodel.EmptyTabModelSelectorObserver;
 import org.chromium.chrome.browser.tabmodel.TabModelSelector;
 import org.chromium.chrome.browser.util.ChromeAccessibilityUtil;
 import org.chromium.content_public.browser.WebContents;
+import org.chromium.ui.base.WindowAndroid;
+
+import java.util.HashMap;
+import java.util.Map;
 
 /**
  * Handles initialization of the Paint Preview tab observers.
@@ -31,9 +39,12 @@ public class PaintPreviewHelper {
     private static boolean sHasAttemptedToShowOnRestore;
 
     /**
-     * Tracks the activity creation time in ms from {@link SystemClock#elapsedRealtime}.
+     * A map for keeping Activity-specific variables and classes. New entries are added on calls
+     * to {@link #initialize(ChromeActivity, TabModelSelector)}. Entries are automatically removed
+     * when their respective Activity is destroyed.
      */
-    private static long sActivityCreationTimeMs;
+    private static Map<WindowAndroid, PaintPreviewWindowAndroidHelper> sWindowAndroidHelperMap =
+            new HashMap<>();
 
     /**
      * Initializes the logic required for the Paint Preview on startup feature. Mainly, observes a
@@ -41,13 +52,14 @@ public class PaintPreviewHelper {
      * @param activity The ChromeActivity that corresponds to the tabModelSelector.
      * @param tabModelSelector The TabModelSelector to observe.
      */
-    public static void initialize(ChromeActivity activity, TabModelSelector tabModelSelector) {
+    public static void initialize(ChromeActivity<?> activity, TabModelSelector tabModelSelector) {
         if (!CachedFeatureFlags.isEnabled(ChromeFeatureList.PAINT_PREVIEW_SHOW_ON_STARTUP)) return;
 
         if (!MultiWindowUtils.getInstance().areMultipleChromeInstancesRunning(activity)) {
             sHasAttemptedToShowOnRestore = false;
         }
-        sActivityCreationTimeMs = activity.getOnCreateTimestampMs();
+        sWindowAndroidHelperMap.put(
+                activity.getWindowAndroid(), new PaintPreviewWindowAndroidHelper(activity));
 
         // TODO(crbug/1074428): verify this doesn't cause a memory leak if the user exits Chrome
         // prior to onTabStateInitialized being called.
@@ -66,22 +78,23 @@ public class PaintPreviewHelper {
     }
 
     /**
-     * Attempts to display the Paint Preview representation of for the given Tab.
-     * @param onShown The callback for when the Paint Preview is shown.
-     * @param onDismissed The callback for when the Paint Preview is dismissed.
-     * @return Whether the Paint Preview started to initialize or is already initializating.
-     * Note that if the Paint Preview is already showing, this will return false.
+     * Attempts to display the Paint Preview representation for the given Tab.
      */
-    public static boolean showPaintPreviewOnRestore(Tab tab) {
+    public static void showPaintPreviewOnRestore(Tab tab) {
         if (!CachedFeatureFlags.isEnabled(ChromeFeatureList.PAINT_PREVIEW_SHOW_ON_STARTUP)
                 || sHasAttemptedToShowOnRestore
                 || ChromeAccessibilityUtil.get().isAccessibilityEnabled()) {
-            return false;
+            return;
         }
 
-        sHasAttemptedToShowOnRestore = true;
+        PaintPreviewWindowAndroidHelper windowAndroidHelper =
+                sWindowAndroidHelperMap.get(tab.getWindowAndroid());
+        if (windowAndroidHelper == null) return;
 
+        sHasAttemptedToShowOnRestore = true;
         TabbedPaintPreviewPlayer player = TabbedPaintPreviewPlayer.get(tab);
+        player.setBrowserVisibilityDelegate(
+                windowAndroidHelper.getBrowserControlsManager().getBrowserVisibilityDelegate());
         PageLoadMetrics.Observer observer = new PageLoadMetrics.Observer() {
             @Override
             public void onFirstMeaningfulPaint(WebContents webContents, long navigationId,
@@ -90,16 +103,49 @@ public class PaintPreviewHelper {
             }
         };
 
-        if (!player.maybeShow(() -> {
-                PageLoadMetrics.removeObserver(observer);
-            }, sActivityCreationTimeMs, () -> {
-                return UmaUtils.hasComeToForeground() && !UmaUtils.hasComeToBackground();
-            })) {
-            return false;
+        if (!player.maybeShow(()
+                                      -> PageLoadMetrics.removeObserver(observer),
+                    windowAndroidHelper.getActivityCreationTime(),
+                    () -> UmaUtils.hasComeToForeground() && !UmaUtils.hasComeToBackground())) {
+            return;
         }
 
         PageLoadMetrics.addObserver(observer);
+    }
 
-        return true;
+    /**
+     * A helper class for keeping activity-specific variables and classes.
+     */
+    private static class PaintPreviewWindowAndroidHelper
+            implements ApplicationStatus.ActivityStateListener {
+        /**
+         * Tracks the activity creation time in ms from {@link SystemClock#elapsedRealtime}.
+         */
+        private long mActivityCreationTime;
+        private WindowAndroid mWindowAndroid;
+        private BrowserControlsManager mBrowserControlsManager;
+
+        PaintPreviewWindowAndroidHelper(ChromeActivity<?> chromeActivity) {
+            mWindowAndroid = chromeActivity.getWindowAndroid();
+            mActivityCreationTime = chromeActivity.getOnCreateTimestampMs();
+            mBrowserControlsManager = chromeActivity.getBrowserControlsManager();
+            ApplicationStatus.registerStateListenerForActivity(this, chromeActivity);
+        }
+
+        long getActivityCreationTime() {
+            return mActivityCreationTime;
+        }
+
+        BrowserControlsManager getBrowserControlsManager() {
+            return mBrowserControlsManager;
+        }
+
+        @Override
+        public void onActivityStateChange(Activity activity, @ActivityState int newState) {
+            if (newState == ActivityState.DESTROYED) {
+                sWindowAndroidHelperMap.remove(mWindowAndroid);
+                ApplicationStatus.unregisterActivityStateListener(this);
+            }
+        }
     }
 }

chrome/browser/paint_preview/android/BUILD.gn

@@ -34,6 +34,7 @@ android_library("java") {
     "//base:base_java",
     "//base:jni_java",
     "//chrome/browser/android/lifecycle:java",
+    "//chrome/browser/browser_controls/android:java",
     "//chrome/browser/flags:java",
     "//chrome/browser/tab:java",
     "//chrome/browser/tabmodel:java",

chrome/browser/paint_preview/android/java/src/org/chromium/chrome/browser/paint_preview/TabbedPaintPreviewPlayer.java

@@ -15,6 +15,7 @@ import android.view.View;
 import androidx.annotation.Nullable;
 
 import org.chromium.base.UserData;
+import org.chromium.chrome.browser.browser_controls.BrowserStateBrowserControlsVisibilityDelegate;
 import org.chromium.chrome.browser.flags.ChromeFeatureList;
 import org.chromium.chrome.browser.paint_preview.TabbedPaintPreviewMetricsHelper.ExitCause;
 import org.chromium.chrome.browser.paint_preview.services.PaintPreviewTabService;
@@ -31,6 +32,7 @@ import org.chromium.components.paintpreview.player.PlayerManager;
 import org.chromium.content_public.browser.LoadUrlParams;
 import org.chromium.content_public.browser.NavigationHandle;
 import org.chromium.content_public.browser.WebContents;
+import org.chromium.ui.util.TokenHolder;
 import org.chromium.url.GURL;
 
 import java.util.concurrent.Callable;
@@ -61,6 +63,8 @@ public class TabbedPaintPreviewPlayer implements TabViewProvider, UserData {
     private boolean mFadingOut;
     private int mSnackbarShownCount;
     private TabbedPaintPreviewMetricsHelper mMetricsHelper;
+    private BrowserStateBrowserControlsVisibilityDelegate mBrowserVisibilityDelegate;
+    private int mPersistentToolbarToken = TokenHolder.INVALID_TOKEN;
 
     public static TabbedPaintPreviewPlayer get(Tab tab) {
         if (tab.getUserDataHost().getUserData(USER_DATA_KEY) == null) {
@@ -116,6 +120,8 @@ public class TabbedPaintPreviewPlayer implements TabViewProvider, UserData {
 
         @Override
         public void onHidden(Tab tab, @TabHidingType int hidingType) {
+            releasePersistentToolbar();
+
             if (mPlayerManager == null || !isShowingAndNeedsBadge()) return;
 
             // If the tab is hidden as a result of pausing the activity we shouldn't remove it.
@@ -123,6 +129,11 @@ public class TabbedPaintPreviewPlayer implements TabViewProvider, UserData {
 
             removePaintPreview(ExitCause.TAB_HIDDEN);
         }
+
+        @Override
+        public void onShown(Tab tab, int type) {
+            if (isShowingAndNeedsBadge()) showToolbarPersistent();
+        }
     }
 
     private TabbedPaintPreviewPlayer(Tab tab) {
@@ -133,6 +144,11 @@ public class TabbedPaintPreviewPlayer implements TabViewProvider, UserData {
         mTab.addObserver(mObserver);
     }
 
+    public void setBrowserVisibilityDelegate(
+            BrowserStateBrowserControlsVisibilityDelegate browserVisibilityDelegate) {
+        mBrowserVisibilityDelegate = browserVisibilityDelegate;
+    }
+
     /**
      * Triggered via {@link PageLoadMetrics.Observer} when First Meaningful Paint happens.
      * @param webContents the webContents that triggered the event.
@@ -207,11 +223,12 @@ public class TabbedPaintPreviewPlayer implements TabViewProvider, UserData {
      */
     private void removePaintPreview(@ExitCause int exitCause) {
         PaintPreviewCompositorUtils.stopWarmCompositor();
-        mOnDismissed = null;
         mInitializing = false;
         if (mTab == null || mPlayerManager == null || mFadingOut) return;
 
         mFadingOut = true;
+        if (mOnDismissed != null) mOnDismissed.run();
+        mOnDismissed = null;
         Point scrollPosition = mPlayerManager.getScrollPosition();
         if (mTab.getWebContents() != null && scrollPosition != null) {
             mTab.getWebContents().getEventForwarder().scrollTo(scrollPosition.x, scrollPosition.y);
@@ -276,6 +293,25 @@ public class TabbedPaintPreviewPlayer implements TabViewProvider, UserData {
         mTab.loadUrl(new LoadUrlParams(url.getSpec()));
     }
 
+    /**
+     * Persistently shows the toolbar and avoids hiding it on scrolling down.
+     */
+    private void showToolbarPersistent() {
+        if (mBrowserVisibilityDelegate == null
+                || mPersistentToolbarToken != TokenHolder.INVALID_TOKEN) {
+            return;
+        }
+
+        mPersistentToolbarToken = mBrowserVisibilityDelegate.showControlsPersistent();
+    }
+
+    private void releasePersistentToolbar() {
+        if (mBrowserVisibilityDelegate == null) return;
+
+        mBrowserVisibilityDelegate.releasePersistentShowingToken(mPersistentToolbarToken);
+        mPersistentToolbarToken = TokenHolder.INVALID_TOKEN;
+    }
+
     @Override
     public int getTabViewProviderType() {
         return Type.PAINT_PREVIEW;
@@ -286,9 +322,14 @@ public class TabbedPaintPreviewPlayer implements TabViewProvider, UserData {
         return mPlayerManager == null ? null : mPlayerManager.getView();
     }
 
+    @Override
+    public void onShown() {
+        showToolbarPersistent();
+    }
+
     @Override
     public void onHidden() {
-        if (mOnDismissed != null) mOnDismissed.run();
+        releasePersistentToolbar();
     }
 
     @Override