src/com/android/launcher2/LauncherModel.java

/*
 * 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 android.content.ComponentName;
import android.content.ContentResolver;
import android.content.ContentValues;
import android.content.Intent;
import android.content.Context;
import android.content.pm.ActivityInfo;
import android.content.pm.PackageManager;
import android.content.pm.ResolveInfo;
import android.content.res.Resources;
import android.database.Cursor;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.graphics.drawable.Drawable;
import android.net.Uri;
import static android.util.Log.*;
import android.util.Log;
import android.os.Process;
import android.os.SystemClock;

import java.lang.ref.WeakReference;
import java.net.URISyntaxException;
import java.text.Collator;
import java.util.ArrayList;
import java.util.Comparator;
import java.util.Collections;
import java.util.HashMap;
import java.util.List;

/**
 * Maintains in-memory state of the Launcher. It is expected that there should be only one
 * LauncherModel object held in a static. Also provide APIs for updating the database state
 * for the Launcher.
 */
public class LauncherModel {
    static final boolean DEBUG_LOADERS = true;
    static final String TAG = "Launcher.Model";

    private final Object mLock = new Object();
    private DeferredHandler mHandler = new DeferredHandler();
    private Loader mLoader = new Loader();

    private WeakReference<Callbacks> mCallbacks;

    private AllAppsList mAllAppsList = new AllAppsList();

    public interface Callbacks {
        public int getCurrentWorkspaceScreen();
        public void startBinding();
        public void bindItems(ArrayList<ItemInfo> shortcuts, int start, int end);
        public void finishBindingItems();
        public void bindAppWidget(LauncherAppWidgetInfo info);
        public void bindAllApplications(ArrayList<ApplicationInfo> apps);
        public void bindPackageAdded(ArrayList<ApplicationInfo> apps);
        public void bindPackageUpdated(String packageName, ArrayList<ApplicationInfo> apps);
        public void bindPackageRemoved(String packageName, ArrayList<ApplicationInfo> apps);
    }


    /**
     * Adds an item to the DB if it was not created previously, or move it to a new
     * <container, screen, cellX, cellY>
     */
    static void addOrMoveItemInDatabase(Context context, ItemInfo item, long container,
            int screen, int cellX, int cellY) {
        if (item.container == ItemInfo.NO_ID) {
            // From all apps
            addItemToDatabase(context, item, container, screen, cellX, cellY, false);
        } else {
            // From somewhere else
            moveItemInDatabase(context, item, container, screen, cellX, cellY);
        }
    }

    /**
     * Move an item in the DB to a new <container, screen, cellX, cellY>
     */
    static void moveItemInDatabase(Context context, ItemInfo item, long container, int screen,
            int cellX, int cellY) {
        item.container = container;
        item.screen = screen;
        item.cellX = cellX;
        item.cellY = cellY;

        final ContentValues values = new ContentValues();
        final ContentResolver cr = context.getContentResolver();

        values.put(LauncherSettings.Favorites.CONTAINER, item.container);
        values.put(LauncherSettings.Favorites.CELLX, item.cellX);
        values.put(LauncherSettings.Favorites.CELLY, item.cellY);
        values.put(LauncherSettings.Favorites.SCREEN, item.screen);

        cr.update(LauncherSettings.Favorites.getContentUri(item.id, false), values, null, null);
    }

    /**
     * Returns true if the shortcuts already exists in the database.
     * we identify a shortcut by its title and intent.
     */
    static boolean shortcutExists(Context context, String title, Intent intent) {
        final ContentResolver cr = context.getContentResolver();
        Cursor c = cr.query(LauncherSettings.Favorites.CONTENT_URI,
            new String[] { "title", "intent" }, "title=? and intent=?",
            new String[] { title, intent.toUri(0) }, null);
        boolean result = false;
        try {
            result = c.moveToFirst();
        } finally {
            c.close();
        }
        return result;
    }

    /**
     * Find a folder in the db, creating the FolderInfo if necessary, and adding it to folderList.
     */
    FolderInfo getFolderById(Context context, HashMap<Long,FolderInfo> folderList, long id) {
        final ContentResolver cr = context.getContentResolver();
        Cursor c = cr.query(LauncherSettings.Favorites.CONTENT_URI, null,
                "_id=? and (itemType=? or itemType=?)",
                new String[] { String.valueOf(id),
                        String.valueOf(LauncherSettings.Favorites.ITEM_TYPE_USER_FOLDER),
                        String.valueOf(LauncherSettings.Favorites.ITEM_TYPE_LIVE_FOLDER) }, null);

        try {
            if (c.moveToFirst()) {
                final int itemTypeIndex = c.getColumnIndexOrThrow(LauncherSettings.Favorites.ITEM_TYPE);
                final int titleIndex = c.getColumnIndexOrThrow(LauncherSettings.Favorites.TITLE);
                final int containerIndex = c.getColumnIndexOrThrow(LauncherSettings.Favorites.CONTAINER);
                final int screenIndex = c.getColumnIndexOrThrow(LauncherSettings.Favorites.SCREEN);
                final int cellXIndex = c.getColumnIndexOrThrow(LauncherSettings.Favorites.CELLX);
                final int cellYIndex = c.getColumnIndexOrThrow(LauncherSettings.Favorites.CELLY);

                FolderInfo folderInfo = null;
                switch (c.getInt(itemTypeIndex)) {
                    case LauncherSettings.Favorites.ITEM_TYPE_USER_FOLDER:
                        folderInfo = findOrMakeUserFolder(folderList, id);
                        break;
                    case LauncherSettings.Favorites.ITEM_TYPE_LIVE_FOLDER:
                        folderInfo = findOrMakeLiveFolder(folderList, id);
                        break;
                }

                folderInfo.title = c.getString(titleIndex);
                folderInfo.id = id;
                folderInfo.container = c.getInt(containerIndex);
                folderInfo.screen = c.getInt(screenIndex);
                folderInfo.cellX = c.getInt(cellXIndex);
                folderInfo.cellY = c.getInt(cellYIndex);

                return folderInfo;
            }
        } finally {
            c.close();
        }

        return null;
    }

    /**
     * Add an item to the database in a specified container. Sets the container, screen, cellX and
     * cellY fields of the item. Also assigns an ID to the item.
     */
    static void addItemToDatabase(Context context, ItemInfo item, long container,
            int screen, int cellX, int cellY, boolean notify) {
        item.container = container;
        item.screen = screen;
        item.cellX = cellX;
        item.cellY = cellY;

        final ContentValues values = new ContentValues();
        final ContentResolver cr = context.getContentResolver();

        item.onAddToDatabase(values);

        Uri result = cr.insert(notify ? LauncherSettings.Favorites.CONTENT_URI :
                LauncherSettings.Favorites.CONTENT_URI_NO_NOTIFICATION, values);

        if (result != null) {
            item.id = Integer.parseInt(result.getPathSegments().get(1));
        }
    }

    /**
     * Update an item to the database in a specified container.
     */
    static void updateItemInDatabase(Context context, ItemInfo item) {
        final ContentValues values = new ContentValues();
        final ContentResolver cr = context.getContentResolver();

        item.onAddToDatabase(values);

        cr.update(LauncherSettings.Favorites.getContentUri(item.id, false), values, null, null);
    }

    /**
     * Removes the specified item from the database
     * @param context
     * @param item
     */
    static void deleteItemFromDatabase(Context context, ItemInfo item) {
        final ContentResolver cr = context.getContentResolver();

        cr.delete(LauncherSettings.Favorites.getContentUri(item.id, false), null, null);
    }

    /**
     * Remove the contents of the specified folder from the database
     */
    static void deleteUserFolderContentsFromDatabase(Context context, UserFolderInfo info) {
        final ContentResolver cr = context.getContentResolver();

        cr.delete(LauncherSettings.Favorites.getContentUri(info.id, false), null, null);
        cr.delete(LauncherSettings.Favorites.CONTENT_URI,
                LauncherSettings.Favorites.CONTAINER + "=" + info.id, null);
    }

    /**
     * Set this as the current Launcher activity object for the loader.
     */
    public void initialize(Callbacks callbacks) {
        synchronized (mLock) {
            mCallbacks = new WeakReference<Callbacks>(callbacks);
        }
    }

    public void startLoader(Context context, boolean isLaunching) {
        mLoader.startLoader(context, isLaunching);
    }

    public void stopLoader() {
        mLoader.stopLoader();
    }

    public void setWorkspaceDirty() {
        mLoader.setWorkspaceDirty();
    }

    /**
     * Call from the handler for ACTION_PACKAGE_ADDED, ACTION_PACKAGE_REMOVED and
     * ACTION_PACKAGE_CHANGED.
     */
    public void onReceiveIntent(Context context, Intent intent) {
        final String packageName = intent.getData().getSchemeSpecificPart();

        ArrayList<ApplicationInfo> added = null;
        ArrayList<ApplicationInfo> removed = null;
        ArrayList<ApplicationInfo> modified = null;
        boolean update = false;
        boolean remove = false;

        synchronized (mLock) {
            final String action = intent.getAction();
            final boolean replacing = intent.getBooleanExtra(Intent.EXTRA_REPLACING, false);

            if (packageName == null || packageName.length() == 0) {
                // they sent us a bad intent
                return;
            }

            if (Intent.ACTION_PACKAGE_CHANGED.equals(action)) {
                mAllAppsList.updatePackage(context, packageName);
                update = true;
            } else if (Intent.ACTION_PACKAGE_REMOVED.equals(action)) {
                if (!replacing) {
                    mAllAppsList.removePackage(packageName);
                    remove = true;
                }
                // else, we are replacing the package, so a PACKAGE_ADDED will be sent
                // later, we will update the package at this time
            } else {
                if (!replacing) {
                    mAllAppsList.addPackage(context, packageName);
                } else {
                    mAllAppsList.updatePackage(context, packageName);
                    update = true;
                }
            }

            if (mAllAppsList.added.size() > 0) {
                added = mAllAppsList.added;
                added = new ArrayList();
            }
            if (mAllAppsList.removed.size() > 0) {
                removed = mAllAppsList.removed;
                removed = new ArrayList();
                for (ApplicationInfo info: removed) {
                    AppInfoCache.remove(info.intent.getComponent());
                }
            }
            if (mAllAppsList.modified.size() > 0) {
                modified = mAllAppsList.modified;
                modified = new ArrayList();
            }

            final Callbacks callbacks = mCallbacks.get();
            if (callbacks == null) {
                return;
            }

            if (added != null) {
                final ArrayList<ApplicationInfo> addedFinal = added;
                mHandler.post(new Runnable() {
                    public void run() {
                        callbacks.bindPackageAdded(addedFinal);
                    }
                });
            }
            if (update || modified != null) {
                final ArrayList<ApplicationInfo> modifiedFinal = modified;
                mHandler.post(new Runnable() {
                    public void run() {
                        callbacks.bindPackageUpdated(packageName, modifiedFinal);
                    }
                });
            }
            if (remove || removed != null) {
                final ArrayList<ApplicationInfo> removedFinal = removed;
                mHandler.post(new Runnable() {
                    public void run() {
                        callbacks.bindPackageRemoved(packageName, removedFinal);
                    }
                });
            }
        }
    }

    public class Loader {
        private static final int ITEMS_CHUNK = 6;

        private LoaderThread mLoaderThread;

        private int mLastWorkspaceSeq = 0;
        private int mWorkspaceSeq = 1;

        private int mLastAllAppsSeq = 0;
        private int mAllAppsSeq = 1;

        final ArrayList<ItemInfo> mItems = new ArrayList();
        final ArrayList<LauncherAppWidgetInfo> mAppWidgets = new ArrayList();
        final HashMap<Long, FolderInfo> folders = new HashMap();
                
        /**
         * Call this from the ui thread so the handler is initialized on the correct thread.
         */
        public Loader() {
        }

        public void startLoader(Context context, boolean isLaunching) {
            synchronized (mLock) {
                Log.d(TAG, "startLoader isLaunching=" + isLaunching);
                // Don't bother to start the thread if we know it's not going to do anything
                if (mCallbacks.get() != null) {
                    LoaderThread oldThread = mLoaderThread;
                    if (oldThread != null) {
                        if (oldThread.isLaunching()) {
                            // don't downgrade isLaunching if we're already running
                            isLaunching = true;
                        }
                        oldThread.stopLocked();
                    }
                    mLoaderThread = new LoaderThread(context, oldThread, isLaunching);
                    mLoaderThread.start();
                }
            }
        }

        public void stopLoader() {
            synchronized (mLock) {
                if (mLoaderThread != null) {
                    mLoaderThread.stopLocked();
                }
            }
        }

        public void setWorkspaceDirty() {
            synchronized (mLock) {
                mWorkspaceSeq++;
            }
        }

        public void setAllAppsDirty() {
            synchronized (mLock) {
                mAllAppsSeq++;
            }
        }

        /**
         * Runnable for the thread that loads the contents of the launcher:
         *   - workspace icons
         *   - widgets
         *   - all apps icons
         */
        private class LoaderThread extends Thread {
            private Context mContext;
            private Thread mWaitThread;
            private boolean mIsLaunching;
            private boolean mStopped;
            private boolean mWorkspaceDoneBinding;

            LoaderThread(Context context, Thread waitThread, boolean isLaunching) {
                mContext = context;
                mWaitThread = waitThread;
                mIsLaunching = isLaunching;
            }

            boolean isLaunching() {
                return mIsLaunching;
            }

            /**
             * If another LoaderThread was supplied, we need to wait for that to finish before
             * we start our processing.  This keeps the ordering of the setting and clearing
             * of the dirty flags correct by making sure we don't start processing stuff until
             * they've had a chance to re-set them.  We do this waiting the worker thread, not
             * the ui thread to avoid ANRs.
             */
            private void waitForOtherThread() {
                if (mWaitThread != null) {
                    boolean done = false;
                    while (!done) {
                        try {
                            mWaitThread.join();
                        } catch (InterruptedException ex) {
                        }
                    }
                    mWaitThread = null;
                }
            }

            public void run() {
                waitForOtherThread();

                // Elevate priority when Home launches for the first time to avoid
                // starving at boot time. Staring at a blank home is not cool.
                synchronized (mLock) {
                    android.os.Process.setThreadPriority(mIsLaunching
                            ? Process.THREAD_PRIORITY_DEFAULT : Process.THREAD_PRIORITY_BACKGROUND);
                }

                // Load the workspace only if it's dirty.
                int workspaceSeq;
                boolean workspaceDirty;
                synchronized (mLock) {
                    workspaceSeq = mWorkspaceSeq;
                    workspaceDirty = mWorkspaceSeq != mLastWorkspaceSeq;
                }
                if (workspaceDirty) {
                    loadWorkspace();
                }
                synchronized (mLock) {
                    // If we're not stopped, and nobody has incremented mWorkspaceSeq.
                    if (mStopped) {
                        return;
                    }
                    if (workspaceSeq == mWorkspaceSeq) {
                        mLastWorkspaceSeq = mWorkspaceSeq;
                    }
                }

                // Bind the workspace
                bindWorkspace();
                
                // Wait until the either we're stopped or the other threads are done.
                // This way we don't start loading all apps until the workspace has settled
                // down.
                synchronized (LoaderThread.this) {
                    mHandler.post(new Runnable() {
                            public void run() {
                                synchronized (LoaderThread.this) {
                                    mWorkspaceDoneBinding = true;
                                    Log.d(TAG, "done with workspace");
                                    LoaderThread.this.notify();
                                }
                            }
                        });
                    Log.d(TAG, "waiting to be done with workspace");
                    while (!mStopped && !mWorkspaceDoneBinding) {
                        try {
                            this.wait();
                        } catch (InterruptedException ex) {
                        }
                    }
                    Log.d(TAG, "done waiting to be done with workspace");
                }

                // Load all apps if they're dirty
                int allAppsSeq;
                boolean allAppsDirty;
                synchronized (mLock) {
                    allAppsSeq = mAllAppsSeq;
                    allAppsDirty = mAllAppsSeq != mLastAllAppsSeq;
                }
                if (allAppsDirty) {
                    loadAllApps();
                }
                synchronized (mLock) {
                    // If we're not stopped, and nobody has incremented mAllAppsSeq.
                    if (mStopped) {
                        return;
                    }
                    if (allAppsSeq == mAllAppsSeq) {
                        mLastAllAppsSeq = mAllAppsSeq;
                    }
                }

                // Bind all apps
                bindAllApps();

                // Clear out this reference, otherwise we end up holding it until all of the
                // callback runnables are done.
                mContext = null;

                synchronized (mLock) {
                    // Setting the reference is atomic, but we can't do it inside the other critical
                    // sections.
                    mLoaderThread = null;
                    return;
                }
            }

            public void stopLocked() {
                synchronized (LoaderThread.this) {
                    mStopped = true;
                    this.notify();
                }
            }

            /**
             * Gets the callbacks object.  If we've been stopped, or if the launcher object
             * has somehow been garbage collected, return null instead.
             */
            Callbacks tryGetCallbacks() {
                synchronized (mLock) {
                    if (mStopped) {
                        return null;
                    }

                    final Callbacks callbacks = mCallbacks.get();
                    if (callbacks == null) {
                        Log.w(TAG, "no mCallbacks");
                        return null;
                    }

                    return callbacks;
                }
            }

            private void loadWorkspace() {
                long t = SystemClock.uptimeMillis();

                final Context context = mContext;
                final ContentResolver contentResolver = context.getContentResolver();
                final PackageManager manager = context.getPackageManager();

                /* TODO
                if (mLocaleChanged) {
                    updateShortcutLabels(contentResolver, manager);
                }
                */

                final Cursor c = contentResolver.query(
                        LauncherSettings.Favorites.CONTENT_URI, null, null, null, null);

                try {
                    final int idIndex = c.getColumnIndexOrThrow(LauncherSettings.Favorites._ID);
                    final int intentIndex = c.getColumnIndexOrThrow
                            (LauncherSettings.Favorites.INTENT);
                    final int titleIndex = c.getColumnIndexOrThrow
                            (LauncherSettings.Favorites.TITLE);
                    final int iconTypeIndex = c.getColumnIndexOrThrow(
                            LauncherSettings.Favorites.ICON_TYPE);
                    final int iconIndex = c.getColumnIndexOrThrow(LauncherSettings.Favorites.ICON);
                    final int iconPackageIndex = c.getColumnIndexOrThrow(
                            LauncherSettings.Favorites.ICON_PACKAGE);
                    final int iconResourceIndex = c.getColumnIndexOrThrow(
                            LauncherSettings.Favorites.ICON_RESOURCE);
                    final int containerIndex = c.getColumnIndexOrThrow(
                            LauncherSettings.Favorites.CONTAINER);
                    final int itemTypeIndex = c.getColumnIndexOrThrow(
                            LauncherSettings.Favorites.ITEM_TYPE);
                    final int appWidgetIdIndex = c.getColumnIndexOrThrow(
                            LauncherSettings.Favorites.APPWIDGET_ID);
                    final int screenIndex = c.getColumnIndexOrThrow(
                            LauncherSettings.Favorites.SCREEN);
                    final int cellXIndex = c.getColumnIndexOrThrow
                            (LauncherSettings.Favorites.CELLX);
                    final int cellYIndex = c.getColumnIndexOrThrow
                            (LauncherSettings.Favorites.CELLY);
                    final int spanXIndex = c.getColumnIndexOrThrow
                            (LauncherSettings.Favorites.SPANX);
                    final int spanYIndex = c.getColumnIndexOrThrow(
                            LauncherSettings.Favorites.SPANY);
                    final int uriIndex = c.getColumnIndexOrThrow(LauncherSettings.Favorites.URI);
                    final int displayModeIndex = c.getColumnIndexOrThrow(
                            LauncherSettings.Favorites.DISPLAY_MODE);

                    ApplicationInfo info;
                    String intentDescription;
                    Widget widgetInfo;
                    LauncherAppWidgetInfo appWidgetInfo;
                    int container;
                    long id;
                    Intent intent;

                    while (!mStopped && c.moveToNext()) {
                        try {
                            int itemType = c.getInt(itemTypeIndex);

                            switch (itemType) {
                            case LauncherSettings.Favorites.ITEM_TYPE_APPLICATION:
                            case LauncherSettings.Favorites.ITEM_TYPE_SHORTCUT:
                                intentDescription = c.getString(intentIndex);
                                try {
                                    intent = Intent.parseUri(intentDescription, 0);
                                } catch (URISyntaxException e) {
                                    continue;
                                }

                                if (itemType == LauncherSettings.Favorites.ITEM_TYPE_APPLICATION) {
                                    info = getApplicationInfo(manager, intent, context);
                                } else {
                                    info = getApplicationInfoShortcut(c, context, iconTypeIndex,
                                            iconPackageIndex, iconResourceIndex, iconIndex);
                                }

                                if (info == null) {
                                    info = new ApplicationInfo();
                                    info.icon = manager.getDefaultActivityIcon();
                                }

                                if (info != null) {
                                    info.title = c.getString(titleIndex);
                                    info.intent = intent;

                                    info.id = c.getLong(idIndex);
                                    container = c.getInt(containerIndex);
                                    info.container = container;
                                    info.screen = c.getInt(screenIndex);
                                    info.cellX = c.getInt(cellXIndex);
                                    info.cellY = c.getInt(cellYIndex);

                                    switch (container) {
                                    case LauncherSettings.Favorites.CONTAINER_DESKTOP:
                                        mItems.add(info);
                                        break;
                                    default:
                                        // Item is in a user folder
                                        UserFolderInfo folderInfo =
                                                findOrMakeUserFolder(folders, container);
                                        folderInfo.add(info);
                                        break;
                                    }
                                }
                                break;
                            case LauncherSettings.Favorites.ITEM_TYPE_USER_FOLDER:

                                id = c.getLong(idIndex);
                                UserFolderInfo folderInfo = findOrMakeUserFolder(folders, id);

                                folderInfo.title = c.getString(titleIndex);

                                folderInfo.id = id;
                                container = c.getInt(containerIndex);
                                folderInfo.container = container;
                                folderInfo.screen = c.getInt(screenIndex);
                                folderInfo.cellX = c.getInt(cellXIndex);
                                folderInfo.cellY = c.getInt(cellYIndex);

                                switch (container) {
                                    case LauncherSettings.Favorites.CONTAINER_DESKTOP:
                                        mItems.add(folderInfo);
                                        break;
                                }
                                break;
                            case LauncherSettings.Favorites.ITEM_TYPE_LIVE_FOLDER:

                                id = c.getLong(idIndex);
                                LiveFolderInfo liveFolderInfo = findOrMakeLiveFolder(folders, id);

                                intentDescription = c.getString(intentIndex);
                                intent = null;
                                if (intentDescription != null) {
                                    try {
                                        intent = Intent.parseUri(intentDescription, 0);
                                    } catch (URISyntaxException e) {
                                        // Ignore, a live folder might not have a base intent
                                    }
                                }

                                liveFolderInfo.title = c.getString(titleIndex);
                                liveFolderInfo.id = id;
                                container = c.getInt(containerIndex);
                                liveFolderInfo.container = container;
                                liveFolderInfo.screen = c.getInt(screenIndex);
                                liveFolderInfo.cellX = c.getInt(cellXIndex);
                                liveFolderInfo.cellY = c.getInt(cellYIndex);
                                liveFolderInfo.uri = Uri.parse(c.getString(uriIndex));
                                liveFolderInfo.baseIntent = intent;
                                liveFolderInfo.displayMode = c.getInt(displayModeIndex);

                                loadLiveFolderIcon(context, c, iconTypeIndex, iconPackageIndex,
                                        iconResourceIndex, liveFolderInfo);

                                switch (container) {
                                    case LauncherSettings.Favorites.CONTAINER_DESKTOP:
                                        mItems.add(liveFolderInfo);
                                        break;
                                }
                                break;
                            case LauncherSettings.Favorites.ITEM_TYPE_WIDGET_SEARCH:
                                widgetInfo = Widget.makeSearch();

                                container = c.getInt(containerIndex);
                                if (container != LauncherSettings.Favorites.CONTAINER_DESKTOP) {
                                    Log.e(TAG, "Widget found where container "
                                            + "!= CONTAINER_DESKTOP  ignoring!");
                                    continue;
                                }

                                widgetInfo.id = c.getLong(idIndex);
                                widgetInfo.screen = c.getInt(screenIndex);
                                widgetInfo.container = container;
                                widgetInfo.cellX = c.getInt(cellXIndex);
                                widgetInfo.cellY = c.getInt(cellYIndex);

                                mItems.add(widgetInfo);
                                break;
                            case LauncherSettings.Favorites.ITEM_TYPE_APPWIDGET:
                                // Read all Launcher-specific widget details
                                int appWidgetId = c.getInt(appWidgetIdIndex);
                                appWidgetInfo = new LauncherAppWidgetInfo(appWidgetId);
                                appWidgetInfo.id = c.getLong(idIndex);
                                appWidgetInfo.screen = c.getInt(screenIndex);
                                appWidgetInfo.cellX = c.getInt(cellXIndex);
                                appWidgetInfo.cellY = c.getInt(cellYIndex);
                                appWidgetInfo.spanX = c.getInt(spanXIndex);
                                appWidgetInfo.spanY = c.getInt(spanYIndex);

                                container = c.getInt(containerIndex);
                                if (container != LauncherSettings.Favorites.CONTAINER_DESKTOP) {
                                    Log.e(TAG, "Widget found where container "
                                            + "!= CONTAINER_DESKTOP -- ignoring!");
                                    continue;
                                }
                                appWidgetInfo.container = c.getInt(containerIndex);

                                mAppWidgets.add(appWidgetInfo);
                                break;
                            }
                        } catch (Exception e) {
                            Log.w(TAG, "Desktop items loading interrupted:", e);
                        }
                    }
                } finally {
                    c.close();
                }
                Log.d(TAG, "loaded workspace in " + (SystemClock.uptimeMillis()-t) + "ms");
            }

            /**
             * Read everything out of our database.
             */
            private void bindWorkspace() {
                final long t = SystemClock.uptimeMillis();

                // Don't use these two variables in any of the callback runnables.
                // Otherwise we hold a reference to them.
                Callbacks callbacks = mCallbacks.get();
                if (callbacks == null) {
                    // This launcher has exited and nobody bothered to tell us.  Just bail.
                    Log.w(TAG, "LoaderThread running with no launcher");
                    return;
                }

                int N;
                // Tell the workspace that we're about to start firing items at it
                mHandler.post(new Runnable() {
                    public void run() {
                        Callbacks callbacks = tryGetCallbacks();
                        if (callbacks != null) {
                            callbacks.startBinding();
                        }
                    }
                });
                // Add the items to the workspace.
                N = mItems.size();
                for (int i=0; i<N; i+=ITEMS_CHUNK) {
                    final int start = i;
                    final int chunkSize = (i+ITEMS_CHUNK <= N) ? ITEMS_CHUNK : (N-i);
                    mHandler.post(new Runnable() {
                        public void run() {
                            Callbacks callbacks = tryGetCallbacks();
                            if (callbacks != null) {
                                callbacks.bindItems(mItems, start, start+chunkSize);
                            }
                        }
                    });
                }
                // Wait until the queue goes empty.
                mHandler.postIdle(new Runnable() {
                    public void run() {
                        Log.d(TAG, "Going to start binding widgets soon.");
                    }
                });
                // Bind the widgets, one at a time.
                // WARNING: this is calling into the workspace from the background thread,
                // but since getCurrentScreen() just returns the int, we should be okay.  This
                // is just a hint for the order, and if it's wrong, we'll be okay.
                // TODO: instead, we should have that push the current screen into here.
                final int currentScreen = callbacks.getCurrentWorkspaceScreen();
                N = mAppWidgets.size();
                // once for the current screen
                for (int i=0; i<N; i++) {
                    final LauncherAppWidgetInfo widget = mAppWidgets.get(i);
                    if (widget.screen == currentScreen) {
                        mHandler.post(new Runnable() {
                            public void run() {
                                Callbacks callbacks = tryGetCallbacks();
                                if (callbacks != null) {
                                    callbacks.bindAppWidget(widget);
                                }
                            }
                        });
                    }
                }
                // once for the other screens
                for (int i=0; i<N; i++) {
                    final LauncherAppWidgetInfo widget = mAppWidgets.get(i);
                    if (widget.screen != currentScreen) {
                        mHandler.post(new Runnable() {
                            public void run() {
                                Callbacks callbacks = tryGetCallbacks();
                                if (callbacks != null) {
                                    callbacks.bindAppWidget(widget);
                                }
                            }
                        });
                    }
                }
                // TODO: Bind the folders
                // Tell the workspace that we're done.
                mHandler.post(new Runnable() {
                    public void run() {
                        Callbacks callbacks = tryGetCallbacks();
                        if (callbacks != null) {
                            callbacks.finishBindingItems();
                        }
                    }
                });
                // If we're profiling, this is the last thing in the queue.
                mHandler.post(new Runnable() {
                    public void run() {
                        Log.d(TAG, "bound workspace in " + (SystemClock.uptimeMillis()-t) + "ms");
                        if (Launcher.PROFILE_ROTATE) {
                            android.os.Debug.stopMethodTracing();
                        }
                    }
                });
            }

            private void loadAllApps() {
                final Intent mainIntent = new Intent(Intent.ACTION_MAIN, null);
                mainIntent.addCategory(Intent.CATEGORY_LAUNCHER);

                final Callbacks callbacks = tryGetCallbacks();
                if (callbacks == null) {
                    return;
                }

                final Context context = mContext;
                final PackageManager packageManager = context.getPackageManager();

                final List<ResolveInfo> apps = packageManager.queryIntentActivities(mainIntent, 0);

                synchronized (mLock) {
                    mAllAppsList.clear();
                    if (apps != null) {
                        long t = SystemClock.uptimeMillis();

                        int N = apps.size();
                        Utilities.BubbleText bubble = new Utilities.BubbleText(context);
                        for (int i=0; i<N && !mStopped; i++) {
                            // This builds the icon bitmaps.
                            mAllAppsList.add(AppInfoCache.cache(apps.get(i), context, bubble));
                        }
                        Collections.sort(mAllAppsList.data, sComparator);
                        Collections.sort(mAllAppsList.added, sComparator);
                        Log.d(TAG, "cached app icons in " + (SystemClock.uptimeMillis()-t) + "ms");
                    }
                }
            }

            private void bindAllApps() {
                synchronized (mLock) {
                    final ArrayList<ApplicationInfo> results = mAllAppsList.added;
                    mAllAppsList.added = new ArrayList();
                    mHandler.post(new Runnable() {
                        public void run() {
                            long t = SystemClock.uptimeMillis();

                            Callbacks callbacks = tryGetCallbacks();
                            if (callbacks != null) {
                                callbacks.bindAllApplications(results);
                            }

                            Log.d(TAG, "bound app icons in "
                                + (SystemClock.uptimeMillis()-t) + "ms");
                        }
                    });
                }
            }
        }
    }

    /**
     * Make an ApplicationInfo object for an application.
     */
    private static ApplicationInfo getApplicationInfo(PackageManager manager, Intent intent,
                                                      Context context) {
        final ResolveInfo resolveInfo = manager.resolveActivity(intent, 0);

        if (resolveInfo == null) {
            return null;
        }

        final ApplicationInfo info = new ApplicationInfo();
        final ActivityInfo activityInfo = resolveInfo.activityInfo;
        info.icon = Utilities.createIconThumbnail(activityInfo.loadIcon(manager), context, false);
        if (info.title == null || info.title.length() == 0) {
            info.title = activityInfo.loadLabel(manager);
        }
        if (info.title == null) {
            info.title = "";
        }
        info.itemType = LauncherSettings.Favorites.ITEM_TYPE_APPLICATION;
        return info;
    }

    /**
     * Make an ApplicationInfo object for a sortcut
     */
    private static ApplicationInfo getApplicationInfoShortcut(Cursor c, Context context,
            int iconTypeIndex, int iconPackageIndex, int iconResourceIndex, int iconIndex) {

        final ApplicationInfo info = new ApplicationInfo();
        info.itemType = LauncherSettings.Favorites.ITEM_TYPE_SHORTCUT;

        int iconType = c.getInt(iconTypeIndex);
        switch (iconType) {
        case LauncherSettings.Favorites.ICON_TYPE_RESOURCE:
            String packageName = c.getString(iconPackageIndex);
            String resourceName = c.getString(iconResourceIndex);
            PackageManager packageManager = context.getPackageManager();
            try {
                Resources resources = packageManager.getResourcesForApplication(packageName);
                final int id = resources.getIdentifier(resourceName, null, null);
                info.icon = Utilities.createIconThumbnail(resources.getDrawable(id), context,
                        false);
            } catch (Exception e) {
                info.icon = packageManager.getDefaultActivityIcon();
            }
            info.iconResource = new Intent.ShortcutIconResource();
            info.iconResource.packageName = packageName;
            info.iconResource.resourceName = resourceName;
            info.customIcon = false;
            break;
        case LauncherSettings.Favorites.ICON_TYPE_BITMAP:
            byte[] data = c.getBlob(iconIndex);
            try {
                Bitmap bitmap = BitmapFactory.decodeByteArray(data, 0, data.length);
                info.icon = new FastBitmapDrawable(
                        Utilities.createBitmapThumbnail(bitmap, context));
            } catch (Exception e) {
                packageManager = context.getPackageManager();
                info.icon = packageManager.getDefaultActivityIcon();
            }
            info.filtered = true;
            info.customIcon = true;
            break;
        default:
            info.icon = context.getPackageManager().getDefaultActivityIcon();
            info.customIcon = false;
            break;
        }
        return info;
    }

    private static void loadLiveFolderIcon(Context context, Cursor c, int iconTypeIndex,
            int iconPackageIndex, int iconResourceIndex, LiveFolderInfo liveFolderInfo) {

        int iconType = c.getInt(iconTypeIndex);
        switch (iconType) {
        case LauncherSettings.Favorites.ICON_TYPE_RESOURCE:
            String packageName = c.getString(iconPackageIndex);
            String resourceName = c.getString(iconResourceIndex);
            PackageManager packageManager = context.getPackageManager();
            try {
                Resources resources = packageManager.getResourcesForApplication(packageName);
                final int id = resources.getIdentifier(resourceName, null, null);
                liveFolderInfo.icon = resources.getDrawable(id);
            } catch (Exception e) {
                liveFolderInfo.icon =
                        context.getResources().getDrawable(R.drawable.ic_launcher_folder);
            }
            liveFolderInfo.iconResource = new Intent.ShortcutIconResource();
            liveFolderInfo.iconResource.packageName = packageName;
            liveFolderInfo.iconResource.resourceName = resourceName;
            break;
        default:
            liveFolderInfo.icon =
                    context.getResources().getDrawable(R.drawable.ic_launcher_folder);
        }
    }

    /**
     * Return an existing UserFolderInfo object if we have encountered this ID previously,
     * or make a new one.
     */
    private static UserFolderInfo findOrMakeUserFolder(HashMap<Long, FolderInfo> folders, long id) {
        // See if a placeholder was created for us already
        FolderInfo folderInfo = folders.get(id);
        if (folderInfo == null || !(folderInfo instanceof UserFolderInfo)) {
            // No placeholder -- create a new instance
            folderInfo = new UserFolderInfo();
            folders.put(id, folderInfo);
        }
        return (UserFolderInfo) folderInfo;
    }

    /**
     * Return an existing UserFolderInfo object if we have encountered this ID previously, or make a
     * new one.
     */
    private static LiveFolderInfo findOrMakeLiveFolder(HashMap<Long, FolderInfo> folders, long id) {
        // See if a placeholder was created for us already
        FolderInfo folderInfo = folders.get(id);
        if (folderInfo == null || !(folderInfo instanceof LiveFolderInfo)) {
            // No placeholder -- create a new instance
            folderInfo = new LiveFolderInfo();
            folders.put(id, folderInfo);
        }
        return (LiveFolderInfo) folderInfo;
    }

    private static void updateShortcutLabels(ContentResolver resolver, PackageManager manager) {
        final Cursor c = resolver.query(LauncherSettings.Favorites.CONTENT_URI,
                new String[] { LauncherSettings.Favorites._ID, LauncherSettings.Favorites.TITLE,
                        LauncherSettings.Favorites.INTENT, LauncherSettings.Favorites.ITEM_TYPE },
                null, null, null);

        final int idIndex = c.getColumnIndexOrThrow(LauncherSettings.Favorites._ID);
        final int intentIndex = c.getColumnIndexOrThrow(LauncherSettings.Favorites.INTENT);
        final int itemTypeIndex = c.getColumnIndexOrThrow(LauncherSettings.Favorites.ITEM_TYPE);
        final int titleIndex = c.getColumnIndexOrThrow(LauncherSettings.Favorites.TITLE);

        // boolean changed = false;

        try {
            while (c.moveToNext()) {
                try {
                    if (c.getInt(itemTypeIndex) !=
                            LauncherSettings.Favorites.ITEM_TYPE_APPLICATION) {
                        continue;
                    }

                    final String intentUri = c.getString(intentIndex);
                    if (intentUri != null) {
                        final Intent shortcut = Intent.parseUri(intentUri, 0);
                        if (Intent.ACTION_MAIN.equals(shortcut.getAction())) {
                            final ComponentName name = shortcut.getComponent();
                            if (name != null) {
                                final ActivityInfo activityInfo = manager.getActivityInfo(name, 0);
                                final String title = c.getString(titleIndex);
                                String label = getLabel(manager, activityInfo);

                                if (title == null || !title.equals(label)) {
                                    final ContentValues values = new ContentValues();
                                    values.put(LauncherSettings.Favorites.TITLE, label);

                                    resolver.update(
                                            LauncherSettings.Favorites.CONTENT_URI_NO_NOTIFICATION,
                                            values, "_id=?",
                                            new String[] { String.valueOf(c.getLong(idIndex)) });

                                    // changed = true;
                                }
                            }
                        }
                    }
                } catch (URISyntaxException e) {
                    // Ignore
                } catch (PackageManager.NameNotFoundException e) {
                    // Ignore
                }
            }
        } finally {
            c.close();
        }

        // if (changed) resolver.notifyChange(Settings.Favorites.CONTENT_URI, null);
    }

    private static String getLabel(PackageManager manager, ActivityInfo activityInfo) {
        String label = activityInfo.loadLabel(manager).toString();
        if (label == null) {
            label = manager.getApplicationLabel(activityInfo.applicationInfo).toString();
            if (label == null) {
                label = activityInfo.name;
            }
        }
        return label;
    }

    private static final Collator sCollator = Collator.getInstance();
    private static final Comparator<ApplicationInfo> sComparator
            = new Comparator<ApplicationInfo>() {
        public final int compare(ApplicationInfo a, ApplicationInfo b) {
            return sCollator.compare(a.title.toString(), b.title.toString());
        }
    };
}