src/com/android/launcher2/FolderIcon.java - fp2-dev/platform/packages/apps/Launcher3 - 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.launcher2;

 import java.util.ArrayList;

 import android.animation.Animator;
 import android.animation.AnimatorListenerAdapter;
 import android.animation.ValueAnimator;
 import android.animation.ValueAnimator.AnimatorUpdateListener;
 import android.content.Context;
 import android.content.res.Resources;
 import android.graphics.Canvas;
 import android.graphics.Color;
 import android.graphics.PorterDuff;
 import android.graphics.drawable.Drawable;
 import android.util.AttributeSet;
 import android.view.LayoutInflater;
 import android.view.View;
 import android.view.ViewGroup;
 import android.widget.FrameLayout;
 import android.widget.TextView;

 import com.android.launcher.R;
 import com.android.launcher2.FolderInfo.FolderListener;

 /**
  * An icon that can appear on in the workspace representing an {@link UserFolder}.
  */
 public class FolderIcon extends FrameLayout implements DropTarget, FolderListener {
     private Launcher mLauncher;
     Folder mFolder;
     FolderInfo mInfo;

     // The number of icons to display in the
     private static final int NUM_ITEMS_IN_PREVIEW = 4;
     private static final int CONSUMPTION_ANIMATION_DURATION = 100;

     // The degree to which the inner ring grows when accepting drop
     private static final float INNER_RING_GROWTH_FACTOR = 0.1f;

     // The degree to which the inner ring is scaled in its natural state
     private static final float INNER_RING_BASELINE_SCALE = 1.0f;

     // The degree to which the outer ring grows when accepting drop
     private static final float OUTER_RING_BASELINE_SCALE = 0.7f;

     // The degree to which the outer ring is scaled in its natural state
     private static final float OUTER_RING_GROWTH_FACTOR = 0.3f;

     // The amount of vertical spread between items in the stack [0...1]
     private static final float PERSPECTIVE_SHIFT_FACTOR = 0.18f;

     // The degree to which the item in the back of the stack is scaled [0...1]
     // (0 means it's not scaled at all, 1 means it's scaled to nothing)
     private static final float PERSPECTIVE_SCALE_FACTOR = 0.3f;

     // The percentage of the FolderIcons view that will be dedicated to the items preview
     private static final float SPACE_PERCENTAGE_FOR_ICONS = 0.8f;

     public static Drawable sFolderOuterRingDrawable = null;
     public static Drawable sFolderInnerRingDrawable = null;

     private int mOriginalWidth = -1;
     private int mOriginalHeight = -1;

     FolderRingAnimator mFolderRingAnimator = null;

     public FolderIcon(Context context, AttributeSet attrs) {
         super(context, attrs);
     }

     public FolderIcon(Context context) {
         super(context);
     }

     public boolean isDropEnabled() {
         final ViewGroup cellLayoutChildren = (ViewGroup) getParent();
         final ViewGroup cellLayout = (ViewGroup) cellLayoutChildren.getParent();
         final Workspace workspace = (Workspace) cellLayout.getParent();
         return !workspace.isSmall();
     }

     static FolderIcon fromXml(int resId, Launcher launcher, ViewGroup group,
             FolderInfo folderInfo, IconCache iconCache) {

         FolderIcon icon = (FolderIcon) LayoutInflater.from(launcher).inflate(resId, group, false);

         final Resources resources = launcher.getResources();
         Drawable d = iconCache.getFullResIcon(resources, R.drawable.portal_ring_inner_holo);
         icon.setBackgroundDrawable(d);
         icon.setTag(folderInfo);
         icon.setOnClickListener(launcher);
         icon.mInfo = folderInfo;
         icon.mLauncher = launcher;

         Folder folder = Folder.fromXml(launcher);
         folder.setDragController(launcher.getDragController());
         folder.setLauncher(launcher);
         folder.setFolderIcon(icon);
         folder.bind(folderInfo);
         icon.mFolder = folder;
         icon.mFolderRingAnimator = new FolderRingAnimator(launcher, icon);
         folderInfo.addListener(icon);

         return icon;
     }

     public static class FolderRingAnimator {
         public int mFolderLocX;
         public int mFolderLocY;
         public float mOuterRingScale;
         public float mInnerRingScale;
         public FolderIcon mFolderIcon = null;
         private Launcher mLauncher;

         public FolderRingAnimator(Launcher launcher, FolderIcon folderIcon) {
             mLauncher = launcher;
             mFolderIcon = folderIcon;
             if (sFolderOuterRingDrawable == null) {
                 sFolderOuterRingDrawable =
                         launcher.getResources().getDrawable(R.drawable.portal_ring_outer_holo);
             }
             if (sFolderInnerRingDrawable == null) {
                 sFolderInnerRingDrawable =
                         launcher.getResources().getDrawable(R.drawable.portal_ring_inner_holo);
             }
         }

         public void setLocation(int x, int y) {
             mFolderLocX = x;
             mFolderLocY = y;
         }

         public void animateToAcceptState() {
             ValueAnimator va = ValueAnimator.ofFloat(0f, 1f);
             va.setDuration(CONSUMPTION_ANIMATION_DURATION);
             va.addUpdateListener(new AnimatorUpdateListener() {
                 public void onAnimationUpdate(ValueAnimator animation) {
                     final float percent = (Float) animation.getAnimatedValue();
                     mOuterRingScale = OUTER_RING_BASELINE_SCALE + percent * OUTER_RING_GROWTH_FACTOR;
                     mInnerRingScale = INNER_RING_BASELINE_SCALE + percent * INNER_RING_GROWTH_FACTOR;
                     mLauncher.getWorkspace().invalidate();
                     if (mFolderIcon != null) {
                         mFolderIcon.invalidate();
                     }
                 }
             });
             va.addListener(new AnimatorListenerAdapter() {
                 @Override
                 public void onAnimationEnd(Animator animation) {
                     // Instead of setting the background drawable to null, we set the color to
                     // transparent. Setting the background drawable to null results in onDraw
                     // not getting called.
                     if (mFolderIcon != null) {
                         mFolderIcon.setBackgroundColor(Color.TRANSPARENT);
                         mFolderIcon.requestLayout();
                     }
                 }
             });
             va.start();
         }

         public void animateToNaturalState() {
             ValueAnimator va = ValueAnimator.ofFloat(0f, 1f);
             va.setDuration(CONSUMPTION_ANIMATION_DURATION);
             va.addUpdateListener(new AnimatorUpdateListener() {
                 public void onAnimationUpdate(ValueAnimator animation) {
                     final float percent = (Float) animation.getAnimatedValue();
                     mOuterRingScale = OUTER_RING_BASELINE_SCALE + OUTER_RING_GROWTH_FACTOR
                             - percent * OUTER_RING_GROWTH_FACTOR;
                     mInnerRingScale = INNER_RING_BASELINE_SCALE + INNER_RING_GROWTH_FACTOR
                             - percent * INNER_RING_GROWTH_FACTOR;
                     mLauncher.getWorkspace().invalidate();
                     if (mFolderIcon != null) {
                         mFolderIcon.invalidate();
                     }
                 }
             });
             va.addListener(new AnimatorListenerAdapter() {
                 @Override
                 public void onAnimationEnd(Animator animation) {
                     if (mFolderIcon != null) {
                         mFolderIcon.setBackgroundDrawable(sFolderInnerRingDrawable);
                     }
                     mLauncher.getWorkspace().hideFolderAccept(FolderRingAnimator.this);
                 }
             });
             va.start();
         }

         public void getLocation(int[] loc) {
             loc[0] = mFolderLocX;
             loc[1] = mFolderLocY;
         }

         public float getOuterRingScale() {
             return mOuterRingScale;
         }

         public float getInnerRingScale() {
             return mInnerRingScale;
         }
     }

     private boolean willAcceptItem(ItemInfo item) {
         final int itemType = item.itemType;
         return ((itemType == LauncherSettings.Favorites.ITEM_TYPE_APPLICATION ||
                 itemType == LauncherSettings.Favorites.ITEM_TYPE_SHORTCUT) &&
                 !mFolder.isFull() && item != mInfo);
     }

     public boolean acceptDrop(DragObject d) {
         final ItemInfo item = (ItemInfo) d.dragInfo;
         return willAcceptItem(item);
     }

     public void addItem(ShortcutInfo item) {
         mInfo.add(item);
         LauncherModel.addOrMoveItemInDatabase(mLauncher, item, mInfo.id, 0, item.cellX, item.cellY);
     }

     public void onDrop(DragObject d) {
         ShortcutInfo item;
         if (d.dragInfo instanceof ApplicationInfo) {
             // Came from all apps -- make a copy
             item = ((ApplicationInfo) d.dragInfo).makeShortcut();
         } else {
             item = (ShortcutInfo) d.dragInfo;
         }
         item.cellX = -1;
         item.cellY = -1;
         addItem(item);
     }

     void saveState(CellLayout.LayoutParams lp) {
         mOriginalWidth = lp.width;
         mOriginalHeight = lp.height;
     }

     private void determineFolderLocationInWorkspace() {
         int tvLocation[] = new int[2];
         int wsLocation[] = new int[2];
         getLocationOnScreen(tvLocation);
         mLauncher.getWorkspace().getLocationOnScreen(wsLocation);

         int x = tvLocation[0] - wsLocation[0] + getMeasuredWidth() / 2;
         int y = tvLocation[1] - wsLocation[1] + getMeasuredHeight() / 2;
         mFolderRingAnimator.setLocation(x, y);
     }

     public void onDragEnter(DragObject d) {
         if (!willAcceptItem((ItemInfo) d.dragInfo)) return;
         determineFolderLocationInWorkspace();
         mLauncher.getWorkspace().showFolderAccept(mFolderRingAnimator);
         mFolderRingAnimator.animateToAcceptState();
     }

     public void onDragOver(DragObject d) {
     }

     public void onDragExit(DragObject d) {
         if (!willAcceptItem((ItemInfo) d.dragInfo)) return;
         mFolderRingAnimator.animateToNaturalState();
     }

     public DropTarget getDropTargetDelegate(DragObject d) {
         return null;
     }

     @Override
     protected void onDraw(Canvas canvas) {
         if (mFolder == null) return;
         if (mFolder.getItemCount() == 0) return;

         canvas.save();
         TextView v = (TextView) mFolder.getItemAt(0);
         Drawable d = v.getCompoundDrawables()[1];

         if (mOriginalWidth < 0 || mOriginalHeight < 0) {
             mOriginalWidth = getMeasuredWidth();
             mOriginalHeight = getMeasuredHeight();
         }

         int unscaledHeight = (int) (d.getIntrinsicHeight() * (1 + PERSPECTIVE_SHIFT_FACTOR));
         float baselineIconScale = SPACE_PERCENTAGE_FOR_ICONS / (unscaledHeight / (mOriginalHeight * 1.0f));

         int baselineHeight = (int) (d.getIntrinsicHeight() * baselineIconScale);
         int totalStackHeight = (int) (baselineHeight * (1 + PERSPECTIVE_SHIFT_FACTOR));
         int baselineWidth = (int) (d.getIntrinsicWidth() * baselineIconScale);
         float maxPerpectiveShift = baselineHeight * PERSPECTIVE_SHIFT_FACTOR;

         ArrayList<View> items = mFolder.getItemsInReadingOrder();
         int firstItemIndex = Math.max(0, items.size() - NUM_ITEMS_IN_PREVIEW);

         int xShift = (int) (mOriginalWidth - baselineWidth) / 2;
         int yShift = (int) (mOriginalHeight - totalStackHeight) / 2;
         canvas.translate(xShift, yShift);
         for (int i = firstItemIndex; i < items.size(); i++) {
             int index = i - firstItemIndex;
             index += Math.max(0, NUM_ITEMS_IN_PREVIEW - items.size());

             float r = (index * 1.0f) / (NUM_ITEMS_IN_PREVIEW - 1);
             float scale = (1 - PERSPECTIVE_SCALE_FACTOR * (1 - r));
             r = (float) Math.pow(r, 2);

             float transY = r * maxPerpectiveShift;
             float transX = (1 - scale) * baselineWidth / 2.0f;

             v = (TextView) items.get(i);
             d = v.getCompoundDrawables()[1];

             canvas.save();
             canvas.translate(transX, transY);
             canvas.scale(baselineIconScale * scale, baselineIconScale * scale);

             int overlayAlpha = (int) (80 * (1 - r));
             if (d != null) {
                 d.setBounds(0, 0, d.getIntrinsicWidth(), d.getIntrinsicHeight());
                 d.setColorFilter(Color.argb(overlayAlpha, 0, 0, 0), PorterDuff.Mode.SRC_ATOP);
                 d.draw(canvas);
                 d.clearColorFilter();
             }
             canvas.restore();
         }

         canvas.restore();
     }

     public void onAdd(ShortcutInfo item) {
         invalidate();
         requestLayout();
     }

     public void onRemove(ShortcutInfo item) {
         invalidate();
         requestLayout();
     }
 }
	/*
	* 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.launcher2;

	import java.util.ArrayList;

	import android.animation.Animator;
	import android.animation.AnimatorListenerAdapter;
	import android.animation.ValueAnimator;
	import android.animation.ValueAnimator.AnimatorUpdateListener;
	import android.content.Context;
	import android.content.res.Resources;
	import android.graphics.Canvas;
	import android.graphics.Color;
	import android.graphics.PorterDuff;
	import android.graphics.drawable.Drawable;
	import android.util.AttributeSet;
	import android.view.LayoutInflater;
	import android.view.View;
	import android.view.ViewGroup;
	import android.widget.FrameLayout;
	import android.widget.TextView;

	import com.android.launcher.R;
	import com.android.launcher2.FolderInfo.FolderListener;

	/**
	* An icon that can appear on in the workspace representing an {@link UserFolder}.
	*/
	public class FolderIcon extends FrameLayout implements DropTarget, FolderListener {
	private Launcher mLauncher;
	Folder mFolder;
	FolderInfo mInfo;

	// The number of icons to display in the
	private static final int NUM_ITEMS_IN_PREVIEW = 4;
	private static final int CONSUMPTION_ANIMATION_DURATION = 100;

	// The degree to which the inner ring grows when accepting drop
	private static final float INNER_RING_GROWTH_FACTOR = 0.1f;

	// The degree to which the inner ring is scaled in its natural state
	private static final float INNER_RING_BASELINE_SCALE = 1.0f;

	// The degree to which the outer ring grows when accepting drop
	private static final float OUTER_RING_BASELINE_SCALE = 0.7f;

	// The degree to which the outer ring is scaled in its natural state
	private static final float OUTER_RING_GROWTH_FACTOR = 0.3f;

	// The amount of vertical spread between items in the stack [0...1]
	private static final float PERSPECTIVE_SHIFT_FACTOR = 0.18f;

	// The degree to which the item in the back of the stack is scaled [0...1]
	// (0 means it's not scaled at all, 1 means it's scaled to nothing)
	private static final float PERSPECTIVE_SCALE_FACTOR = 0.3f;

	// The percentage of the FolderIcons view that will be dedicated to the items preview
	private static final float SPACE_PERCENTAGE_FOR_ICONS = 0.8f;

	public static Drawable sFolderOuterRingDrawable = null;
	public static Drawable sFolderInnerRingDrawable = null;

	private int mOriginalWidth = -1;
	private int mOriginalHeight = -1;

	FolderRingAnimator mFolderRingAnimator = null;

	public FolderIcon(Context context, AttributeSet attrs) {
	super(context, attrs);
	}

	public FolderIcon(Context context) {
	super(context);
	}

	public boolean isDropEnabled() {
	final ViewGroup cellLayoutChildren = (ViewGroup) getParent();
	final ViewGroup cellLayout = (ViewGroup) cellLayoutChildren.getParent();
	final Workspace workspace = (Workspace) cellLayout.getParent();
	return !workspace.isSmall();
	}

	static FolderIcon fromXml(int resId, Launcher launcher, ViewGroup group,
	FolderInfo folderInfo, IconCache iconCache) {

	FolderIcon icon = (FolderIcon) LayoutInflater.from(launcher).inflate(resId, group, false);

	final Resources resources = launcher.getResources();
	Drawable d = iconCache.getFullResIcon(resources, R.drawable.portal_ring_inner_holo);
	icon.setBackgroundDrawable(d);
	icon.setTag(folderInfo);
	icon.setOnClickListener(launcher);
	icon.mInfo = folderInfo;
	icon.mLauncher = launcher;

	Folder folder = Folder.fromXml(launcher);
	folder.setDragController(launcher.getDragController());
	folder.setLauncher(launcher);
	folder.setFolderIcon(icon);
	folder.bind(folderInfo);
	icon.mFolder = folder;
	icon.mFolderRingAnimator = new FolderRingAnimator(launcher, icon);
	folderInfo.addListener(icon);

	return icon;
	}

	public static class FolderRingAnimator {
	public int mFolderLocX;
	public int mFolderLocY;
	public float mOuterRingScale;
	public float mInnerRingScale;
	public FolderIcon mFolderIcon = null;
	private Launcher mLauncher;

	public FolderRingAnimator(Launcher launcher, FolderIcon folderIcon) {
	mLauncher = launcher;
	mFolderIcon = folderIcon;
	if (sFolderOuterRingDrawable == null) {
	sFolderOuterRingDrawable =
	launcher.getResources().getDrawable(R.drawable.portal_ring_outer_holo);
	}
	if (sFolderInnerRingDrawable == null) {
	sFolderInnerRingDrawable =
	launcher.getResources().getDrawable(R.drawable.portal_ring_inner_holo);
	}
	}

	public void setLocation(int x, int y) {
	mFolderLocX = x;
	mFolderLocY = y;
	}

	public void animateToAcceptState() {
	ValueAnimator va = ValueAnimator.ofFloat(0f, 1f);
	va.setDuration(CONSUMPTION_ANIMATION_DURATION);
	va.addUpdateListener(new AnimatorUpdateListener() {
	public void onAnimationUpdate(ValueAnimator animation) {
	final float percent = (Float) animation.getAnimatedValue();
	mOuterRingScale = OUTER_RING_BASELINE_SCALE + percent * OUTER_RING_GROWTH_FACTOR;
	mInnerRingScale = INNER_RING_BASELINE_SCALE + percent * INNER_RING_GROWTH_FACTOR;
	mLauncher.getWorkspace().invalidate();
	if (mFolderIcon != null) {
	mFolderIcon.invalidate();
	}
	}
	});
	va.addListener(new AnimatorListenerAdapter() {
	@Override
	public void onAnimationEnd(Animator animation) {
	// Instead of setting the background drawable to null, we set the color to
	// transparent. Setting the background drawable to null results in onDraw
	// not getting called.
	if (mFolderIcon != null) {
	mFolderIcon.setBackgroundColor(Color.TRANSPARENT);
	mFolderIcon.requestLayout();
	}
	}
	});
	va.start();
	}

	public void animateToNaturalState() {
	ValueAnimator va = ValueAnimator.ofFloat(0f, 1f);
	va.setDuration(CONSUMPTION_ANIMATION_DURATION);
	va.addUpdateListener(new AnimatorUpdateListener() {
	public void onAnimationUpdate(ValueAnimator animation) {
	final float percent = (Float) animation.getAnimatedValue();
	mOuterRingScale = OUTER_RING_BASELINE_SCALE + OUTER_RING_GROWTH_FACTOR
	- percent * OUTER_RING_GROWTH_FACTOR;
	mInnerRingScale = INNER_RING_BASELINE_SCALE + INNER_RING_GROWTH_FACTOR
	- percent * INNER_RING_GROWTH_FACTOR;
	mLauncher.getWorkspace().invalidate();
	if (mFolderIcon != null) {
	mFolderIcon.invalidate();
	}
	}
	});
	va.addListener(new AnimatorListenerAdapter() {
	@Override
	public void onAnimationEnd(Animator animation) {
	if (mFolderIcon != null) {
	mFolderIcon.setBackgroundDrawable(sFolderInnerRingDrawable);
	}
	mLauncher.getWorkspace().hideFolderAccept(FolderRingAnimator.this);
	}
	});
	va.start();
	}

	public void getLocation(int[] loc) {
	loc[0] = mFolderLocX;
	loc[1] = mFolderLocY;
	}

	public float getOuterRingScale() {
	return mOuterRingScale;
	}

	public float getInnerRingScale() {
	return mInnerRingScale;
	}
	}

	private boolean willAcceptItem(ItemInfo item) {
	final int itemType = item.itemType;
	return ((itemType == LauncherSettings.Favorites.ITEM_TYPE_APPLICATION \|\|
	itemType == LauncherSettings.Favorites.ITEM_TYPE_SHORTCUT) &&
	!mFolder.isFull() && item != mInfo);
	}

	public boolean acceptDrop(DragObject d) {
	final ItemInfo item = (ItemInfo) d.dragInfo;
	return willAcceptItem(item);
	}

	public void addItem(ShortcutInfo item) {
	mInfo.add(item);
	LauncherModel.addOrMoveItemInDatabase(mLauncher, item, mInfo.id, 0, item.cellX, item.cellY);
	}

	public void onDrop(DragObject d) {
	ShortcutInfo item;
	if (d.dragInfo instanceof ApplicationInfo) {
	// Came from all apps -- make a copy
	item = ((ApplicationInfo) d.dragInfo).makeShortcut();
	} else {
	item = (ShortcutInfo) d.dragInfo;
	}
	item.cellX = -1;
	item.cellY = -1;
	addItem(item);
	}

	void saveState(CellLayout.LayoutParams lp) {
	mOriginalWidth = lp.width;
	mOriginalHeight = lp.height;
	}

	private void determineFolderLocationInWorkspace() {
	int tvLocation[] = new int[2];
	int wsLocation[] = new int[2];
	getLocationOnScreen(tvLocation);
	mLauncher.getWorkspace().getLocationOnScreen(wsLocation);

	int x = tvLocation[0] - wsLocation[0] + getMeasuredWidth() / 2;
	int y = tvLocation[1] - wsLocation[1] + getMeasuredHeight() / 2;
	mFolderRingAnimator.setLocation(x, y);
	}

	public void onDragEnter(DragObject d) {
	if (!willAcceptItem((ItemInfo) d.dragInfo)) return;
	determineFolderLocationInWorkspace();
	mLauncher.getWorkspace().showFolderAccept(mFolderRingAnimator);
	mFolderRingAnimator.animateToAcceptState();
	}

	public void onDragOver(DragObject d) {
	}

	public void onDragExit(DragObject d) {
	if (!willAcceptItem((ItemInfo) d.dragInfo)) return;
	mFolderRingAnimator.animateToNaturalState();
	}

	public DropTarget getDropTargetDelegate(DragObject d) {
	return null;
	}

	@Override
	protected void onDraw(Canvas canvas) {
	if (mFolder == null) return;
	if (mFolder.getItemCount() == 0) return;

	canvas.save();
	TextView v = (TextView) mFolder.getItemAt(0);
	Drawable d = v.getCompoundDrawables()[1];

	if (mOriginalWidth < 0 \|\| mOriginalHeight < 0) {
	mOriginalWidth = getMeasuredWidth();
	mOriginalHeight = getMeasuredHeight();
	}

	int unscaledHeight = (int) (d.getIntrinsicHeight() * (1 + PERSPECTIVE_SHIFT_FACTOR));
	float baselineIconScale = SPACE_PERCENTAGE_FOR_ICONS / (unscaledHeight / (mOriginalHeight * 1.0f));

	int baselineHeight = (int) (d.getIntrinsicHeight() * baselineIconScale);
	int totalStackHeight = (int) (baselineHeight * (1 + PERSPECTIVE_SHIFT_FACTOR));
	int baselineWidth = (int) (d.getIntrinsicWidth() * baselineIconScale);
	float maxPerpectiveShift = baselineHeight * PERSPECTIVE_SHIFT_FACTOR;

	ArrayList<View> items = mFolder.getItemsInReadingOrder();
	int firstItemIndex = Math.max(0, items.size() - NUM_ITEMS_IN_PREVIEW);

	int xShift = (int) (mOriginalWidth - baselineWidth) / 2;
	int yShift = (int) (mOriginalHeight - totalStackHeight) / 2;
	canvas.translate(xShift, yShift);
	for (int i = firstItemIndex; i < items.size(); i++) {
	int index = i - firstItemIndex;
	index += Math.max(0, NUM_ITEMS_IN_PREVIEW - items.size());

	float r = (index * 1.0f) / (NUM_ITEMS_IN_PREVIEW - 1);
	float scale = (1 - PERSPECTIVE_SCALE_FACTOR * (1 - r));
	r = (float) Math.pow(r, 2);

	float transY = r * maxPerpectiveShift;
	float transX = (1 - scale) * baselineWidth / 2.0f;

	v = (TextView) items.get(i);
	d = v.getCompoundDrawables()[1];

	canvas.save();
	canvas.translate(transX, transY);
	canvas.scale(baselineIconScale * scale, baselineIconScale * scale);

	int overlayAlpha = (int) (80 * (1 - r));
	if (d != null) {
	d.setBounds(0, 0, d.getIntrinsicWidth(), d.getIntrinsicHeight());
	d.setColorFilter(Color.argb(overlayAlpha, 0, 0, 0), PorterDuff.Mode.SRC_ATOP);
	d.draw(canvas);
	d.clearColorFilter();
	}
	canvas.restore();
	}

	canvas.restore();
	}

	public void onAdd(ShortcutInfo item) {
	invalidate();
	requestLayout();
	}

	public void onRemove(ShortcutInfo item) {
	invalidate();
	requestLayout();
	}
	}