java/src/com/android/intentresolver/grid/ChooserGridAdapter.java - platform/packages/modules/IntentResolver - Gitiles

 /*
  * Copyright (C) 2008 The Android Open Source Project
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
  *
  *      http://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */

 package com.android.intentresolver.grid;

 import android.animation.AnimatorSet;
 import android.animation.ObjectAnimator;
 import android.animation.ValueAnimator;
 import android.app.ActivityManager;
 import android.content.Context;
 import android.database.DataSetObserver;
 import android.view.LayoutInflater;
 import android.view.View;
 import android.view.View.MeasureSpec;
 import android.view.View.OnClickListener;
 import android.view.ViewGroup;
 import android.view.ViewGroup.LayoutParams;
 import android.view.animation.DecelerateInterpolator;
 import android.widget.Space;
 import android.widget.TextView;

 import androidx.recyclerview.widget.RecyclerView;

 import com.android.intentresolver.ChooserListAdapter;
 import com.android.intentresolver.R;
 import com.android.intentresolver.ResolverListAdapter.ViewHolder;
 import com.android.internal.annotations.VisibleForTesting;

 import com.google.android.collect.Lists;

 /**
  * Adapter for all types of items and targets in ShareSheet.
  * Note that ranked sections like Direct Share - while appearing grid-like - are handled on the
  * row level by this adapter but not on the item level. Individual targets within the row are
  * handled by {@link ChooserListAdapter}
  */
 @VisibleForTesting
 public final class ChooserGridAdapter extends RecyclerView.Adapter<RecyclerView.ViewHolder> {

     /**
      * The transition time between placeholders for direct share to a message
      * indicating that none are available.
      */
     public static final int NO_DIRECT_SHARE_ANIM_IN_MILLIS = 200;

     /**
      * Injectable interface for any considerations that should be delegated to other components
      * in the {@link ChooserActivity}.
      * TODO: determine whether any of these methods return parameters that can safely be
      * precomputed; whether any should be converted to `ChooserGridAdapter` setters to be
      * invoked by external callbacks; and whether any reflect requirements that should be moved
      * out of `ChooserGridAdapter` altogether.
      */
     public interface ChooserActivityDelegate {
         /** @return whether we're showing a tabbed (multi-profile) UI. */
         boolean shouldShowTabs();

         /**
          * @return a content preview {@link View} that's appropriate for the caller's share
          * content, constructed for display in the provided {@code parent} group.
          */
         View buildContentPreview(ViewGroup parent);

         /** Notify the client that the item with the selected {@code itemIndex} was selected. */
         void onTargetSelected(int itemIndex);

         /**
          * Notify the client that the item with the selected {@code itemIndex} was
          * long-pressed.
          */
         void onTargetLongPressed(int itemIndex);

         /**
          * Notify the client that the provided {@code View} should be configured as the new
          * "profile view" button. Callers should attach their own click listeners to implement
          * behaviors on this view.
          */
         void updateProfileViewButton(View newButtonFromProfileRow);

         /**
          * @return the number of "valid" targets in the active list adapter.
          * TODO: define "valid."
          */
         int getValidTargetCount();

         /**
          * Request that the client update our {@code directShareGroup} to match their desired
          * state for the "expansion" UI.
          */
         void updateDirectShareExpansion(DirectShareViewHolder directShareGroup);

         /**
          * Request that the client handle a scroll event that should be taken as expanding the
          * provided {@code directShareGroup}. Note that this currently never happens due to a
          * hard-coded condition in {@link #canExpandDirectShare()}.
          */
         void handleScrollToExpandDirectShare(
                 DirectShareViewHolder directShareGroup, int y, int oldy);
     }

     private static final int VIEW_TYPE_DIRECT_SHARE = 0;
     private static final int VIEW_TYPE_NORMAL = 1;
     private static final int VIEW_TYPE_CONTENT_PREVIEW = 2;
     private static final int VIEW_TYPE_PROFILE = 3;
     private static final int VIEW_TYPE_AZ_LABEL = 4;
     private static final int VIEW_TYPE_CALLER_AND_RANK = 5;
     private static final int VIEW_TYPE_FOOTER = 6;

     private static final int NUM_EXPANSIONS_TO_HIDE_AZ_LABEL = 20;

     private final ChooserActivityDelegate mChooserActivityDelegate;
     private final ChooserListAdapter mChooserListAdapter;
     private final LayoutInflater mLayoutInflater;

     private final int mMaxTargetsPerRow;
     private final boolean mShouldShowContentPreview;
     private final int mChooserWidthPixels;
     private final int mChooserRowTextOptionTranslatePixelSize;
     private final boolean mShowAzLabelIfPoss;

     private DirectShareViewHolder mDirectShareViewHolder;
     private int mChooserTargetWidth = 0;

     private int mFooterHeight = 0;

     public ChooserGridAdapter(
             Context context,
             ChooserActivityDelegate chooserActivityDelegate,
             ChooserListAdapter wrappedAdapter,
             boolean shouldShowContentPreview,
             int maxTargetsPerRow,
             int numSheetExpansions) {
         super();

         mChooserActivityDelegate = chooserActivityDelegate;

         mChooserListAdapter = wrappedAdapter;
         mLayoutInflater = LayoutInflater.from(context);

         mShouldShowContentPreview = shouldShowContentPreview;
         mMaxTargetsPerRow = maxTargetsPerRow;

         mChooserWidthPixels = context.getResources().getDimensionPixelSize(R.dimen.chooser_width);
         mChooserRowTextOptionTranslatePixelSize = context.getResources().getDimensionPixelSize(
                 R.dimen.chooser_row_text_option_translate);

         mShowAzLabelIfPoss = numSheetExpansions < NUM_EXPANSIONS_TO_HIDE_AZ_LABEL;

         wrappedAdapter.registerDataSetObserver(new DataSetObserver() {
             @Override
             public void onChanged() {
                 super.onChanged();
                 notifyDataSetChanged();
             }

             @Override
             public void onInvalidated() {
                 super.onInvalidated();
                 notifyDataSetChanged();
             }
         });
     }

     public void setFooterHeight(int height) {
         mFooterHeight = height;
     }

     /**
      * Calculate the chooser target width to maximize space per item
      *
      * @param width The new row width to use for recalculation
      * @return true if the view width has changed
      */
     public boolean calculateChooserTargetWidth(int width) {
         if (width == 0) {
             return false;
         }

         // Limit width to the maximum width of the chooser activity
         int maxWidth = mChooserWidthPixels;
         width = Math.min(maxWidth, width);

         int newWidth = width / mMaxTargetsPerRow;
         if (newWidth != mChooserTargetWidth) {
             mChooserTargetWidth = newWidth;
             return true;
         }

         return false;
     }

     public int getRowCount() {
         return (int) (
                 getSystemRowCount()
                         + getProfileRowCount()
                         + getServiceTargetRowCount()
                         + getCallerAndRankedTargetRowCount()
                         + getAzLabelRowCount()
                         + Math.ceil(
                         (float) mChooserListAdapter.getAlphaTargetCount()
                                 / mMaxTargetsPerRow)
             );
     }

     /**
      * Whether the "system" row of targets is displayed.
      * This area includes the content preview (if present) and action row.
      */
     public int getSystemRowCount() {
         // For the tabbed case we show the sticky content preview above the tabs,
         // please refer to shouldShowStickyContentPreview
         if (mChooserActivityDelegate.shouldShowTabs()) {
             return 0;
         }

         if (!mShouldShowContentPreview) {
             return 0;
         }

         if (mChooserListAdapter == null || mChooserListAdapter.getCount() == 0) {
             return 0;
         }

         return 1;
     }

     public int getProfileRowCount() {
         if (mChooserActivityDelegate.shouldShowTabs()) {
             return 0;
         }
         return mChooserListAdapter.getOtherProfile() == null ? 0 : 1;
     }

     public int getFooterRowCount() {
         return 1;
     }

     public int getCallerAndRankedTargetRowCount() {
         return (int) Math.ceil(
                 ((float) mChooserListAdapter.getCallerTargetCount()
                         + mChooserListAdapter.getRankedTargetCount()) / mMaxTargetsPerRow);
     }

     // There can be at most one row in the listview, that is internally
     // a ViewGroup with 2 rows
     public int getServiceTargetRowCount() {
         if (mShouldShowContentPreview && !ActivityManager.isLowRamDeviceStatic()) {
             return 1;
         }
         return 0;
     }

     public int getAzLabelRowCount() {
         // Only show a label if the a-z list is showing
         return (mShowAzLabelIfPoss && mChooserListAdapter.getAlphaTargetCount() > 0) ? 1 : 0;
     }

     @Override
     public int getItemCount() {
         return (int) (
                 getSystemRowCount()
                         + getProfileRowCount()
                         + getServiceTargetRowCount()
                         + getCallerAndRankedTargetRowCount()
                         + getAzLabelRowCount()
                         + mChooserListAdapter.getAlphaTargetCount()
                         + getFooterRowCount()
             );
     }

     @Override
     public RecyclerView.ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
         switch (viewType) {
             case VIEW_TYPE_CONTENT_PREVIEW:
                 return new ItemViewHolder(
                         mChooserActivityDelegate.buildContentPreview(parent),
                         viewType,
                         null,
                         null);
             case VIEW_TYPE_PROFILE:
                 return new ItemViewHolder(
                         createProfileView(parent),
                         viewType,
                         null,
                         null);
             case VIEW_TYPE_AZ_LABEL:
                 return new ItemViewHolder(
                         createAzLabelView(parent),
                         viewType,
                         null,
                         null);
             case VIEW_TYPE_NORMAL:
                 return new ItemViewHolder(
                         mChooserListAdapter.createView(parent),
                         viewType,
                         mChooserActivityDelegate::onTargetSelected,
                         mChooserActivityDelegate::onTargetLongPressed);
             case VIEW_TYPE_DIRECT_SHARE:
             case VIEW_TYPE_CALLER_AND_RANK:
                 return createItemGroupViewHolder(viewType, parent);
             case VIEW_TYPE_FOOTER:
                 Space sp = new Space(parent.getContext());
                 sp.setLayoutParams(new RecyclerView.LayoutParams(
                         LayoutParams.MATCH_PARENT, mFooterHeight));
                 return new FooterViewHolder(sp, viewType);
             default:
                 // Since we catch all possible viewTypes above, no chance this is being called.
                 return null;
         }
     }

     @Override
     public void onBindViewHolder(RecyclerView.ViewHolder holder, int position) {
         int viewType = ((ViewHolderBase) holder).getViewType();
         switch (viewType) {
             case VIEW_TYPE_DIRECT_SHARE:
             case VIEW_TYPE_CALLER_AND_RANK:
                 bindItemGroupViewHolder(position, (ItemGroupViewHolder) holder);
                 break;
             case VIEW_TYPE_NORMAL:
                 bindItemViewHolder(position, (ItemViewHolder) holder);
                 break;
             default:
         }
     }

     @Override
     public int getItemViewType(int position) {
         int count;

         int countSum = (count = getSystemRowCount());
         if (count > 0 && position < countSum) return VIEW_TYPE_CONTENT_PREVIEW;

         countSum += (count = getProfileRowCount());
         if (count > 0 && position < countSum) return VIEW_TYPE_PROFILE;

         countSum += (count = getServiceTargetRowCount());
         if (count > 0 && position < countSum) return VIEW_TYPE_DIRECT_SHARE;

         countSum += (count = getCallerAndRankedTargetRowCount());
         if (count > 0 && position < countSum) return VIEW_TYPE_CALLER_AND_RANK;

         countSum += (count = getAzLabelRowCount());
         if (count > 0 && position < countSum) return VIEW_TYPE_AZ_LABEL;

         if (position == getItemCount() - 1) return VIEW_TYPE_FOOTER;

         return VIEW_TYPE_NORMAL;
     }

     public int getTargetType(int position) {
         return mChooserListAdapter.getPositionTargetType(getListPosition(position));
     }

     private View createProfileView(ViewGroup parent) {
         View profileRow = mLayoutInflater.inflate(R.layout.chooser_profile_row, parent, false);
         mChooserActivityDelegate.updateProfileViewButton(profileRow);
         return profileRow;
     }

     private View createAzLabelView(ViewGroup parent) {
         return mLayoutInflater.inflate(R.layout.chooser_az_label_row, parent, false);
     }

     private ItemGroupViewHolder loadViewsIntoGroup(ItemGroupViewHolder holder) {
         final int spec = MeasureSpec.makeMeasureSpec(0, MeasureSpec.UNSPECIFIED);
         final int exactSpec = MeasureSpec.makeMeasureSpec(mChooserTargetWidth, MeasureSpec.EXACTLY);
         int columnCount = holder.getColumnCount();

         final boolean isDirectShare = holder instanceof DirectShareViewHolder;

         for (int i = 0; i < columnCount; i++) {
             final View v = mChooserListAdapter.createView(holder.getRowByIndex(i));
             final int column = i;
             v.setOnClickListener(new OnClickListener() {
                 @Override
                 public void onClick(View v) {
                     mChooserActivityDelegate.onTargetSelected(holder.getItemIndex(column));
                 }
             });

             // Show menu for both direct share and app share targets after long click.
             v.setOnLongClickListener(v1 -> {
                 mChooserActivityDelegate.onTargetLongPressed(holder.getItemIndex(column));
                 return true;
             });

             holder.addView(i, v);

             // Force Direct Share to be 2 lines and auto-wrap to second line via hoz scroll =
             // false. TextView#setHorizontallyScrolling must be reset after #setLines. Must be
             // done before measuring.
             if (isDirectShare) {
                 final ViewHolder vh = (ViewHolder) v.getTag();
                 vh.text.setLines(2);
                 vh.text.setHorizontallyScrolling(false);
                 vh.text2.setVisibility(View.GONE);
             }

             // Force height to be a given so we don't have visual disruption during scaling.
             v.measure(exactSpec, spec);
             setViewBounds(v, v.getMeasuredWidth(), v.getMeasuredHeight());
         }

         final ViewGroup viewGroup = holder.getViewGroup();

         // Pre-measure and fix height so we can scale later.
         holder.measure();
         setViewBounds(viewGroup, LayoutParams.MATCH_PARENT, holder.getMeasuredRowHeight());

         if (isDirectShare) {
             DirectShareViewHolder dsvh = (DirectShareViewHolder) holder;
             setViewBounds(dsvh.getRow(0), LayoutParams.MATCH_PARENT, dsvh.getMinRowHeight());
             setViewBounds(dsvh.getRow(1), LayoutParams.MATCH_PARENT, dsvh.getMinRowHeight());
         }

         viewGroup.setTag(holder);
         return holder;
     }

     private void setViewBounds(View view, int widthPx, int heightPx) {
         LayoutParams lp = view.getLayoutParams();
         if (lp == null) {
             lp = new LayoutParams(widthPx, heightPx);
             view.setLayoutParams(lp);
         } else {
             lp.height = heightPx;
             lp.width = widthPx;
         }
     }

     ItemGroupViewHolder createItemGroupViewHolder(int viewType, ViewGroup parent) {
         if (viewType == VIEW_TYPE_DIRECT_SHARE) {
             ViewGroup parentGroup = (ViewGroup) mLayoutInflater.inflate(
                     R.layout.chooser_row_direct_share, parent, false);
             ViewGroup row1 = (ViewGroup) mLayoutInflater.inflate(
                     R.layout.chooser_row, parentGroup, false);
             ViewGroup row2 = (ViewGroup) mLayoutInflater.inflate(
                     R.layout.chooser_row, parentGroup, false);
             parentGroup.addView(row1);
             parentGroup.addView(row2);

             mDirectShareViewHolder = new DirectShareViewHolder(parentGroup,
                     Lists.newArrayList(row1, row2), mMaxTargetsPerRow, viewType,
                     mChooserActivityDelegate::getValidTargetCount);
             loadViewsIntoGroup(mDirectShareViewHolder);

             return mDirectShareViewHolder;
         } else {
             ViewGroup row = (ViewGroup) mLayoutInflater.inflate(
                     R.layout.chooser_row, parent, false);
             ItemGroupViewHolder holder =
                     new SingleRowViewHolder(row, mMaxTargetsPerRow, viewType);
             loadViewsIntoGroup(holder);

             return holder;
         }
     }

     /**
      * Need to merge CALLER + ranked STANDARD into a single row and prevent a separator from
      * showing on top of the AZ list if the AZ label is visible. All other types are placed into
      * their own row as determined by their target type, and dividers are added in the list to
      * separate each type.
      */
     int getRowType(int rowPosition) {
         // Merge caller and ranked standard into a single row
         int positionType = mChooserListAdapter.getPositionTargetType(rowPosition);
         if (positionType == ChooserListAdapter.TARGET_CALLER) {
             return ChooserListAdapter.TARGET_STANDARD;
         }

         // If an A-Z label is shown, prevent a separator from appearing by making the A-Z
         // row type the same as the suggestion row type
         if (getAzLabelRowCount() > 0 && positionType == ChooserListAdapter.TARGET_STANDARD_AZ) {
             return ChooserListAdapter.TARGET_STANDARD;
         }

         return positionType;
     }

     void bindItemViewHolder(int position, ItemViewHolder holder) {
         View v = holder.itemView;
         int listPosition = getListPosition(position);
         holder.setListPosition(listPosition);
         mChooserListAdapter.bindView(listPosition, v);
     }

     void bindItemGroupViewHolder(int position, ItemGroupViewHolder holder) {
         final ViewGroup viewGroup = (ViewGroup) holder.itemView;
         int start = getListPosition(position);
         int startType = getRowType(start);

         int columnCount = holder.getColumnCount();
         int end = start + columnCount - 1;
         while (getRowType(end) != startType && end >= start) {
             end--;
         }

         if (end == start && mChooserListAdapter.getItem(start).isEmptyTargetInfo()) {
             final TextView textView = viewGroup.findViewById(
                     com.android.internal.R.id.chooser_row_text_option);

             if (textView.getVisibility() != View.VISIBLE) {
                 textView.setAlpha(0.0f);
                 textView.setVisibility(View.VISIBLE);
                 textView.setText(R.string.chooser_no_direct_share_targets);

                 ValueAnimator fadeAnim = ObjectAnimator.ofFloat(textView, "alpha", 0.0f, 1.0f);
                 fadeAnim.setInterpolator(new DecelerateInterpolator(1.0f));

                 textView.setTranslationY(mChooserRowTextOptionTranslatePixelSize);
                 ValueAnimator translateAnim =
                         ObjectAnimator.ofFloat(textView, "translationY", 0.0f);
                 translateAnim.setInterpolator(new DecelerateInterpolator(1.0f));

                 AnimatorSet animSet = new AnimatorSet();
                 animSet.setDuration(NO_DIRECT_SHARE_ANIM_IN_MILLIS);
                 animSet.setStartDelay(NO_DIRECT_SHARE_ANIM_IN_MILLIS);
                 animSet.playTogether(fadeAnim, translateAnim);
                 animSet.start();
             }
         }

         for (int i = 0; i < columnCount; i++) {
             final View v = holder.getView(i);

             if (start + i <= end) {
                 holder.setViewVisibility(i, View.VISIBLE);
                 holder.setItemIndex(i, start + i);
                 mChooserListAdapter.bindView(holder.getItemIndex(i), v);
             } else {
                 holder.setViewVisibility(i, View.INVISIBLE);
             }
         }
     }

     int getListPosition(int position) {
         position -= getSystemRowCount() + getProfileRowCount();

         final int serviceCount = mChooserListAdapter.getServiceTargetCount();
         final int serviceRows = (int) Math.ceil((float) serviceCount / mMaxTargetsPerRow);
         if (position < serviceRows) {
             return position * mMaxTargetsPerRow;
         }

         position -= serviceRows;

         final int callerAndRankedCount =
                 mChooserListAdapter.getCallerTargetCount()
                 + mChooserListAdapter.getRankedTargetCount();
         final int callerAndRankedRows = getCallerAndRankedTargetRowCount();
         if (position < callerAndRankedRows) {
             return serviceCount + position * mMaxTargetsPerRow;
         }

         position -= getAzLabelRowCount() + callerAndRankedRows;

         return callerAndRankedCount + serviceCount + position;
     }

     public void handleScroll(View v, int y, int oldy) {
         boolean canExpandDirectShare = canExpandDirectShare();
         if (mDirectShareViewHolder != null && canExpandDirectShare) {
             mChooserActivityDelegate.handleScrollToExpandDirectShare(
                     mDirectShareViewHolder, y, oldy);
         }
     }

     /** Only expand direct share area if there is a minimum number of targets. */
     private boolean canExpandDirectShare() {
         // Do not enable until we have confirmed more apps are using sharing shortcuts
         // Check git history for enablement logic
         return false;
     }

     public ChooserListAdapter getListAdapter() {
         return mChooserListAdapter;
     }

     public boolean shouldCellSpan(int position) {
         return getItemViewType(position) == VIEW_TYPE_NORMAL;
     }

     public void updateDirectShareExpansion() {
         if (mDirectShareViewHolder == null || !canExpandDirectShare()) {
             return;
         }
         mChooserActivityDelegate.updateDirectShareExpansion(mDirectShareViewHolder);
     }
 }
	/*
	* Copyright (C) 2008 The Android Open Source Project
	*
	* Licensed under the Apache License, Version 2.0 (the "License");
	* you may not use this file except in compliance with the License.
	* You may obtain a copy of the License at
	*
	* http://www.apache.org/licenses/LICENSE-2.0
	*
	* Unless required by applicable law or agreed to in writing, software
	* distributed under the License is distributed on an "AS IS" BASIS,
	* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
	* See the License for the specific language governing permissions and
	* limitations under the License.
	*/

	package com.android.intentresolver.grid;

	import android.animation.AnimatorSet;
	import android.animation.ObjectAnimator;
	import android.animation.ValueAnimator;
	import android.app.ActivityManager;
	import android.content.Context;
	import android.database.DataSetObserver;
	import android.view.LayoutInflater;
	import android.view.View;
	import android.view.View.MeasureSpec;
	import android.view.View.OnClickListener;
	import android.view.ViewGroup;
	import android.view.ViewGroup.LayoutParams;
	import android.view.animation.DecelerateInterpolator;
	import android.widget.Space;
	import android.widget.TextView;

	import androidx.recyclerview.widget.RecyclerView;

	import com.android.intentresolver.ChooserListAdapter;
	import com.android.intentresolver.R;
	import com.android.intentresolver.ResolverListAdapter.ViewHolder;
	import com.android.internal.annotations.VisibleForTesting;

	import com.google.android.collect.Lists;

	/**
	* Adapter for all types of items and targets in ShareSheet.
	* Note that ranked sections like Direct Share - while appearing grid-like - are handled on the
	* row level by this adapter but not on the item level. Individual targets within the row are
	* handled by {@link ChooserListAdapter}
	*/
	@VisibleForTesting
	public final class ChooserGridAdapter extends RecyclerView.Adapter<RecyclerView.ViewHolder> {

	/**
	* The transition time between placeholders for direct share to a message
	* indicating that none are available.
	*/
	public static final int NO_DIRECT_SHARE_ANIM_IN_MILLIS = 200;

	/**
	* Injectable interface for any considerations that should be delegated to other components
	* in the {@link ChooserActivity}.
	* TODO: determine whether any of these methods return parameters that can safely be
	* precomputed; whether any should be converted to `ChooserGridAdapter` setters to be
	* invoked by external callbacks; and whether any reflect requirements that should be moved
	* out of `ChooserGridAdapter` altogether.
	*/
	public interface ChooserActivityDelegate {
	/** @return whether we're showing a tabbed (multi-profile) UI. */
	boolean shouldShowTabs();

	/**
	* @return a content preview {@link View} that's appropriate for the caller's share
	* content, constructed for display in the provided {@code parent} group.
	*/
	View buildContentPreview(ViewGroup parent);

	/** Notify the client that the item with the selected {@code itemIndex} was selected. */
	void onTargetSelected(int itemIndex);

	/**
	* Notify the client that the item with the selected {@code itemIndex} was
	* long-pressed.
	*/
	void onTargetLongPressed(int itemIndex);

	/**
	* Notify the client that the provided {@code View} should be configured as the new
	* "profile view" button. Callers should attach their own click listeners to implement
	* behaviors on this view.
	*/
	void updateProfileViewButton(View newButtonFromProfileRow);

	/**
	* @return the number of "valid" targets in the active list adapter.
	* TODO: define "valid."
	*/
	int getValidTargetCount();

	/**
	* Request that the client update our {@code directShareGroup} to match their desired
	* state for the "expansion" UI.
	*/
	void updateDirectShareExpansion(DirectShareViewHolder directShareGroup);

	/**
	* Request that the client handle a scroll event that should be taken as expanding the
	* provided {@code directShareGroup}. Note that this currently never happens due to a
	* hard-coded condition in {@link #canExpandDirectShare()}.
	*/
	void handleScrollToExpandDirectShare(
	DirectShareViewHolder directShareGroup, int y, int oldy);
	}

	private static final int VIEW_TYPE_DIRECT_SHARE = 0;
	private static final int VIEW_TYPE_NORMAL = 1;
	private static final int VIEW_TYPE_CONTENT_PREVIEW = 2;
	private static final int VIEW_TYPE_PROFILE = 3;
	private static final int VIEW_TYPE_AZ_LABEL = 4;
	private static final int VIEW_TYPE_CALLER_AND_RANK = 5;
	private static final int VIEW_TYPE_FOOTER = 6;

	private static final int NUM_EXPANSIONS_TO_HIDE_AZ_LABEL = 20;

	private final ChooserActivityDelegate mChooserActivityDelegate;
	private final ChooserListAdapter mChooserListAdapter;
	private final LayoutInflater mLayoutInflater;

	private final int mMaxTargetsPerRow;
	private final boolean mShouldShowContentPreview;
	private final int mChooserWidthPixels;
	private final int mChooserRowTextOptionTranslatePixelSize;
	private final boolean mShowAzLabelIfPoss;

	private DirectShareViewHolder mDirectShareViewHolder;
	private int mChooserTargetWidth = 0;

	private int mFooterHeight = 0;

	public ChooserGridAdapter(
	Context context,
	ChooserActivityDelegate chooserActivityDelegate,
	ChooserListAdapter wrappedAdapter,
	boolean shouldShowContentPreview,
	int maxTargetsPerRow,
	int numSheetExpansions) {
	super();

	mChooserActivityDelegate = chooserActivityDelegate;

	mChooserListAdapter = wrappedAdapter;
	mLayoutInflater = LayoutInflater.from(context);

	mShouldShowContentPreview = shouldShowContentPreview;
	mMaxTargetsPerRow = maxTargetsPerRow;

	mChooserWidthPixels = context.getResources().getDimensionPixelSize(R.dimen.chooser_width);
	mChooserRowTextOptionTranslatePixelSize = context.getResources().getDimensionPixelSize(
	R.dimen.chooser_row_text_option_translate);

	mShowAzLabelIfPoss = numSheetExpansions < NUM_EXPANSIONS_TO_HIDE_AZ_LABEL;

	wrappedAdapter.registerDataSetObserver(new DataSetObserver() {
	@Override
	public void onChanged() {
	super.onChanged();
	notifyDataSetChanged();
	}

	@Override
	public void onInvalidated() {
	super.onInvalidated();
	notifyDataSetChanged();
	}
	});
	}

	public void setFooterHeight(int height) {
	mFooterHeight = height;
	}

	/**
	* Calculate the chooser target width to maximize space per item
	*
	* @param width The new row width to use for recalculation
	* @return true if the view width has changed
	*/
	public boolean calculateChooserTargetWidth(int width) {
	if (width == 0) {
	return false;
	}

	// Limit width to the maximum width of the chooser activity
	int maxWidth = mChooserWidthPixels;
	width = Math.min(maxWidth, width);

	int newWidth = width / mMaxTargetsPerRow;
	if (newWidth != mChooserTargetWidth) {
	mChooserTargetWidth = newWidth;
	return true;
	}

	return false;
	}

	public int getRowCount() {
	return (int) (
	getSystemRowCount()
	+ getProfileRowCount()
	+ getServiceTargetRowCount()
	+ getCallerAndRankedTargetRowCount()
	+ getAzLabelRowCount()
	+ Math.ceil(
	(float) mChooserListAdapter.getAlphaTargetCount()
	/ mMaxTargetsPerRow)
	);
	}

	/**
	* Whether the "system" row of targets is displayed.
	* This area includes the content preview (if present) and action row.
	*/
	public int getSystemRowCount() {
	// For the tabbed case we show the sticky content preview above the tabs,
	// please refer to shouldShowStickyContentPreview
	if (mChooserActivityDelegate.shouldShowTabs()) {
	return 0;
	}

	if (!mShouldShowContentPreview) {
	return 0;
	}

	if (mChooserListAdapter == null \|\| mChooserListAdapter.getCount() == 0) {
	return 0;
	}

	return 1;
	}

	public int getProfileRowCount() {
	if (mChooserActivityDelegate.shouldShowTabs()) {
	return 0;
	}
	return mChooserListAdapter.getOtherProfile() == null ? 0 : 1;
	}

	public int getFooterRowCount() {
	return 1;
	}

	public int getCallerAndRankedTargetRowCount() {
	return (int) Math.ceil(
	((float) mChooserListAdapter.getCallerTargetCount()
	+ mChooserListAdapter.getRankedTargetCount()) / mMaxTargetsPerRow);
	}

	// There can be at most one row in the listview, that is internally
	// a ViewGroup with 2 rows
	public int getServiceTargetRowCount() {
	if (mShouldShowContentPreview && !ActivityManager.isLowRamDeviceStatic()) {
	return 1;
	}
	return 0;
	}

	public int getAzLabelRowCount() {
	// Only show a label if the a-z list is showing
	return (mShowAzLabelIfPoss && mChooserListAdapter.getAlphaTargetCount() > 0) ? 1 : 0;
	}

	@Override
	public int getItemCount() {
	return (int) (
	getSystemRowCount()
	+ getProfileRowCount()
	+ getServiceTargetRowCount()
	+ getCallerAndRankedTargetRowCount()
	+ getAzLabelRowCount()
	+ mChooserListAdapter.getAlphaTargetCount()
	+ getFooterRowCount()
	);
	}

	@Override
	public RecyclerView.ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
	switch (viewType) {
	case VIEW_TYPE_CONTENT_PREVIEW:
	return new ItemViewHolder(
	mChooserActivityDelegate.buildContentPreview(parent),
	viewType,
	null,
	null);
	case VIEW_TYPE_PROFILE:
	return new ItemViewHolder(
	createProfileView(parent),
	viewType,
	null,
	null);
	case VIEW_TYPE_AZ_LABEL:
	return new ItemViewHolder(
	createAzLabelView(parent),
	viewType,
	null,
	null);
	case VIEW_TYPE_NORMAL:
	return new ItemViewHolder(
	mChooserListAdapter.createView(parent),
	viewType,
	mChooserActivityDelegate::onTargetSelected,
	mChooserActivityDelegate::onTargetLongPressed);
	case VIEW_TYPE_DIRECT_SHARE:
	case VIEW_TYPE_CALLER_AND_RANK:
	return createItemGroupViewHolder(viewType, parent);
	case VIEW_TYPE_FOOTER:
	Space sp = new Space(parent.getContext());
	sp.setLayoutParams(new RecyclerView.LayoutParams(
	LayoutParams.MATCH_PARENT, mFooterHeight));
	return new FooterViewHolder(sp, viewType);
	default:
	// Since we catch all possible viewTypes above, no chance this is being called.
	return null;
	}
	}

	@Override
	public void onBindViewHolder(RecyclerView.ViewHolder holder, int position) {
	int viewType = ((ViewHolderBase) holder).getViewType();
	switch (viewType) {
	case VIEW_TYPE_DIRECT_SHARE:
	case VIEW_TYPE_CALLER_AND_RANK:
	bindItemGroupViewHolder(position, (ItemGroupViewHolder) holder);
	break;
	case VIEW_TYPE_NORMAL:
	bindItemViewHolder(position, (ItemViewHolder) holder);
	break;
	default:
	}
	}

	@Override
	public int getItemViewType(int position) {
	int count;

	int countSum = (count = getSystemRowCount());
	if (count > 0 && position < countSum) return VIEW_TYPE_CONTENT_PREVIEW;

	countSum += (count = getProfileRowCount());
	if (count > 0 && position < countSum) return VIEW_TYPE_PROFILE;

	countSum += (count = getServiceTargetRowCount());
	if (count > 0 && position < countSum) return VIEW_TYPE_DIRECT_SHARE;

	countSum += (count = getCallerAndRankedTargetRowCount());
	if (count > 0 && position < countSum) return VIEW_TYPE_CALLER_AND_RANK;

	countSum += (count = getAzLabelRowCount());
	if (count > 0 && position < countSum) return VIEW_TYPE_AZ_LABEL;

	if (position == getItemCount() - 1) return VIEW_TYPE_FOOTER;

	return VIEW_TYPE_NORMAL;
	}

	public int getTargetType(int position) {
	return mChooserListAdapter.getPositionTargetType(getListPosition(position));
	}

	private View createProfileView(ViewGroup parent) {
	View profileRow = mLayoutInflater.inflate(R.layout.chooser_profile_row, parent, false);
	mChooserActivityDelegate.updateProfileViewButton(profileRow);
	return profileRow;
	}

	private View createAzLabelView(ViewGroup parent) {
	return mLayoutInflater.inflate(R.layout.chooser_az_label_row, parent, false);
	}

	private ItemGroupViewHolder loadViewsIntoGroup(ItemGroupViewHolder holder) {
	final int spec = MeasureSpec.makeMeasureSpec(0, MeasureSpec.UNSPECIFIED);
	final int exactSpec = MeasureSpec.makeMeasureSpec(mChooserTargetWidth, MeasureSpec.EXACTLY);
	int columnCount = holder.getColumnCount();

	final boolean isDirectShare = holder instanceof DirectShareViewHolder;

	for (int i = 0; i < columnCount; i++) {
	final View v = mChooserListAdapter.createView(holder.getRowByIndex(i));
	final int column = i;
	v.setOnClickListener(new OnClickListener() {
	@Override
	public void onClick(View v) {
	mChooserActivityDelegate.onTargetSelected(holder.getItemIndex(column));
	}
	});

	// Show menu for both direct share and app share targets after long click.
	v.setOnLongClickListener(v1 -> {
	mChooserActivityDelegate.onTargetLongPressed(holder.getItemIndex(column));
	return true;
	});

	holder.addView(i, v);

	// Force Direct Share to be 2 lines and auto-wrap to second line via hoz scroll =
	// false. TextView#setHorizontallyScrolling must be reset after #setLines. Must be
	// done before measuring.
	if (isDirectShare) {
	final ViewHolder vh = (ViewHolder) v.getTag();
	vh.text.setLines(2);
	vh.text.setHorizontallyScrolling(false);
	vh.text2.setVisibility(View.GONE);
	}

	// Force height to be a given so we don't have visual disruption during scaling.
	v.measure(exactSpec, spec);
	setViewBounds(v, v.getMeasuredWidth(), v.getMeasuredHeight());
	}

	final ViewGroup viewGroup = holder.getViewGroup();

	// Pre-measure and fix height so we can scale later.
	holder.measure();
	setViewBounds(viewGroup, LayoutParams.MATCH_PARENT, holder.getMeasuredRowHeight());

	if (isDirectShare) {
	DirectShareViewHolder dsvh = (DirectShareViewHolder) holder;
	setViewBounds(dsvh.getRow(0), LayoutParams.MATCH_PARENT, dsvh.getMinRowHeight());
	setViewBounds(dsvh.getRow(1), LayoutParams.MATCH_PARENT, dsvh.getMinRowHeight());
	}

	viewGroup.setTag(holder);
	return holder;
	}

	private void setViewBounds(View view, int widthPx, int heightPx) {
	LayoutParams lp = view.getLayoutParams();
	if (lp == null) {
	lp = new LayoutParams(widthPx, heightPx);
	view.setLayoutParams(lp);
	} else {
	lp.height = heightPx;
	lp.width = widthPx;
	}
	}

	ItemGroupViewHolder createItemGroupViewHolder(int viewType, ViewGroup parent) {
	if (viewType == VIEW_TYPE_DIRECT_SHARE) {
	ViewGroup parentGroup = (ViewGroup) mLayoutInflater.inflate(
	R.layout.chooser_row_direct_share, parent, false);
	ViewGroup row1 = (ViewGroup) mLayoutInflater.inflate(
	R.layout.chooser_row, parentGroup, false);
	ViewGroup row2 = (ViewGroup) mLayoutInflater.inflate(
	R.layout.chooser_row, parentGroup, false);
	parentGroup.addView(row1);
	parentGroup.addView(row2);

	mDirectShareViewHolder = new DirectShareViewHolder(parentGroup,
	Lists.newArrayList(row1, row2), mMaxTargetsPerRow, viewType,
	mChooserActivityDelegate::getValidTargetCount);
	loadViewsIntoGroup(mDirectShareViewHolder);

	return mDirectShareViewHolder;
	} else {
	ViewGroup row = (ViewGroup) mLayoutInflater.inflate(
	R.layout.chooser_row, parent, false);
	ItemGroupViewHolder holder =
	new SingleRowViewHolder(row, mMaxTargetsPerRow, viewType);
	loadViewsIntoGroup(holder);

	return holder;
	}
	}

	/**
	* Need to merge CALLER + ranked STANDARD into a single row and prevent a separator from
	* showing on top of the AZ list if the AZ label is visible. All other types are placed into
	* their own row as determined by their target type, and dividers are added in the list to
	* separate each type.
	*/
	int getRowType(int rowPosition) {
	// Merge caller and ranked standard into a single row
	int positionType = mChooserListAdapter.getPositionTargetType(rowPosition);
	if (positionType == ChooserListAdapter.TARGET_CALLER) {
	return ChooserListAdapter.TARGET_STANDARD;
	}

	// If an A-Z label is shown, prevent a separator from appearing by making the A-Z
	// row type the same as the suggestion row type
	if (getAzLabelRowCount() > 0 && positionType == ChooserListAdapter.TARGET_STANDARD_AZ) {
	return ChooserListAdapter.TARGET_STANDARD;
	}

	return positionType;
	}

	void bindItemViewHolder(int position, ItemViewHolder holder) {
	View v = holder.itemView;
	int listPosition = getListPosition(position);
	holder.setListPosition(listPosition);
	mChooserListAdapter.bindView(listPosition, v);
	}

	void bindItemGroupViewHolder(int position, ItemGroupViewHolder holder) {
	final ViewGroup viewGroup = (ViewGroup) holder.itemView;
	int start = getListPosition(position);
	int startType = getRowType(start);

	int columnCount = holder.getColumnCount();
	int end = start + columnCount - 1;
	while (getRowType(end) != startType && end >= start) {
	end--;
	}

	if (end == start && mChooserListAdapter.getItem(start).isEmptyTargetInfo()) {
	final TextView textView = viewGroup.findViewById(
	com.android.internal.R.id.chooser_row_text_option);

	if (textView.getVisibility() != View.VISIBLE) {
	textView.setAlpha(0.0f);
	textView.setVisibility(View.VISIBLE);
	textView.setText(R.string.chooser_no_direct_share_targets);

	ValueAnimator fadeAnim = ObjectAnimator.ofFloat(textView, "alpha", 0.0f, 1.0f);
	fadeAnim.setInterpolator(new DecelerateInterpolator(1.0f));

	textView.setTranslationY(mChooserRowTextOptionTranslatePixelSize);
	ValueAnimator translateAnim =
	ObjectAnimator.ofFloat(textView, "translationY", 0.0f);
	translateAnim.setInterpolator(new DecelerateInterpolator(1.0f));

	AnimatorSet animSet = new AnimatorSet();
	animSet.setDuration(NO_DIRECT_SHARE_ANIM_IN_MILLIS);
	animSet.setStartDelay(NO_DIRECT_SHARE_ANIM_IN_MILLIS);
	animSet.playTogether(fadeAnim, translateAnim);
	animSet.start();
	}
	}

	for (int i = 0; i < columnCount; i++) {
	final View v = holder.getView(i);

	if (start + i <= end) {
	holder.setViewVisibility(i, View.VISIBLE);
	holder.setItemIndex(i, start + i);
	mChooserListAdapter.bindView(holder.getItemIndex(i), v);
	} else {
	holder.setViewVisibility(i, View.INVISIBLE);
	}
	}
	}

	int getListPosition(int position) {
	position -= getSystemRowCount() + getProfileRowCount();

	final int serviceCount = mChooserListAdapter.getServiceTargetCount();
	final int serviceRows = (int) Math.ceil((float) serviceCount / mMaxTargetsPerRow);
	if (position < serviceRows) {
	return position * mMaxTargetsPerRow;
	}

	position -= serviceRows;

	final int callerAndRankedCount =
	mChooserListAdapter.getCallerTargetCount()
	+ mChooserListAdapter.getRankedTargetCount();
	final int callerAndRankedRows = getCallerAndRankedTargetRowCount();
	if (position < callerAndRankedRows) {
	return serviceCount + position * mMaxTargetsPerRow;
	}

	position -= getAzLabelRowCount() + callerAndRankedRows;

	return callerAndRankedCount + serviceCount + position;
	}

	public void handleScroll(View v, int y, int oldy) {
	boolean canExpandDirectShare = canExpandDirectShare();
	if (mDirectShareViewHolder != null && canExpandDirectShare) {
	mChooserActivityDelegate.handleScrollToExpandDirectShare(
	mDirectShareViewHolder, y, oldy);
	}
	}

	/** Only expand direct share area if there is a minimum number of targets. */
	private boolean canExpandDirectShare() {
	// Do not enable until we have confirmed more apps are using sharing shortcuts
	// Check git history for enablement logic
	return false;
	}

	public ChooserListAdapter getListAdapter() {
	return mChooserListAdapter;
	}

	public boolean shouldCellSpan(int position) {
	return getItemViewType(position) == VIEW_TYPE_NORMAL;
	}

	public void updateDirectShareExpansion() {
	if (mDirectShareViewHolder == null \|\| !canExpandDirectShare()) {
	return;
	}
	mChooserActivityDelegate.updateDirectShareExpansion(mDirectShareViewHolder);
	}
	}