src/com/android/launcher3/folder/FolderPagedView.java - LeafOS-Project/android_packages_apps_Launcher3 - Gitiles

 /*
  * Copyright (C) 2015 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.launcher3.folder;

 import android.annotation.SuppressLint;
 import android.content.Context;
 import android.graphics.Canvas;
 import android.graphics.drawable.Drawable;
 import android.util.ArrayMap;
 import android.util.AttributeSet;
 import android.util.Log;
 import android.view.Gravity;
 import android.view.LayoutInflater;
 import android.view.View;
 import android.view.ViewDebug;

 import com.android.launcher3.BubbleTextView;
 import com.android.launcher3.CellLayout;
 import com.android.launcher3.DeviceProfile;
 import com.android.launcher3.InvariantDeviceProfile;
 import com.android.launcher3.ItemInfo;
 import com.android.launcher3.Launcher;
 import com.android.launcher3.LauncherAppState;
 import com.android.launcher3.PagedView;
 import com.android.launcher3.R;
 import com.android.launcher3.ShortcutAndWidgetContainer;
 import com.android.launcher3.WorkspaceItemInfo;
 import com.android.launcher3.Utilities;
 import com.android.launcher3.Workspace.ItemOperator;
 import com.android.launcher3.anim.Interpolators;
 import com.android.launcher3.keyboard.ViewGroupFocusHelper;
 import com.android.launcher3.pageindicators.PageIndicatorDots;
 import com.android.launcher3.touch.ItemClickHandler;
 import com.android.launcher3.util.Thunk;

 import java.util.ArrayList;
 import java.util.Iterator;
 import java.util.Map;

 public class FolderPagedView extends PagedView<PageIndicatorDots> {

     private static final String TAG = "FolderPagedView";

     private static final int REORDER_ANIMATION_DURATION = 230;
     private static final int START_VIEW_REORDER_DELAY = 30;
     private static final float VIEW_REORDER_DELAY_FACTOR = 0.9f;

     /**
      * Fraction of the width to scroll when showing the next page hint.
      */
     private static final float SCROLL_HINT_FRACTION = 0.07f;

     private static final int[] sTmpArray = new int[2];

     public final boolean mIsRtl;

     private final LayoutInflater mInflater;
     private final ViewGroupFocusHelper mFocusIndicatorHelper;

     @Thunk final ArrayMap<View, Runnable> mPendingAnimations = new ArrayMap<>();

     @ViewDebug.ExportedProperty(category = "launcher")
     private final int mMaxCountX;
     @ViewDebug.ExportedProperty(category = "launcher")
     private final int mMaxCountY;
     @ViewDebug.ExportedProperty(category = "launcher")
     private final int mMaxItemsPerPage;

     private int mAllocatedContentSize;
     @ViewDebug.ExportedProperty(category = "launcher")
     private int mGridCountX;
     @ViewDebug.ExportedProperty(category = "launcher")
     private int mGridCountY;

     private Folder mFolder;

     public FolderPagedView(Context context, AttributeSet attrs) {
         super(context, attrs);
         InvariantDeviceProfile profile = LauncherAppState.getIDP(context);
         mMaxCountX = profile.numFolderColumns;
         mMaxCountY = profile.numFolderRows;

         mMaxItemsPerPage = mMaxCountX * mMaxCountY;

         mInflater = LayoutInflater.from(context);

         mIsRtl = Utilities.isRtl(getResources());
         setImportantForAccessibility(IMPORTANT_FOR_ACCESSIBILITY_YES);

         mFocusIndicatorHelper = new ViewGroupFocusHelper(this);
     }

     public void setFolder(Folder folder) {
         mFolder = folder;
         mPageIndicator = folder.findViewById(R.id.folder_page_indicator);
         initParentViews(folder);
     }

     /**
      * Calculates the grid size such that {@param count} items can fit in the grid.
      * The grid size is calculated such that countY <= countX and countX = ceil(sqrt(count)) while
      * maintaining the restrictions of {@link #mMaxCountX} &amp; {@link #mMaxCountY}.
      */
     public static void calculateGridSize(int count, int countX, int countY, int maxCountX,
             int maxCountY, int maxItemsPerPage, int[] out) {
         boolean done;
         int gridCountX = countX;
         int gridCountY = countY;

         if (count >= maxItemsPerPage) {
             gridCountX = maxCountX;
             gridCountY = maxCountY;
             done = true;
         } else {
             done = false;
         }

         while (!done) {
             int oldCountX = gridCountX;
             int oldCountY = gridCountY;
             if (gridCountX * gridCountY < count) {
                 // Current grid is too small, expand it
                 if ((gridCountX <= gridCountY || gridCountY == maxCountY)
                         && gridCountX < maxCountX) {
                     gridCountX++;
                 } else if (gridCountY < maxCountY) {
                     gridCountY++;
                 }
                 if (gridCountY == 0) gridCountY++;
             } else if ((gridCountY - 1) * gridCountX >= count && gridCountY >= gridCountX) {
                 gridCountY = Math.max(0, gridCountY - 1);
             } else if ((gridCountX - 1) * gridCountY >= count) {
                 gridCountX = Math.max(0, gridCountX - 1);
             }
             done = gridCountX == oldCountX && gridCountY == oldCountY;
         }

         out[0] = gridCountX;
         out[1] = gridCountY;
     }

     /**
      * Sets up the grid size such that {@param count} items can fit in the grid.
      */
     public void setupContentDimensions(int count) {
         mAllocatedContentSize = count;
         calculateGridSize(count, mGridCountX, mGridCountY, mMaxCountX, mMaxCountY, mMaxItemsPerPage,
                 sTmpArray);
         mGridCountX = sTmpArray[0];
         mGridCountY = sTmpArray[1];

         // Update grid size
         for (int i = getPageCount() - 1; i >= 0; i--) {
             getPageAt(i).setGridSize(mGridCountX, mGridCountY);
         }
     }

     @Override
     protected void dispatchDraw(Canvas canvas) {
         mFocusIndicatorHelper.draw(canvas);
         super.dispatchDraw(canvas);
     }

     /**
      * Binds items to the layout.
      */
     public void bindItems(ArrayList<WorkspaceItemInfo> items) {
         ArrayList<View> icons = new ArrayList<>();
         for (WorkspaceItemInfo item : items) {
             icons.add(createNewView(item));
         }
         arrangeChildren(icons, icons.size(), false);
     }

     public void allocateSpaceForRank(int rank) {
         ArrayList<View> views = new ArrayList<>(mFolder.getItemsInReadingOrder());
         views.add(rank, null);
         arrangeChildren(views, views.size(), false);
     }

     /**
      * Create space for a new item at the end, and returns the rank for that item.
      * Also sets the current page to the last page.
      */
     public int allocateRankForNewItem() {
         int rank = getItemCount();
         allocateSpaceForRank(rank);
         setCurrentPage(rank / mMaxItemsPerPage);
         return rank;
     }

     public View createAndAddViewForRank(WorkspaceItemInfo item, int rank) {
         View icon = createNewView(item);
         allocateSpaceForRank(rank);
         addViewForRank(icon, item, rank);
         return icon;
     }

     /**
      * Adds the {@param view} to the layout based on {@param rank} and updated the position
      * related attributes. It assumes that {@param item} is already attached to the view.
      */
     public void addViewForRank(View view, WorkspaceItemInfo item, int rank) {
         int pagePos = rank % mMaxItemsPerPage;
         int pageNo = rank / mMaxItemsPerPage;

         item.rank = rank;
         item.cellX = pagePos % mGridCountX;
         item.cellY = pagePos / mGridCountX;

         CellLayout.LayoutParams lp = (CellLayout.LayoutParams) view.getLayoutParams();
         lp.cellX = item.cellX;
         lp.cellY = item.cellY;
         getPageAt(pageNo).addViewToCellLayout(view, -1, item.getViewId(), lp, true);
     }

     @SuppressLint("InflateParams")
     public View createNewView(WorkspaceItemInfo item) {
         final BubbleTextView textView = (BubbleTextView) mInflater.inflate(
                 R.layout.folder_application, null, false);
         textView.applyFromWorkspaceItem(item);
         textView.setHapticFeedbackEnabled(false);
         textView.setOnClickListener(ItemClickHandler.INSTANCE);
         textView.setOnLongClickListener(mFolder);
         textView.setOnFocusChangeListener(mFocusIndicatorHelper);

         textView.setLayoutParams(new CellLayout.LayoutParams(
                 item.cellX, item.cellY, item.spanX, item.spanY));
         return textView;
     }

     @Override
     public CellLayout getPageAt(int index) {
         return (CellLayout) getChildAt(index);
     }

     public CellLayout getCurrentCellLayout() {
         return getPageAt(getNextPage());
     }

     private CellLayout createAndAddNewPage() {
         DeviceProfile grid = Launcher.getLauncher(getContext()).getDeviceProfile();
         CellLayout page = (CellLayout) mInflater.inflate(R.layout.folder_page, this, false);
         page.setCellDimensions(grid.folderCellWidthPx, grid.folderCellHeightPx);
         page.getShortcutsAndWidgets().setMotionEventSplittingEnabled(false);
         page.setInvertIfRtl(true);
         page.setGridSize(mGridCountX, mGridCountY);

         addView(page, -1, generateDefaultLayoutParams());
         return page;
     }

     @Override
     protected int getChildGap() {
         return getPaddingLeft() + getPaddingRight();
     }

     public void setFixedSize(int width, int height) {
         width -= (getPaddingLeft() + getPaddingRight());
         height -= (getPaddingTop() + getPaddingBottom());
         for (int i = getChildCount() - 1; i >= 0; i --) {
             ((CellLayout) getChildAt(i)).setFixedSize(width, height);
         }
     }

     public void removeItem(View v) {
         for (int i = getChildCount() - 1; i >= 0; i --) {
             getPageAt(i).removeView(v);
         }
     }

     @Override
     protected void onScrollChanged(int l, int t, int oldl, int oldt) {
         super.onScrollChanged(l, t, oldl, oldt);
         mPageIndicator.setScroll(l, mMaxScrollX);
     }

     /**
      * Updates position and rank of all the children in the view.
      * It essentially removes all views from all the pages and then adds them again in appropriate
      * page.
      *
      * @param list the ordered list of children.
      * @param itemCount if greater than the total children count, empty spaces are left
      * at the end, otherwise it is ignored.
      *
      */
     public void arrangeChildren(ArrayList<View> list, int itemCount) {
         arrangeChildren(list, itemCount, true);
     }

     @SuppressLint("RtlHardcoded")
     private void arrangeChildren(ArrayList<View> list, int itemCount, boolean saveChanges) {
         ArrayList<CellLayout> pages = new ArrayList<>();
         for (int i = 0; i < getChildCount(); i++) {
             CellLayout page = (CellLayout) getChildAt(i);
             page.removeAllViews();
             pages.add(page);
         }
         setupContentDimensions(itemCount);

         Iterator<CellLayout> pageItr = pages.iterator();
         CellLayout currentPage = null;

         int position = 0;
         int newX, newY, rank;

         FolderIconPreviewVerifier verifier = new FolderIconPreviewVerifier(
                 Launcher.getLauncher(getContext()).getDeviceProfile().inv);
         verifier.setFolderInfo(mFolder.getInfo());
         rank = 0;
         for (int i = 0; i < itemCount; i++) {
             View v = list.size() > i ? list.get(i) : null;
             if (currentPage == null || position >= mMaxItemsPerPage) {
                 // Next page
                 if (pageItr.hasNext()) {
                     currentPage = pageItr.next();
                 } else {
                     currentPage = createAndAddNewPage();
                 }
                 position = 0;
             }

             if (v != null) {
                 CellLayout.LayoutParams lp = (CellLayout.LayoutParams) v.getLayoutParams();
                 newX = position % mGridCountX;
                 newY = position / mGridCountX;
                 ItemInfo info = (ItemInfo) v.getTag();
                 if (info.cellX != newX || info.cellY != newY || info.rank != rank) {
                     info.cellX = newX;
                     info.cellY = newY;
                     info.rank = rank;
                     if (saveChanges) {
                         mFolder.mLauncher.getModelWriter().addOrMoveItemInDatabase(info,
                                 mFolder.mInfo.id, 0, info.cellX, info.cellY);
                     }
                 }
                 lp.cellX = info.cellX;
                 lp.cellY = info.cellY;
                 currentPage.addViewToCellLayout(v, -1, info.getViewId(), lp, true);

                 if (verifier.isItemInPreview(rank) && v instanceof BubbleTextView) {
                     ((BubbleTextView) v).verifyHighRes();
                 }
             }

             rank ++;
             position++;
         }

         // Remove extra views.
         boolean removed = false;
         while (pageItr.hasNext()) {
             removeView(pageItr.next());
             removed = true;
         }
         if (removed) {
             setCurrentPage(0);
         }

         setEnableOverscroll(getPageCount() > 1);

         // Update footer
         mPageIndicator.setVisibility(getPageCount() > 1 ? View.VISIBLE : View.GONE);
         // Set the gravity as LEFT or RIGHT instead of START, as START depends on the actual text.
         mFolder.mFolderName.setGravity(getPageCount() > 1 ?
                 (mIsRtl ? Gravity.RIGHT : Gravity.LEFT) : Gravity.CENTER_HORIZONTAL);
     }

     public int getDesiredWidth() {
         return getPageCount() > 0 ?
                 (getPageAt(0).getDesiredWidth() + getPaddingLeft() + getPaddingRight()) : 0;
     }

     public int getDesiredHeight()  {
         return  getPageCount() > 0 ?
                 (getPageAt(0).getDesiredHeight() + getPaddingTop() + getPaddingBottom()) : 0;
     }

     public int getItemCount() {
         int lastPageIndex = getChildCount() - 1;
         if (lastPageIndex < 0) {
             // If there are no pages, nothing has yet been added to the folder.
             return 0;
         }
         return getPageAt(lastPageIndex).getShortcutsAndWidgets().getChildCount()
                 + lastPageIndex * mMaxItemsPerPage;
     }

     /**
      * @return the rank of the cell nearest to the provided pixel position.
      */
     public int findNearestArea(int pixelX, int pixelY) {
         int pageIndex = getNextPage();
         CellLayout page = getPageAt(pageIndex);
         page.findNearestArea(pixelX, pixelY, 1, 1, sTmpArray);
         if (mFolder.isLayoutRtl()) {
             sTmpArray[0] = page.getCountX() - sTmpArray[0] - 1;
         }
         return Math.min(mAllocatedContentSize - 1,
                 pageIndex * mMaxItemsPerPage + sTmpArray[1] * mGridCountX + sTmpArray[0]);
     }

     public View getFirstItem() {
         if (getChildCount() < 1) {
             return null;
         }
         ShortcutAndWidgetContainer currContainer = getCurrentCellLayout().getShortcutsAndWidgets();
         if (mGridCountX > 0) {
             return currContainer.getChildAt(0, 0);
         } else {
             return currContainer.getChildAt(0);
         }
     }

     public View getLastItem() {
         if (getChildCount() < 1) {
             return null;
         }
         ShortcutAndWidgetContainer currContainer = getCurrentCellLayout().getShortcutsAndWidgets();
         int lastRank = currContainer.getChildCount() - 1;
         if (mGridCountX > 0) {
             return currContainer.getChildAt(lastRank % mGridCountX, lastRank / mGridCountX);
         } else {
             return currContainer.getChildAt(lastRank);
         }
     }

     /**
      * Iterates over all its items in a reading order.
      * @return the view for which the operator returned true.
      */
     public View iterateOverItems(ItemOperator op) {
         for (int k = 0 ; k < getChildCount(); k++) {
             CellLayout page = getPageAt(k);
             for (int j = 0; j < page.getCountY(); j++) {
                 for (int i = 0; i < page.getCountX(); i++) {
                     View v = page.getChildAt(i, j);
                     if ((v != null) && op.evaluate((ItemInfo) v.getTag(), v)) {
                         return v;
                     }
                 }
             }
         }
         return null;
     }

     public String getAccessibilityDescription() {
         return getContext().getString(R.string.folder_opened, mGridCountX, mGridCountY);
     }

     /**
      * Sets the focus on the first visible child.
      */
     public void setFocusOnFirstChild() {
         View firstChild = getCurrentCellLayout().getChildAt(0, 0);
         if (firstChild != null) {
             firstChild.requestFocus();
         }
     }

     @Override
     protected void notifyPageSwitchListener(int prevPage) {
         super.notifyPageSwitchListener(prevPage);
         if (mFolder != null) {
             mFolder.updateTextViewFocus();
         }
     }

     /**
      * Scrolls the current view by a fraction
      */
     public void showScrollHint(int direction) {
         float fraction = (direction == Folder.SCROLL_LEFT) ^ mIsRtl
                 ? -SCROLL_HINT_FRACTION : SCROLL_HINT_FRACTION;
         int hint = (int) (fraction * getWidth());
         int scroll = getScrollForPage(getNextPage()) + hint;
         int delta = scroll - getScrollX();
         if (delta != 0) {
             mScroller.setInterpolator(Interpolators.DEACCEL);
             mScroller.startScroll(getScrollX(), delta, Folder.SCROLL_HINT_DURATION);
             invalidate();
         }
     }

     public void clearScrollHint() {
         if (getScrollX() != getScrollForPage(getNextPage())) {
             snapToPage(getNextPage());
         }
     }

     /**
      * Finish animation all the views which are animating across pages
      */
     public void completePendingPageChanges() {
         if (!mPendingAnimations.isEmpty()) {
             ArrayMap<View, Runnable> pendingViews = new ArrayMap<>(mPendingAnimations);
             for (Map.Entry<View, Runnable> e : pendingViews.entrySet()) {
                 e.getKey().animate().cancel();
                 e.getValue().run();
             }
         }
     }

     public boolean rankOnCurrentPage(int rank) {
         int p = rank / mMaxItemsPerPage;
         return p == getNextPage();
     }

     @Override
     protected void onPageBeginTransition() {
         super.onPageBeginTransition();
         // Ensure that adjacent pages have high resolution icons
         verifyVisibleHighResIcons(getCurrentPage() - 1);
         verifyVisibleHighResIcons(getCurrentPage() + 1);
     }

     /**
      * Ensures that all the icons on the given page are of high-res
      */
     public void verifyVisibleHighResIcons(int pageNo) {
         CellLayout page = getPageAt(pageNo);
         if (page != null) {
             ShortcutAndWidgetContainer parent = page.getShortcutsAndWidgets();
             for (int i = parent.getChildCount() - 1; i >= 0; i--) {
                 BubbleTextView icon = ((BubbleTextView) parent.getChildAt(i));
                 icon.verifyHighRes();
                 // Set the callback back to the actual icon, in case
                 // it was captured by the FolderIcon
                 Drawable d = icon.getCompoundDrawables()[1];
                 if (d != null) {
                     d.setCallback(icon);
                 }
             }
         }
     }

     public int getAllocatedContentSize() {
         return mAllocatedContentSize;
     }

     /**
      * Reorders the items such that the {@param empty} spot moves to {@param target}
      */
     public void realTimeReorder(int empty, int target) {
         completePendingPageChanges();
         int delay = 0;
         float delayAmount = START_VIEW_REORDER_DELAY;

         // Animation only happens on the current page.
         int pageToAnimate = getNextPage();

         int pageT = target / mMaxItemsPerPage;
         int pagePosT = target % mMaxItemsPerPage;

         if (pageT != pageToAnimate) {
             Log.e(TAG, "Cannot animate when the target cell is invisible");
         }
         int pagePosE = empty % mMaxItemsPerPage;
         int pageE = empty / mMaxItemsPerPage;

         int startPos, endPos;
         int moveStart, moveEnd;
         int direction;

         if (target == empty) {
             // No animation
             return;
         } else if (target > empty) {
             // Items will move backwards to make room for the empty cell.
             direction = 1;

             // If empty cell is in a different page, move them instantly.
             if (pageE < pageToAnimate) {
                 moveStart = empty;
                 // Instantly move the first item in the current page.
                 moveEnd = pageToAnimate * mMaxItemsPerPage;
                 // Animate the 2nd item in the current page, as the first item was already moved to
                 // the last page.
                 startPos = 0;
             } else {
                 moveStart = moveEnd = -1;
                 startPos = pagePosE;
             }

             endPos = pagePosT;
         } else {
             // The items will move forward.
             direction = -1;

             if (pageE > pageToAnimate) {
                 // Move the items immediately.
                 moveStart = empty;
                 // Instantly move the last item in the current page.
                 moveEnd = (pageToAnimate + 1) * mMaxItemsPerPage - 1;

                 // Animations start with the second last item in the page
                 startPos = mMaxItemsPerPage - 1;
             } else {
                 moveStart = moveEnd = -1;
                 startPos = pagePosE;
             }

             endPos = pagePosT;
         }

         // Instant moving views.
         while (moveStart != moveEnd) {
             int rankToMove = moveStart + direction;
             int p = rankToMove / mMaxItemsPerPage;
             int pagePos = rankToMove % mMaxItemsPerPage;
             int x = pagePos % mGridCountX;
             int y = pagePos / mGridCountX;

             final CellLayout page = getPageAt(p);
             final View v = page.getChildAt(x, y);
             if (v != null) {
                 if (pageToAnimate != p) {
                     page.removeView(v);
                     addViewForRank(v, (WorkspaceItemInfo) v.getTag(), moveStart);
                 } else {
                     // Do a fake animation before removing it.
                     final int newRank = moveStart;
                     final float oldTranslateX = v.getTranslationX();

                     Runnable endAction = new Runnable() {

                         @Override
                         public void run() {
                             mPendingAnimations.remove(v);
                             v.setTranslationX(oldTranslateX);
                             ((CellLayout) v.getParent().getParent()).removeView(v);
                             addViewForRank(v, (WorkspaceItemInfo) v.getTag(), newRank);
                         }
                     };
                     v.animate()
                         .translationXBy((direction > 0 ^ mIsRtl) ? -v.getWidth() : v.getWidth())
                         .setDuration(REORDER_ANIMATION_DURATION)
                         .setStartDelay(0)
                         .withEndAction(endAction);
                     mPendingAnimations.put(v, endAction);
                 }
             }
             moveStart = rankToMove;
         }

         if ((endPos - startPos) * direction <= 0) {
             // No animation
             return;
         }

         CellLayout page = getPageAt(pageToAnimate);
         for (int i = startPos; i != endPos; i += direction) {
             int nextPos = i + direction;
             View v = page.getChildAt(nextPos % mGridCountX, nextPos / mGridCountX);
             if (v != null) {
                 ((ItemInfo) v.getTag()).rank -= direction;
             }
             if (page.animateChildToPosition(v, i % mGridCountX, i / mGridCountX,
                     REORDER_ANIMATION_DURATION, delay, true, true)) {
                 delay += delayAmount;
                 delayAmount *= VIEW_REORDER_DELAY_FACTOR;
             }
         }
     }

     public int itemsPerPage() {
         return mMaxItemsPerPage;
     }
 }
	/*
	* Copyright (C) 2015 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.launcher3.folder;

	import android.annotation.SuppressLint;
	import android.content.Context;
	import android.graphics.Canvas;
	import android.graphics.drawable.Drawable;
	import android.util.ArrayMap;
	import android.util.AttributeSet;
	import android.util.Log;
	import android.view.Gravity;
	import android.view.LayoutInflater;
	import android.view.View;
	import android.view.ViewDebug;

	import com.android.launcher3.BubbleTextView;
	import com.android.launcher3.CellLayout;
	import com.android.launcher3.DeviceProfile;
	import com.android.launcher3.InvariantDeviceProfile;
	import com.android.launcher3.ItemInfo;
	import com.android.launcher3.Launcher;
	import com.android.launcher3.LauncherAppState;
	import com.android.launcher3.PagedView;
	import com.android.launcher3.R;
	import com.android.launcher3.ShortcutAndWidgetContainer;
	import com.android.launcher3.WorkspaceItemInfo;
	import com.android.launcher3.Utilities;
	import com.android.launcher3.Workspace.ItemOperator;
	import com.android.launcher3.anim.Interpolators;
	import com.android.launcher3.keyboard.ViewGroupFocusHelper;
	import com.android.launcher3.pageindicators.PageIndicatorDots;
	import com.android.launcher3.touch.ItemClickHandler;
	import com.android.launcher3.util.Thunk;

	import java.util.ArrayList;
	import java.util.Iterator;
	import java.util.Map;

	public class FolderPagedView extends PagedView<PageIndicatorDots> {

	private static final String TAG = "FolderPagedView";

	private static final int REORDER_ANIMATION_DURATION = 230;
	private static final int START_VIEW_REORDER_DELAY = 30;
	private static final float VIEW_REORDER_DELAY_FACTOR = 0.9f;

	/**
	* Fraction of the width to scroll when showing the next page hint.
	*/
	private static final float SCROLL_HINT_FRACTION = 0.07f;

	private static final int[] sTmpArray = new int[2];

	public final boolean mIsRtl;

	private final LayoutInflater mInflater;
	private final ViewGroupFocusHelper mFocusIndicatorHelper;

	@Thunk final ArrayMap<View, Runnable> mPendingAnimations = new ArrayMap<>();

	@ViewDebug.ExportedProperty(category = "launcher")
	private final int mMaxCountX;
	@ViewDebug.ExportedProperty(category = "launcher")
	private final int mMaxCountY;
	@ViewDebug.ExportedProperty(category = "launcher")
	private final int mMaxItemsPerPage;

	private int mAllocatedContentSize;
	@ViewDebug.ExportedProperty(category = "launcher")
	private int mGridCountX;
	@ViewDebug.ExportedProperty(category = "launcher")
	private int mGridCountY;

	private Folder mFolder;

	public FolderPagedView(Context context, AttributeSet attrs) {
	super(context, attrs);
	InvariantDeviceProfile profile = LauncherAppState.getIDP(context);
	mMaxCountX = profile.numFolderColumns;
	mMaxCountY = profile.numFolderRows;

	mMaxItemsPerPage = mMaxCountX * mMaxCountY;

	mInflater = LayoutInflater.from(context);

	mIsRtl = Utilities.isRtl(getResources());
	setImportantForAccessibility(IMPORTANT_FOR_ACCESSIBILITY_YES);

	mFocusIndicatorHelper = new ViewGroupFocusHelper(this);
	}

	public void setFolder(Folder folder) {
	mFolder = folder;
	mPageIndicator = folder.findViewById(R.id.folder_page_indicator);
	initParentViews(folder);
	}

	/**
	* Calculates the grid size such that {@param count} items can fit in the grid.
	* The grid size is calculated such that countY <= countX and countX = ceil(sqrt(count)) while
	* maintaining the restrictions of {@link #mMaxCountX} & {@link #mMaxCountY}.
	*/
	public static void calculateGridSize(int count, int countX, int countY, int maxCountX,
	int maxCountY, int maxItemsPerPage, int[] out) {
	boolean done;
	int gridCountX = countX;
	int gridCountY = countY;

	if (count >= maxItemsPerPage) {
	gridCountX = maxCountX;
	gridCountY = maxCountY;
	done = true;
	} else {
	done = false;
	}

	while (!done) {
	int oldCountX = gridCountX;
	int oldCountY = gridCountY;
	if (gridCountX * gridCountY < count) {
	// Current grid is too small, expand it
	if ((gridCountX <= gridCountY \|\| gridCountY == maxCountY)
	&& gridCountX < maxCountX) {
	gridCountX++;
	} else if (gridCountY < maxCountY) {
	gridCountY++;
	}
	if (gridCountY == 0) gridCountY++;
	} else if ((gridCountY - 1) * gridCountX >= count && gridCountY >= gridCountX) {
	gridCountY = Math.max(0, gridCountY - 1);
	} else if ((gridCountX - 1) * gridCountY >= count) {
	gridCountX = Math.max(0, gridCountX - 1);
	}
	done = gridCountX == oldCountX && gridCountY == oldCountY;
	}

	out[0] = gridCountX;
	out[1] = gridCountY;
	}

	/**
	* Sets up the grid size such that {@param count} items can fit in the grid.
	*/
	public void setupContentDimensions(int count) {
	mAllocatedContentSize = count;
	calculateGridSize(count, mGridCountX, mGridCountY, mMaxCountX, mMaxCountY, mMaxItemsPerPage,
	sTmpArray);
	mGridCountX = sTmpArray[0];
	mGridCountY = sTmpArray[1];

	// Update grid size
	for (int i = getPageCount() - 1; i >= 0; i--) {
	getPageAt(i).setGridSize(mGridCountX, mGridCountY);
	}
	}

	@Override
	protected void dispatchDraw(Canvas canvas) {
	mFocusIndicatorHelper.draw(canvas);
	super.dispatchDraw(canvas);
	}

	/**
	* Binds items to the layout.
	*/
	public void bindItems(ArrayList<WorkspaceItemInfo> items) {
	ArrayList<View> icons = new ArrayList<>();
	for (WorkspaceItemInfo item : items) {
	icons.add(createNewView(item));
	}
	arrangeChildren(icons, icons.size(), false);
	}

	public void allocateSpaceForRank(int rank) {
	ArrayList<View> views = new ArrayList<>(mFolder.getItemsInReadingOrder());
	views.add(rank, null);
	arrangeChildren(views, views.size(), false);
	}

	/**
	* Create space for a new item at the end, and returns the rank for that item.
	* Also sets the current page to the last page.
	*/
	public int allocateRankForNewItem() {
	int rank = getItemCount();
	allocateSpaceForRank(rank);
	setCurrentPage(rank / mMaxItemsPerPage);
	return rank;
	}

	public View createAndAddViewForRank(WorkspaceItemInfo item, int rank) {
	View icon = createNewView(item);
	allocateSpaceForRank(rank);
	addViewForRank(icon, item, rank);
	return icon;
	}

	/**
	* Adds the {@param view} to the layout based on {@param rank} and updated the position
	* related attributes. It assumes that {@param item} is already attached to the view.
	*/
	public void addViewForRank(View view, WorkspaceItemInfo item, int rank) {
	int pagePos = rank % mMaxItemsPerPage;
	int pageNo = rank / mMaxItemsPerPage;

	item.rank = rank;
	item.cellX = pagePos % mGridCountX;
	item.cellY = pagePos / mGridCountX;

	CellLayout.LayoutParams lp = (CellLayout.LayoutParams) view.getLayoutParams();
	lp.cellX = item.cellX;
	lp.cellY = item.cellY;
	getPageAt(pageNo).addViewToCellLayout(view, -1, item.getViewId(), lp, true);
	}

	@SuppressLint("InflateParams")
	public View createNewView(WorkspaceItemInfo item) {
	final BubbleTextView textView = (BubbleTextView) mInflater.inflate(
	R.layout.folder_application, null, false);
	textView.applyFromWorkspaceItem(item);
	textView.setHapticFeedbackEnabled(false);
	textView.setOnClickListener(ItemClickHandler.INSTANCE);
	textView.setOnLongClickListener(mFolder);
	textView.setOnFocusChangeListener(mFocusIndicatorHelper);

	textView.setLayoutParams(new CellLayout.LayoutParams(
	item.cellX, item.cellY, item.spanX, item.spanY));
	return textView;
	}

	@Override
	public CellLayout getPageAt(int index) {
	return (CellLayout) getChildAt(index);
	}

	public CellLayout getCurrentCellLayout() {
	return getPageAt(getNextPage());
	}

	private CellLayout createAndAddNewPage() {
	DeviceProfile grid = Launcher.getLauncher(getContext()).getDeviceProfile();
	CellLayout page = (CellLayout) mInflater.inflate(R.layout.folder_page, this, false);
	page.setCellDimensions(grid.folderCellWidthPx, grid.folderCellHeightPx);
	page.getShortcutsAndWidgets().setMotionEventSplittingEnabled(false);
	page.setInvertIfRtl(true);
	page.setGridSize(mGridCountX, mGridCountY);

	addView(page, -1, generateDefaultLayoutParams());
	return page;
	}

	@Override
	protected int getChildGap() {
	return getPaddingLeft() + getPaddingRight();
	}

	public void setFixedSize(int width, int height) {
	width -= (getPaddingLeft() + getPaddingRight());
	height -= (getPaddingTop() + getPaddingBottom());
	for (int i = getChildCount() - 1; i >= 0; i --) {
	((CellLayout) getChildAt(i)).setFixedSize(width, height);
	}
	}

	public void removeItem(View v) {
	for (int i = getChildCount() - 1; i >= 0; i --) {
	getPageAt(i).removeView(v);
	}
	}

	@Override
	protected void onScrollChanged(int l, int t, int oldl, int oldt) {
	super.onScrollChanged(l, t, oldl, oldt);
	mPageIndicator.setScroll(l, mMaxScrollX);
	}

	/**
	* Updates position and rank of all the children in the view.
	* It essentially removes all views from all the pages and then adds them again in appropriate
	* page.
	*
	* @param list the ordered list of children.
	* @param itemCount if greater than the total children count, empty spaces are left
	* at the end, otherwise it is ignored.
	*
	*/
	public void arrangeChildren(ArrayList<View> list, int itemCount) {
	arrangeChildren(list, itemCount, true);
	}

	@SuppressLint("RtlHardcoded")
	private void arrangeChildren(ArrayList<View> list, int itemCount, boolean saveChanges) {
	ArrayList<CellLayout> pages = new ArrayList<>();
	for (int i = 0; i < getChildCount(); i++) {
	CellLayout page = (CellLayout) getChildAt(i);
	page.removeAllViews();
	pages.add(page);
	}
	setupContentDimensions(itemCount);

	Iterator<CellLayout> pageItr = pages.iterator();
	CellLayout currentPage = null;

	int position = 0;
	int newX, newY, rank;

	FolderIconPreviewVerifier verifier = new FolderIconPreviewVerifier(
	Launcher.getLauncher(getContext()).getDeviceProfile().inv);
	verifier.setFolderInfo(mFolder.getInfo());
	rank = 0;
	for (int i = 0; i < itemCount; i++) {
	View v = list.size() > i ? list.get(i) : null;
	if (currentPage == null \|\| position >= mMaxItemsPerPage) {
	// Next page
	if (pageItr.hasNext()) {
	currentPage = pageItr.next();
	} else {
	currentPage = createAndAddNewPage();
	}
	position = 0;
	}

	if (v != null) {
	CellLayout.LayoutParams lp = (CellLayout.LayoutParams) v.getLayoutParams();
	newX = position % mGridCountX;
	newY = position / mGridCountX;
	ItemInfo info = (ItemInfo) v.getTag();
	if (info.cellX != newX \|\| info.cellY != newY \|\| info.rank != rank) {
	info.cellX = newX;
	info.cellY = newY;
	info.rank = rank;
	if (saveChanges) {
	mFolder.mLauncher.getModelWriter().addOrMoveItemInDatabase(info,
	mFolder.mInfo.id, 0, info.cellX, info.cellY);
	}
	}
	lp.cellX = info.cellX;
	lp.cellY = info.cellY;
	currentPage.addViewToCellLayout(v, -1, info.getViewId(), lp, true);

	if (verifier.isItemInPreview(rank) && v instanceof BubbleTextView) {
	((BubbleTextView) v).verifyHighRes();
	}
	}

	rank ++;
	position++;
	}

	// Remove extra views.
	boolean removed = false;
	while (pageItr.hasNext()) {
	removeView(pageItr.next());
	removed = true;
	}
	if (removed) {
	setCurrentPage(0);
	}

	setEnableOverscroll(getPageCount() > 1);

	// Update footer
	mPageIndicator.setVisibility(getPageCount() > 1 ? View.VISIBLE : View.GONE);
	// Set the gravity as LEFT or RIGHT instead of START, as START depends on the actual text.
	mFolder.mFolderName.setGravity(getPageCount() > 1 ?
	(mIsRtl ? Gravity.RIGHT : Gravity.LEFT) : Gravity.CENTER_HORIZONTAL);
	}

	public int getDesiredWidth() {
	return getPageCount() > 0 ?
	(getPageAt(0).getDesiredWidth() + getPaddingLeft() + getPaddingRight()) : 0;
	}

	public int getDesiredHeight() {
	return getPageCount() > 0 ?
	(getPageAt(0).getDesiredHeight() + getPaddingTop() + getPaddingBottom()) : 0;
	}

	public int getItemCount() {
	int lastPageIndex = getChildCount() - 1;
	if (lastPageIndex < 0) {
	// If there are no pages, nothing has yet been added to the folder.
	return 0;
	}
	return getPageAt(lastPageIndex).getShortcutsAndWidgets().getChildCount()
	+ lastPageIndex * mMaxItemsPerPage;
	}

	/**
	* @return the rank of the cell nearest to the provided pixel position.
	*/
	public int findNearestArea(int pixelX, int pixelY) {
	int pageIndex = getNextPage();
	CellLayout page = getPageAt(pageIndex);
	page.findNearestArea(pixelX, pixelY, 1, 1, sTmpArray);
	if (mFolder.isLayoutRtl()) {
	sTmpArray[0] = page.getCountX() - sTmpArray[0] - 1;
	}
	return Math.min(mAllocatedContentSize - 1,
	pageIndex * mMaxItemsPerPage + sTmpArray[1] * mGridCountX + sTmpArray[0]);
	}

	public View getFirstItem() {
	if (getChildCount() < 1) {
	return null;
	}
	ShortcutAndWidgetContainer currContainer = getCurrentCellLayout().getShortcutsAndWidgets();
	if (mGridCountX > 0) {
	return currContainer.getChildAt(0, 0);
	} else {
	return currContainer.getChildAt(0);
	}
	}

	public View getLastItem() {
	if (getChildCount() < 1) {
	return null;
	}
	ShortcutAndWidgetContainer currContainer = getCurrentCellLayout().getShortcutsAndWidgets();
	int lastRank = currContainer.getChildCount() - 1;
	if (mGridCountX > 0) {
	return currContainer.getChildAt(lastRank % mGridCountX, lastRank / mGridCountX);
	} else {
	return currContainer.getChildAt(lastRank);
	}
	}

	/**
	* Iterates over all its items in a reading order.
	* @return the view for which the operator returned true.
	*/
	public View iterateOverItems(ItemOperator op) {
	for (int k = 0 ; k < getChildCount(); k++) {
	CellLayout page = getPageAt(k);
	for (int j = 0; j < page.getCountY(); j++) {
	for (int i = 0; i < page.getCountX(); i++) {
	View v = page.getChildAt(i, j);
	if ((v != null) && op.evaluate((ItemInfo) v.getTag(), v)) {
	return v;
	}
	}
	}
	}
	return null;
	}

	public String getAccessibilityDescription() {
	return getContext().getString(R.string.folder_opened, mGridCountX, mGridCountY);
	}

	/**
	* Sets the focus on the first visible child.
	*/
	public void setFocusOnFirstChild() {
	View firstChild = getCurrentCellLayout().getChildAt(0, 0);
	if (firstChild != null) {
	firstChild.requestFocus();
	}
	}

	@Override
	protected void notifyPageSwitchListener(int prevPage) {
	super.notifyPageSwitchListener(prevPage);
	if (mFolder != null) {
	mFolder.updateTextViewFocus();
	}
	}

	/**
	* Scrolls the current view by a fraction
	*/
	public void showScrollHint(int direction) {
	float fraction = (direction == Folder.SCROLL_LEFT) ^ mIsRtl
	? -SCROLL_HINT_FRACTION : SCROLL_HINT_FRACTION;
	int hint = (int) (fraction * getWidth());
	int scroll = getScrollForPage(getNextPage()) + hint;
	int delta = scroll - getScrollX();
	if (delta != 0) {
	mScroller.setInterpolator(Interpolators.DEACCEL);
	mScroller.startScroll(getScrollX(), delta, Folder.SCROLL_HINT_DURATION);
	invalidate();
	}
	}

	public void clearScrollHint() {
	if (getScrollX() != getScrollForPage(getNextPage())) {
	snapToPage(getNextPage());
	}
	}

	/**
	* Finish animation all the views which are animating across pages
	*/
	public void completePendingPageChanges() {
	if (!mPendingAnimations.isEmpty()) {
	ArrayMap<View, Runnable> pendingViews = new ArrayMap<>(mPendingAnimations);
	for (Map.Entry<View, Runnable> e : pendingViews.entrySet()) {
	e.getKey().animate().cancel();
	e.getValue().run();
	}
	}
	}

	public boolean rankOnCurrentPage(int rank) {
	int p = rank / mMaxItemsPerPage;
	return p == getNextPage();
	}

	@Override
	protected void onPageBeginTransition() {
	super.onPageBeginTransition();
	// Ensure that adjacent pages have high resolution icons
	verifyVisibleHighResIcons(getCurrentPage() - 1);
	verifyVisibleHighResIcons(getCurrentPage() + 1);
	}

	/**
	* Ensures that all the icons on the given page are of high-res
	*/
	public void verifyVisibleHighResIcons(int pageNo) {
	CellLayout page = getPageAt(pageNo);
	if (page != null) {
	ShortcutAndWidgetContainer parent = page.getShortcutsAndWidgets();
	for (int i = parent.getChildCount() - 1; i >= 0; i--) {
	BubbleTextView icon = ((BubbleTextView) parent.getChildAt(i));
	icon.verifyHighRes();
	// Set the callback back to the actual icon, in case
	// it was captured by the FolderIcon
	Drawable d = icon.getCompoundDrawables()[1];
	if (d != null) {
	d.setCallback(icon);
	}
	}
	}
	}

	public int getAllocatedContentSize() {
	return mAllocatedContentSize;
	}

	/**
	* Reorders the items such that the {@param empty} spot moves to {@param target}
	*/
	public void realTimeReorder(int empty, int target) {
	completePendingPageChanges();
	int delay = 0;
	float delayAmount = START_VIEW_REORDER_DELAY;

	// Animation only happens on the current page.
	int pageToAnimate = getNextPage();

	int pageT = target / mMaxItemsPerPage;
	int pagePosT = target % mMaxItemsPerPage;

	if (pageT != pageToAnimate) {
	Log.e(TAG, "Cannot animate when the target cell is invisible");
	}
	int pagePosE = empty % mMaxItemsPerPage;
	int pageE = empty / mMaxItemsPerPage;

	int startPos, endPos;
	int moveStart, moveEnd;
	int direction;

	if (target == empty) {
	// No animation
	return;
	} else if (target > empty) {
	// Items will move backwards to make room for the empty cell.
	direction = 1;

	// If empty cell is in a different page, move them instantly.
	if (pageE < pageToAnimate) {
	moveStart = empty;
	// Instantly move the first item in the current page.
	moveEnd = pageToAnimate * mMaxItemsPerPage;
	// Animate the 2nd item in the current page, as the first item was already moved to
	// the last page.
	startPos = 0;
	} else {
	moveStart = moveEnd = -1;
	startPos = pagePosE;
	}

	endPos = pagePosT;
	} else {
	// The items will move forward.
	direction = -1;

	if (pageE > pageToAnimate) {
	// Move the items immediately.
	moveStart = empty;
	// Instantly move the last item in the current page.
	moveEnd = (pageToAnimate + 1) * mMaxItemsPerPage - 1;

	// Animations start with the second last item in the page
	startPos = mMaxItemsPerPage - 1;
	} else {
	moveStart = moveEnd = -1;
	startPos = pagePosE;
	}

	endPos = pagePosT;
	}

	// Instant moving views.
	while (moveStart != moveEnd) {
	int rankToMove = moveStart + direction;
	int p = rankToMove / mMaxItemsPerPage;
	int pagePos = rankToMove % mMaxItemsPerPage;
	int x = pagePos % mGridCountX;
	int y = pagePos / mGridCountX;

	final CellLayout page = getPageAt(p);
	final View v = page.getChildAt(x, y);
	if (v != null) {
	if (pageToAnimate != p) {
	page.removeView(v);
	addViewForRank(v, (WorkspaceItemInfo) v.getTag(), moveStart);
	} else {
	// Do a fake animation before removing it.
	final int newRank = moveStart;
	final float oldTranslateX = v.getTranslationX();

	Runnable endAction = new Runnable() {

	@Override
	public void run() {
	mPendingAnimations.remove(v);
	v.setTranslationX(oldTranslateX);
	((CellLayout) v.getParent().getParent()).removeView(v);
	addViewForRank(v, (WorkspaceItemInfo) v.getTag(), newRank);
	}
	};
	v.animate()
	.translationXBy((direction > 0 ^ mIsRtl) ? -v.getWidth() : v.getWidth())
	.setDuration(REORDER_ANIMATION_DURATION)
	.setStartDelay(0)
	.withEndAction(endAction);
	mPendingAnimations.put(v, endAction);
	}
	}
	moveStart = rankToMove;
	}

	if ((endPos - startPos) * direction <= 0) {
	// No animation
	return;
	}

	CellLayout page = getPageAt(pageToAnimate);
	for (int i = startPos; i != endPos; i += direction) {
	int nextPos = i + direction;
	View v = page.getChildAt(nextPos % mGridCountX, nextPos / mGridCountX);
	if (v != null) {
	((ItemInfo) v.getTag()).rank -= direction;
	}
	if (page.animateChildToPosition(v, i % mGridCountX, i / mGridCountX,
	REORDER_ANIMATION_DURATION, delay, true, true)) {
	delay += delayAmount;
	delayAmount *= VIEW_REORDER_DELAY_FACTOR;
	}
	}
	}

	public int itemsPerPage() {
	return mMaxItemsPerPage;
	}
	}