chrome/android/features/tab_ui/java/src/org/chromium/chrome/browser/tasks/tab_management/MultiThumbnailCardProvider.java - chromium/src - Git at Google

 // Copyright 2019 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.chrome.browser.tasks.tab_management;

 import android.content.Context;
 import android.content.res.Resources;
 import android.graphics.Bitmap;
 import android.graphics.Canvas;
 import android.graphics.Color;
 import android.graphics.Paint;
 import android.graphics.PorterDuff;
 import android.graphics.PorterDuffXfermode;
 import android.graphics.Rect;
 import android.graphics.RectF;
 import android.graphics.drawable.Drawable;

 import org.chromium.base.ApiCompatibilityUtils;
 import org.chromium.base.Callback;
 import org.chromium.base.MathUtils;
 import org.chromium.base.task.PostTask;
 import org.chromium.chrome.browser.compositor.layouts.content.TabContentManager;
 import org.chromium.chrome.browser.profiles.Profile;
 import org.chromium.chrome.browser.tabmodel.TabModel;
 import org.chromium.chrome.browser.tabmodel.TabModelSelector;
 import org.chromium.chrome.browser.tabmodel.TabModelSelectorObserver;
 import org.chromium.chrome.browser.tasks.pseudotab.PseudoTab;
 import org.chromium.chrome.tab_ui.R;
 import org.chromium.content_public.browser.UiThreadTaskTraits;
 import org.chromium.url.GURL;

 import java.util.ArrayList;
 import java.util.List;
 import java.util.concurrent.atomic.AtomicInteger;
 import java.util.concurrent.atomic.AtomicReference;

 /**
  * A {@link TabListMediator.ThumbnailProvider} that will create a single Bitmap Thumbnail for all
  * the related tabs for the given tabs.
  */
 public class MultiThumbnailCardProvider implements TabListMediator.ThumbnailProvider {
     private final TabContentManager mTabContentManager;
     private final TabModelSelector mTabModelSelector;
     private final TabModelSelectorObserver mTabModelSelectorObserver;

     private final float mRadius;
     private final float mFaviconFrameCornerRadius;
     private final int mThumbnailWidth;
     private final int mThumbnailHeight;
     private final Paint mEmptyThumbnailPaint;
     private final Paint mThumbnailFramePaint;
     private final Paint mThumbnailBasePaint;
     private final Paint mTextPaint;
     private final Paint mFaviconBackgroundPaint;
     private final Paint mSelectedEmptyThumbnailPaint;
     private final Paint mSelectedTextPaint;
     private final int mFaviconBackgroundPaintColor;
     private final List<Rect> mFaviconRects = new ArrayList<>(4);
     private final List<RectF> mThumbnailRects = new ArrayList<>(4);
     private final List<RectF> mFaviconBackgroundRects = new ArrayList<>(4);
     private TabListFaviconProvider mTabListFaviconProvider;
     private Context mContext;

     private class MultiThumbnailFetcher {
         private final PseudoTab mInitialTab;
         private final Callback<Bitmap> mFinalCallback;
         private final boolean mForceUpdate;
         private final boolean mWriteToCache;
         private final boolean mIsTabSelected;
         private final List<PseudoTab> mTabs = new ArrayList<>(4);
         private final AtomicInteger mThumbnailsToFetch = new AtomicInteger();

         private Canvas mCanvas;
         private Bitmap mMultiThumbnailBitmap;
         private String mText;

         /**
          * Fetcher that get the thumbnail drawable depending on if the tab is selected.
          * @see TabContentManager#getTabThumbnailWithCallback
          * @param isTabSelected Whether the thumbnail is for a currently selected tab.
          */
         MultiThumbnailFetcher(PseudoTab initialTab, Callback<Bitmap> finalCallback,
                 boolean forceUpdate, boolean writeToCache, boolean isTabSelected) {
             mFinalCallback = finalCallback;
             mInitialTab = initialTab;
             mForceUpdate = forceUpdate;
             mWriteToCache = writeToCache;
             mIsTabSelected = isTabSelected;
         }

         private void initializeAndStartFetching(PseudoTab tab) {
             // Initialize mMultiThumbnailBitmap.
             int width = mThumbnailWidth;
             int height = mThumbnailHeight;
             mMultiThumbnailBitmap = Bitmap.createBitmap(width, height, Bitmap.Config.ARGB_8888);
             mCanvas = new Canvas(mMultiThumbnailBitmap);
             mCanvas.drawColor(Color.TRANSPARENT);

             // Initialize Tabs.
             List<PseudoTab> relatedTabList =
                     PseudoTab.getRelatedTabs(mContext, tab, mTabModelSelector);
             if (relatedTabList.size() <= 4) {
                 mThumbnailsToFetch.set(relatedTabList.size());

                 mTabs.add(tab);
                 relatedTabList.remove(tab);

                 for (int i = 0; i < 3; i++) {
                     mTabs.add(i < relatedTabList.size() ? relatedTabList.get(i) : null);
                 }
             } else {
                 mText = "+" + (relatedTabList.size() - 3);
                 mThumbnailsToFetch.set(3);

                 mTabs.add(tab);
                 relatedTabList.remove(tab);

                 mTabs.add(relatedTabList.get(0));
                 mTabs.add(relatedTabList.get(1));
                 mTabs.add(null);
             }

             // Fetch and draw all.
             for (int i = 0; i < 4; i++) {
                 if (mTabs.get(i) != null) {
                     final int index = i;
                     final GURL url = mTabs.get(i).getUrl();
                     final boolean isIncognito = mTabs.get(i).isIncognito();
                     // getTabThumbnailWithCallback() might call the callback up to twice,
                     // so use |lastFavicon| to avoid fetching the favicon the second time.
                     // Fetching the favicon after getting the live thumbnail would lead to
                     // visible flicker.
                     final AtomicReference<Drawable> lastFavicon = new AtomicReference<>();
                     mTabContentManager.getTabThumbnailWithCallback(
                             mTabs.get(i).getId(), thumbnail -> {
                                 drawThumbnailBitmapOnCanvasWithFrame(thumbnail, index);
                                 if (lastFavicon.get() != null) {
                                     drawFaviconThenMaybeSendBack(lastFavicon.get(), index);
                                 } else {
                                     mTabListFaviconProvider.getFaviconForUrlAsync(
                                             url, isIncognito, (Drawable favicon) -> {
                                                 lastFavicon.set(favicon);
                                                 drawFaviconThenMaybeSendBack(favicon, index);
                                             });
                                 }
                             }, mForceUpdate && i == 0, mWriteToCache && i == 0);
                 } else {
                     drawThumbnailBitmapOnCanvasWithFrame(null, i);
                     if (mText != null && i == 3) {
                         // Draw the text exactly centered on the thumbnail rect.
                         Paint textPaint = mIsTabSelected ? mSelectedTextPaint : mTextPaint;
                         mCanvas.drawText(mText,
                                 (mThumbnailRects.get(i).left + mThumbnailRects.get(i).right) / 2,
                                 (mThumbnailRects.get(i).top + mThumbnailRects.get(i).bottom) / 2
                                         - ((mTextPaint.descent() + mTextPaint.ascent()) / 2),
                                 textPaint);
                     }
                 }
             }
         }

         private void drawThumbnailBitmapOnCanvasWithFrame(Bitmap thumbnail, int index) {
             if (thumbnail == null) {
                 Paint emptyThumbnailPaint =
                         mIsTabSelected ? mSelectedEmptyThumbnailPaint : mEmptyThumbnailPaint;
                 mCanvas.drawRoundRect(
                         mThumbnailRects.get(index), mRadius, mRadius, emptyThumbnailPaint);
                 return;
             }

             // Draw the base paint first and set the base for thumbnail to draw. Setting the xfer
             // mode as SRC_OVER so the thumbnail can be drawn on top of this paint. See
             // https://crbug.com/1227619.
             mThumbnailBasePaint.setXfermode(new PorterDuffXfermode(PorterDuff.Mode.SRC_OVER));
             mCanvas.drawRoundRect(
                     mThumbnailRects.get(index), mRadius, mRadius, mThumbnailBasePaint);

             thumbnail =
                     Bitmap.createScaledBitmap(thumbnail, (int) mThumbnailRects.get(index).width(),
                             (int) mThumbnailRects.get(index).height(), true);
             mThumbnailBasePaint.setXfermode(new PorterDuffXfermode(PorterDuff.Mode.SRC_IN));
             mCanvas.drawBitmap(thumbnail,
                     new Rect(0, 0, thumbnail.getWidth(), thumbnail.getHeight()),
                     mThumbnailRects.get(index), mThumbnailBasePaint);
             thumbnail.recycle();

             mCanvas.drawRoundRect(
                     mThumbnailRects.get(index), mRadius, mRadius, mThumbnailFramePaint);
         }

         private void drawFaviconDrawableOnCanvasWithFrame(Drawable favicon, int index) {
             mCanvas.drawRoundRect(mFaviconBackgroundRects.get(index), mFaviconFrameCornerRadius,
                     mFaviconFrameCornerRadius, mFaviconBackgroundPaint);
             favicon.setBounds(mFaviconRects.get(index));
             favicon.draw(mCanvas);
         }

         private void drawFaviconThenMaybeSendBack(Drawable favicon, int index) {
             drawFaviconDrawableOnCanvasWithFrame(favicon, index);
             if (mThumbnailsToFetch.decrementAndGet() == 0) {
                 PostTask.postTask(UiThreadTaskTraits.USER_VISIBLE,
                         mFinalCallback.bind(mMultiThumbnailBitmap));
             }
         }

         private void fetch() {
             initializeAndStartFetching(mInitialTab);
         }
     }

     MultiThumbnailCardProvider(Context context, TabContentManager tabContentManager,
             TabModelSelector tabModelSelector) {
         mContext = context;
         Resources resource = context.getResources();
         float expectedThumbnailAspectRatio =
                 (float) TabUiFeatureUtilities.THUMBNAIL_ASPECT_RATIO.getValue();
         expectedThumbnailAspectRatio = MathUtils.clamp(expectedThumbnailAspectRatio, 0.5f, 2.0f);

         mThumbnailWidth = (int) resource.getDimension(R.dimen.tab_grid_thumbnail_card_default_size);
         mThumbnailHeight = (int) (mThumbnailWidth / expectedThumbnailAspectRatio);

         mTabContentManager = tabContentManager;
         mTabModelSelector = tabModelSelector;
         mRadius = resource.getDimension(R.dimen.tab_list_mini_card_radius);
         mFaviconFrameCornerRadius =
                 resource.getDimension(R.dimen.tab_grid_thumbnail_favicon_frame_corner_radius);

         mTabListFaviconProvider = new TabListFaviconProvider(context, false);

         // Initialize Paints to use.
         mEmptyThumbnailPaint = new Paint();
         mEmptyThumbnailPaint.setStyle(Paint.Style.FILL);
         mEmptyThumbnailPaint.setAntiAlias(true);
         mEmptyThumbnailPaint.setColor(
                 TabUiThemeProvider.getMiniThumbnailPlaceHolderColor(context, false, false));

         mSelectedEmptyThumbnailPaint = new Paint(mEmptyThumbnailPaint);
         mSelectedEmptyThumbnailPaint.setColor(
                 TabUiThemeProvider.getMiniThumbnailPlaceHolderColor(context, false, true));

         // Paint used to set base for thumbnails, in case mEmptyThumbnailPaint has transparency.
         mThumbnailBasePaint = new Paint(mEmptyThumbnailPaint);
         mThumbnailBasePaint.setColor(Color.BLACK);
         mThumbnailBasePaint.setXfermode(new PorterDuffXfermode(PorterDuff.Mode.SRC_IN));

         mThumbnailFramePaint = new Paint();
         mThumbnailFramePaint.setStyle(Paint.Style.STROKE);
         mThumbnailFramePaint.setStrokeWidth(
                 resource.getDimension(R.dimen.tab_list_mini_card_frame_size));
         mThumbnailFramePaint.setColor(
                 ApiCompatibilityUtils.getColor(resource, R.color.divider_line_bg_color));
         mThumbnailFramePaint.setAntiAlias(true);

         // TODO(996048): Use pre-defined styles to avoid style out of sync if any text/color styles
         // changes.
         mTextPaint = new Paint();
         mTextPaint.setTextSize(resource.getDimension(R.dimen.compositor_tab_title_text_size));
         mTextPaint.setFakeBoldText(true);
         mTextPaint.setAntiAlias(true);
         mTextPaint.setTextAlign(Paint.Align.CENTER);
         mTextPaint.setColor(TabUiThemeProvider.getTabGroupNumberTextColor(context, false, false));

         mSelectedTextPaint = new Paint(mTextPaint);
         mSelectedTextPaint.setColor(
                 TabUiThemeProvider.getTabGroupNumberTextColor(context, false, true));

         mFaviconBackgroundPaintColor =
                 ApiCompatibilityUtils.getColor(resource, R.color.favicon_background_color);
         mFaviconBackgroundPaint = new Paint();
         mFaviconBackgroundPaint.setAntiAlias(true);
         mFaviconBackgroundPaint.setColor(mFaviconBackgroundPaintColor);
         mFaviconBackgroundPaint.setStyle(Paint.Style.FILL);
         mFaviconBackgroundPaint.setShadowLayer(
                 resource.getDimension(R.dimen.tab_grid_thumbnail_favicon_background_radius), 0,
                 resource.getDimension(R.dimen.tab_grid_thumbnail_favicon_background_down_shift),
                 resource.getColor(R.color.modern_grey_800_alpha_38));

         // Initialize Rects for thumbnails.
         float thumbnailHorizontalPadding = resource.getDimension(R.dimen.tab_list_card_padding);
         float thumbnailVerticalPadding = thumbnailHorizontalPadding / expectedThumbnailAspectRatio;
         float thumbnailFaviconPaddingFromBackground =
                 resource.getDimension(R.dimen.tab_grid_thumbnail_favicon_padding_from_frame);
         float centerX = mThumbnailWidth * 0.5f;
         float centerY = mThumbnailHeight * 0.5f;
         float halfThumbnailHorizontalPadding = thumbnailHorizontalPadding / 2;
         float halfThumbnailVerticalPadding = thumbnailVerticalPadding / 2;

         mThumbnailRects.add(new RectF(thumbnailHorizontalPadding, thumbnailVerticalPadding,
                 centerX - halfThumbnailHorizontalPadding, centerY - halfThumbnailVerticalPadding));
         mThumbnailRects.add(new RectF(centerX + halfThumbnailHorizontalPadding,
                 thumbnailVerticalPadding, mThumbnailWidth - thumbnailHorizontalPadding,
                 centerY - halfThumbnailVerticalPadding));
         mThumbnailRects.add(new RectF(thumbnailHorizontalPadding,
                 centerY + halfThumbnailVerticalPadding, centerX - halfThumbnailHorizontalPadding,
                 mThumbnailHeight - thumbnailVerticalPadding));
         mThumbnailRects.add(new RectF(centerX + halfThumbnailHorizontalPadding,
                 centerY + halfThumbnailVerticalPadding,
                 mThumbnailWidth - thumbnailHorizontalPadding,
                 mThumbnailHeight - thumbnailVerticalPadding));

         // Initialize Rects for favicons and favicon frame.
         final float halfFaviconFrameSize =
                 resource.getDimension(R.dimen.tab_grid_thumbnail_favicon_frame_size) / 2f;
         for (int i = 0; i < 4; i++) {
             RectF thumbnailRect = mThumbnailRects.get(i);

             float thumbnailRectCenterX = thumbnailRect.centerX();
             float thumbnailRectCenterY = thumbnailRect.centerY();
             RectF faviconBackgroundRect = new RectF(thumbnailRectCenterX, thumbnailRectCenterY,
                     thumbnailRectCenterX, thumbnailRectCenterY);
             faviconBackgroundRect.inset(-halfFaviconFrameSize, -halfFaviconFrameSize);
             mFaviconBackgroundRects.add(faviconBackgroundRect);

             RectF faviconRectF = new RectF(faviconBackgroundRect);
             faviconRectF.inset(
                     thumbnailFaviconPaddingFromBackground, thumbnailFaviconPaddingFromBackground);
             Rect faviconRect = new Rect();
             faviconRectF.roundOut(faviconRect);
             mFaviconRects.add(faviconRect);
         }

         mTabModelSelectorObserver = new TabModelSelectorObserver() {
             @Override
             public void onTabModelSelected(TabModel newModel, TabModel oldModel) {
                 boolean isIncognito = newModel.isIncognito();
                 mEmptyThumbnailPaint.setColor(TabUiThemeProvider.getMiniThumbnailPlaceHolderColor(
                         context, isIncognito, false));
                 mTextPaint.setColor(
                         TabUiThemeProvider.getTabGroupNumberTextColor(context, isIncognito, false));
                 mThumbnailFramePaint.setColor(
                         TabUiThemeProvider.getMiniThumbnailFrameColor(context, isIncognito));
                 mFaviconBackgroundPaint.setColor(
                         TabUiThemeProvider.getFaviconBackgroundColor(context, isIncognito));

                 mSelectedEmptyThumbnailPaint.setColor(
                         TabUiThemeProvider.getMiniThumbnailPlaceHolderColor(
                                 context, isIncognito, true));
                 mSelectedTextPaint.setColor(
                         TabUiThemeProvider.getTabGroupNumberTextColor(context, isIncognito, true));
             }
         };
         mTabModelSelector.addObserver(mTabModelSelectorObserver);
     }

     public void initWithNative() {
         // TODO (https://crbug.com/1048632): Use the current profile (i.e., regular profile or
         // incognito profile) instead of always using regular profile. It works correctly now, but
         // it is not safe.
         mTabListFaviconProvider.initWithNative(Profile.getLastUsedRegularProfile());
     }

     /**
      * Destroy any member that needs clean up.
      */
     public void destroy() {
         mTabModelSelector.removeObserver(mTabModelSelectorObserver);
     }

     @Override
     public void getTabThumbnailWithCallback(
             int tabId, Callback<Bitmap> finalCallback, boolean forceUpdate, boolean writeToCache) {
         PseudoTab tab = PseudoTab.fromTabId(tabId);
         if (tab == null || PseudoTab.getRelatedTabs(mContext, tab, mTabModelSelector).size() == 1) {
             mTabContentManager.getTabThumbnailWithCallback(
                     tabId, finalCallback, forceUpdate, writeToCache);
             return;
         }
         boolean isSelected = tabId == mTabModelSelector.getCurrentTabId();
         new MultiThumbnailFetcher(tab, finalCallback, forceUpdate, writeToCache, isSelected)
                 .fetch();
     }
 }
	// Copyright 2019 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.chrome.browser.tasks.tab_management;

	import android.content.Context;
	import android.content.res.Resources;
	import android.graphics.Bitmap;
	import android.graphics.Canvas;
	import android.graphics.Color;
	import android.graphics.Paint;
	import android.graphics.PorterDuff;
	import android.graphics.PorterDuffXfermode;
	import android.graphics.Rect;
	import android.graphics.RectF;
	import android.graphics.drawable.Drawable;

	import org.chromium.base.ApiCompatibilityUtils;
	import org.chromium.base.Callback;
	import org.chromium.base.MathUtils;
	import org.chromium.base.task.PostTask;
	import org.chromium.chrome.browser.compositor.layouts.content.TabContentManager;
	import org.chromium.chrome.browser.profiles.Profile;
	import org.chromium.chrome.browser.tabmodel.TabModel;
	import org.chromium.chrome.browser.tabmodel.TabModelSelector;
	import org.chromium.chrome.browser.tabmodel.TabModelSelectorObserver;
	import org.chromium.chrome.browser.tasks.pseudotab.PseudoTab;
	import org.chromium.chrome.tab_ui.R;
	import org.chromium.content_public.browser.UiThreadTaskTraits;
	import org.chromium.url.GURL;

	import java.util.ArrayList;
	import java.util.List;
	import java.util.concurrent.atomic.AtomicInteger;
	import java.util.concurrent.atomic.AtomicReference;

	/**
	* A {@link TabListMediator.ThumbnailProvider} that will create a single Bitmap Thumbnail for all
	* the related tabs for the given tabs.
	*/
	public class MultiThumbnailCardProvider implements TabListMediator.ThumbnailProvider {
	private final TabContentManager mTabContentManager;
	private final TabModelSelector mTabModelSelector;
	private final TabModelSelectorObserver mTabModelSelectorObserver;

	private final float mRadius;
	private final float mFaviconFrameCornerRadius;
	private final int mThumbnailWidth;
	private final int mThumbnailHeight;
	private final Paint mEmptyThumbnailPaint;
	private final Paint mThumbnailFramePaint;
	private final Paint mThumbnailBasePaint;
	private final Paint mTextPaint;
	private final Paint mFaviconBackgroundPaint;
	private final Paint mSelectedEmptyThumbnailPaint;
	private final Paint mSelectedTextPaint;
	private final int mFaviconBackgroundPaintColor;
	private final List<Rect> mFaviconRects = new ArrayList<>(4);
	private final List<RectF> mThumbnailRects = new ArrayList<>(4);
	private final List<RectF> mFaviconBackgroundRects = new ArrayList<>(4);
	private TabListFaviconProvider mTabListFaviconProvider;
	private Context mContext;

	private class MultiThumbnailFetcher {
	private final PseudoTab mInitialTab;
	private final Callback<Bitmap> mFinalCallback;
	private final boolean mForceUpdate;
	private final boolean mWriteToCache;
	private final boolean mIsTabSelected;
	private final List<PseudoTab> mTabs = new ArrayList<>(4);
	private final AtomicInteger mThumbnailsToFetch = new AtomicInteger();

	private Canvas mCanvas;
	private Bitmap mMultiThumbnailBitmap;
	private String mText;

	/**
	* Fetcher that get the thumbnail drawable depending on if the tab is selected.
	* @see TabContentManager#getTabThumbnailWithCallback
	* @param isTabSelected Whether the thumbnail is for a currently selected tab.
	*/
	MultiThumbnailFetcher(PseudoTab initialTab, Callback<Bitmap> finalCallback,
	boolean forceUpdate, boolean writeToCache, boolean isTabSelected) {
	mFinalCallback = finalCallback;
	mInitialTab = initialTab;
	mForceUpdate = forceUpdate;
	mWriteToCache = writeToCache;
	mIsTabSelected = isTabSelected;
	}

	private void initializeAndStartFetching(PseudoTab tab) {
	// Initialize mMultiThumbnailBitmap.
	int width = mThumbnailWidth;
	int height = mThumbnailHeight;
	mMultiThumbnailBitmap = Bitmap.createBitmap(width, height, Bitmap.Config.ARGB_8888);
	mCanvas = new Canvas(mMultiThumbnailBitmap);
	mCanvas.drawColor(Color.TRANSPARENT);

	// Initialize Tabs.
	List<PseudoTab> relatedTabList =
	PseudoTab.getRelatedTabs(mContext, tab, mTabModelSelector);
	if (relatedTabList.size() <= 4) {
	mThumbnailsToFetch.set(relatedTabList.size());

	mTabs.add(tab);
	relatedTabList.remove(tab);

	for (int i = 0; i < 3; i++) {
	mTabs.add(i < relatedTabList.size() ? relatedTabList.get(i) : null);
	}
	} else {
	mText = "+" + (relatedTabList.size() - 3);
	mThumbnailsToFetch.set(3);

	mTabs.add(tab);
	relatedTabList.remove(tab);

	mTabs.add(relatedTabList.get(0));
	mTabs.add(relatedTabList.get(1));
	mTabs.add(null);
	}

	// Fetch and draw all.
	for (int i = 0; i < 4; i++) {
	if (mTabs.get(i) != null) {
	final int index = i;
	final GURL url = mTabs.get(i).getUrl();
	final boolean isIncognito = mTabs.get(i).isIncognito();
	// getTabThumbnailWithCallback() might call the callback up to twice,
	// so use \|lastFavicon\| to avoid fetching the favicon the second time.
	// Fetching the favicon after getting the live thumbnail would lead to
	// visible flicker.
	final AtomicReference<Drawable> lastFavicon = new AtomicReference<>();
	mTabContentManager.getTabThumbnailWithCallback(
	mTabs.get(i).getId(), thumbnail -> {
	drawThumbnailBitmapOnCanvasWithFrame(thumbnail, index);
	if (lastFavicon.get() != null) {
	drawFaviconThenMaybeSendBack(lastFavicon.get(), index);
	} else {
	mTabListFaviconProvider.getFaviconForUrlAsync(
	url, isIncognito, (Drawable favicon) -> {
	lastFavicon.set(favicon);
	drawFaviconThenMaybeSendBack(favicon, index);
	});
	}
	}, mForceUpdate && i == 0, mWriteToCache && i == 0);
	} else {
	drawThumbnailBitmapOnCanvasWithFrame(null, i);
	if (mText != null && i == 3) {
	// Draw the text exactly centered on the thumbnail rect.
	Paint textPaint = mIsTabSelected ? mSelectedTextPaint : mTextPaint;
	mCanvas.drawText(mText,
	(mThumbnailRects.get(i).left + mThumbnailRects.get(i).right) / 2,
	(mThumbnailRects.get(i).top + mThumbnailRects.get(i).bottom) / 2
	- ((mTextPaint.descent() + mTextPaint.ascent()) / 2),
	textPaint);
	}
	}
	}
	}

	private void drawThumbnailBitmapOnCanvasWithFrame(Bitmap thumbnail, int index) {
	if (thumbnail == null) {
	Paint emptyThumbnailPaint =
	mIsTabSelected ? mSelectedEmptyThumbnailPaint : mEmptyThumbnailPaint;
	mCanvas.drawRoundRect(
	mThumbnailRects.get(index), mRadius, mRadius, emptyThumbnailPaint);
	return;
	}

	// Draw the base paint first and set the base for thumbnail to draw. Setting the xfer
	// mode as SRC_OVER so the thumbnail can be drawn on top of this paint. See
	// https://crbug.com/1227619.
	mThumbnailBasePaint.setXfermode(new PorterDuffXfermode(PorterDuff.Mode.SRC_OVER));
	mCanvas.drawRoundRect(
	mThumbnailRects.get(index), mRadius, mRadius, mThumbnailBasePaint);

	thumbnail =
	Bitmap.createScaledBitmap(thumbnail, (int) mThumbnailRects.get(index).width(),
	(int) mThumbnailRects.get(index).height(), true);
	mThumbnailBasePaint.setXfermode(new PorterDuffXfermode(PorterDuff.Mode.SRC_IN));
	mCanvas.drawBitmap(thumbnail,
	new Rect(0, 0, thumbnail.getWidth(), thumbnail.getHeight()),
	mThumbnailRects.get(index), mThumbnailBasePaint);
	thumbnail.recycle();

	mCanvas.drawRoundRect(
	mThumbnailRects.get(index), mRadius, mRadius, mThumbnailFramePaint);
	}

	private void drawFaviconDrawableOnCanvasWithFrame(Drawable favicon, int index) {
	mCanvas.drawRoundRect(mFaviconBackgroundRects.get(index), mFaviconFrameCornerRadius,
	mFaviconFrameCornerRadius, mFaviconBackgroundPaint);
	favicon.setBounds(mFaviconRects.get(index));
	favicon.draw(mCanvas);
	}

	private void drawFaviconThenMaybeSendBack(Drawable favicon, int index) {
	drawFaviconDrawableOnCanvasWithFrame(favicon, index);
	if (mThumbnailsToFetch.decrementAndGet() == 0) {
	PostTask.postTask(UiThreadTaskTraits.USER_VISIBLE,
	mFinalCallback.bind(mMultiThumbnailBitmap));
	}
	}

	private void fetch() {
	initializeAndStartFetching(mInitialTab);
	}
	}

	MultiThumbnailCardProvider(Context context, TabContentManager tabContentManager,
	TabModelSelector tabModelSelector) {
	mContext = context;
	Resources resource = context.getResources();
	float expectedThumbnailAspectRatio =
	(float) TabUiFeatureUtilities.THUMBNAIL_ASPECT_RATIO.getValue();
	expectedThumbnailAspectRatio = MathUtils.clamp(expectedThumbnailAspectRatio, 0.5f, 2.0f);

	mThumbnailWidth = (int) resource.getDimension(R.dimen.tab_grid_thumbnail_card_default_size);
	mThumbnailHeight = (int) (mThumbnailWidth / expectedThumbnailAspectRatio);

	mTabContentManager = tabContentManager;
	mTabModelSelector = tabModelSelector;
	mRadius = resource.getDimension(R.dimen.tab_list_mini_card_radius);
	mFaviconFrameCornerRadius =
	resource.getDimension(R.dimen.tab_grid_thumbnail_favicon_frame_corner_radius);

	mTabListFaviconProvider = new TabListFaviconProvider(context, false);

	// Initialize Paints to use.
	mEmptyThumbnailPaint = new Paint();
	mEmptyThumbnailPaint.setStyle(Paint.Style.FILL);
	mEmptyThumbnailPaint.setAntiAlias(true);
	mEmptyThumbnailPaint.setColor(
	TabUiThemeProvider.getMiniThumbnailPlaceHolderColor(context, false, false));

	mSelectedEmptyThumbnailPaint = new Paint(mEmptyThumbnailPaint);
	mSelectedEmptyThumbnailPaint.setColor(
	TabUiThemeProvider.getMiniThumbnailPlaceHolderColor(context, false, true));

	// Paint used to set base for thumbnails, in case mEmptyThumbnailPaint has transparency.
	mThumbnailBasePaint = new Paint(mEmptyThumbnailPaint);
	mThumbnailBasePaint.setColor(Color.BLACK);
	mThumbnailBasePaint.setXfermode(new PorterDuffXfermode(PorterDuff.Mode.SRC_IN));

	mThumbnailFramePaint = new Paint();
	mThumbnailFramePaint.setStyle(Paint.Style.STROKE);
	mThumbnailFramePaint.setStrokeWidth(
	resource.getDimension(R.dimen.tab_list_mini_card_frame_size));
	mThumbnailFramePaint.setColor(
	ApiCompatibilityUtils.getColor(resource, R.color.divider_line_bg_color));
	mThumbnailFramePaint.setAntiAlias(true);

	// TODO(996048): Use pre-defined styles to avoid style out of sync if any text/color styles
	// changes.
	mTextPaint = new Paint();
	mTextPaint.setTextSize(resource.getDimension(R.dimen.compositor_tab_title_text_size));
	mTextPaint.setFakeBoldText(true);
	mTextPaint.setAntiAlias(true);
	mTextPaint.setTextAlign(Paint.Align.CENTER);
	mTextPaint.setColor(TabUiThemeProvider.getTabGroupNumberTextColor(context, false, false));

	mSelectedTextPaint = new Paint(mTextPaint);
	mSelectedTextPaint.setColor(
	TabUiThemeProvider.getTabGroupNumberTextColor(context, false, true));

	mFaviconBackgroundPaintColor =
	ApiCompatibilityUtils.getColor(resource, R.color.favicon_background_color);
	mFaviconBackgroundPaint = new Paint();
	mFaviconBackgroundPaint.setAntiAlias(true);
	mFaviconBackgroundPaint.setColor(mFaviconBackgroundPaintColor);
	mFaviconBackgroundPaint.setStyle(Paint.Style.FILL);
	mFaviconBackgroundPaint.setShadowLayer(
	resource.getDimension(R.dimen.tab_grid_thumbnail_favicon_background_radius), 0,
	resource.getDimension(R.dimen.tab_grid_thumbnail_favicon_background_down_shift),
	resource.getColor(R.color.modern_grey_800_alpha_38));

	// Initialize Rects for thumbnails.
	float thumbnailHorizontalPadding = resource.getDimension(R.dimen.tab_list_card_padding);
	float thumbnailVerticalPadding = thumbnailHorizontalPadding / expectedThumbnailAspectRatio;
	float thumbnailFaviconPaddingFromBackground =
	resource.getDimension(R.dimen.tab_grid_thumbnail_favicon_padding_from_frame);
	float centerX = mThumbnailWidth * 0.5f;
	float centerY = mThumbnailHeight * 0.5f;
	float halfThumbnailHorizontalPadding = thumbnailHorizontalPadding / 2;
	float halfThumbnailVerticalPadding = thumbnailVerticalPadding / 2;

	mThumbnailRects.add(new RectF(thumbnailHorizontalPadding, thumbnailVerticalPadding,
	centerX - halfThumbnailHorizontalPadding, centerY - halfThumbnailVerticalPadding));
	mThumbnailRects.add(new RectF(centerX + halfThumbnailHorizontalPadding,
	thumbnailVerticalPadding, mThumbnailWidth - thumbnailHorizontalPadding,
	centerY - halfThumbnailVerticalPadding));
	mThumbnailRects.add(new RectF(thumbnailHorizontalPadding,
	centerY + halfThumbnailVerticalPadding, centerX - halfThumbnailHorizontalPadding,
	mThumbnailHeight - thumbnailVerticalPadding));
	mThumbnailRects.add(new RectF(centerX + halfThumbnailHorizontalPadding,
	centerY + halfThumbnailVerticalPadding,
	mThumbnailWidth - thumbnailHorizontalPadding,
	mThumbnailHeight - thumbnailVerticalPadding));

	// Initialize Rects for favicons and favicon frame.
	final float halfFaviconFrameSize =
	resource.getDimension(R.dimen.tab_grid_thumbnail_favicon_frame_size) / 2f;
	for (int i = 0; i < 4; i++) {
	RectF thumbnailRect = mThumbnailRects.get(i);

	float thumbnailRectCenterX = thumbnailRect.centerX();
	float thumbnailRectCenterY = thumbnailRect.centerY();
	RectF faviconBackgroundRect = new RectF(thumbnailRectCenterX, thumbnailRectCenterY,
	thumbnailRectCenterX, thumbnailRectCenterY);
	faviconBackgroundRect.inset(-halfFaviconFrameSize, -halfFaviconFrameSize);
	mFaviconBackgroundRects.add(faviconBackgroundRect);

	RectF faviconRectF = new RectF(faviconBackgroundRect);
	faviconRectF.inset(
	thumbnailFaviconPaddingFromBackground, thumbnailFaviconPaddingFromBackground);
	Rect faviconRect = new Rect();
	faviconRectF.roundOut(faviconRect);
	mFaviconRects.add(faviconRect);
	}

	mTabModelSelectorObserver = new TabModelSelectorObserver() {
	@Override
	public void onTabModelSelected(TabModel newModel, TabModel oldModel) {
	boolean isIncognito = newModel.isIncognito();
	mEmptyThumbnailPaint.setColor(TabUiThemeProvider.getMiniThumbnailPlaceHolderColor(
	context, isIncognito, false));
	mTextPaint.setColor(
	TabUiThemeProvider.getTabGroupNumberTextColor(context, isIncognito, false));
	mThumbnailFramePaint.setColor(
	TabUiThemeProvider.getMiniThumbnailFrameColor(context, isIncognito));
	mFaviconBackgroundPaint.setColor(
	TabUiThemeProvider.getFaviconBackgroundColor(context, isIncognito));

	mSelectedEmptyThumbnailPaint.setColor(
	TabUiThemeProvider.getMiniThumbnailPlaceHolderColor(
	context, isIncognito, true));
	mSelectedTextPaint.setColor(
	TabUiThemeProvider.getTabGroupNumberTextColor(context, isIncognito, true));
	}
	};
	mTabModelSelector.addObserver(mTabModelSelectorObserver);
	}

	public void initWithNative() {
	// TODO (https://crbug.com/1048632): Use the current profile (i.e., regular profile or
	// incognito profile) instead of always using regular profile. It works correctly now, but
	// it is not safe.
	mTabListFaviconProvider.initWithNative(Profile.getLastUsedRegularProfile());
	}

	/**
	* Destroy any member that needs clean up.
	*/
	public void destroy() {
	mTabModelSelector.removeObserver(mTabModelSelectorObserver);
	}

	@Override
	public void getTabThumbnailWithCallback(
	int tabId, Callback<Bitmap> finalCallback, boolean forceUpdate, boolean writeToCache) {
	PseudoTab tab = PseudoTab.fromTabId(tabId);
	if (tab == null \|\| PseudoTab.getRelatedTabs(mContext, tab, mTabModelSelector).size() == 1) {
	mTabContentManager.getTabThumbnailWithCallback(
	tabId, finalCallback, forceUpdate, writeToCache);
	return;
	}
	boolean isSelected = tabId == mTabModelSelector.getCurrentTabId();
	new MultiThumbnailFetcher(tab, finalCallback, forceUpdate, writeToCache, isSelected)
	.fetch();
	}
	}