launcher5.0-资源加载

桌面启动

执行LauncherApplication.java ----onCreate()方法

@Override
    public void onCreate() {
        super.onCreate();

        // set sIsScreenXLarge and sScreenDensity *before* creating icon cache
        sIsScreenLarge = getResources().getBoolean(R.bool.is_large_screen);
        sScreenDensity = getResources().getDisplayMetrics().density;

        recreateWidgetPreviewDb();
        mIconCache = new IconCache(this);
        mModel = new LauncherModel(this, mIconCache);
        LauncherApps launcherApps = (LauncherApps)
                getSystemService(Context.LAUNCHER_APPS_SERVICE);
        launcherApps.registerCallback(mModel.getLauncherAppsCallback());

        // Register intent receivers
        IntentFilter filter = new IntentFilter();
        filter.addAction(Intent.ACTION_LOCALE_CHANGED);
        filter.addAction(Intent.ACTION_CONFIGURATION_CHANGED);
        registerReceiver(mModel, filter);
        filter = new IntentFilter();
        filter.addAction(SearchManager.INTENT_GLOBAL_SEARCH_ACTIVITY_CHANGED);
        registerReceiver(mModel, filter);
        filter = new IntentFilter();
        filter.addAction(SearchManager.INTENT_ACTION_SEARCHABLES_CHANGED);
        registerReceiver(mModel, filter);

        // Register for changes to the favorites
        ContentResolver resolver = getContentResolver();
        resolver.registerContentObserver(LauncherSettings.Favorites.CONTENT_URI, true,
                mFavoritesObserver);
    }

注册 favorites observer

    /**
     * Receives notifications whenever the user favorites have changed.
     */
    private final ContentObserver mFavoritesObserver = new ContentObserver(new Handler()) {
        @Override
        public void onChange(boolean selfChange) {
            // If the database has ever changed, then we really need to force a reload of the
            // workspace on the next load
            mModel.resetLoadedState(false, true);
            mModel.startLoaderFromBackground();
        }
    };

执行 mModel.startLoaderFromBackground();

    /**
     * When the launcher is in the background, it's possible for it to miss paired
     * configuration changes.  So whenever we trigger the loader from the background
     * tell the launcher that it needs to re-run the loader when it comes back instead
     * of doing it now.
     */
    public void startLoaderFromBackground() {
        boolean runLoader = false;
        if (mCallbacks != null) {
            Callbacks callbacks = mCallbacks.get();
            if (callbacks != null) {
                // Only actually run the loader if they're not paused.
                if (!callbacks.setLoadOnResume()) {
                    runLoader = true;
                }
            }
        }
        if (runLoader) {
            startLoader(false, -1);
        }
    }

执行 startLoader(false, -1);

public void startLoader(boolean isLaunching, int synchronousBindPage) {
        synchronized (mLock) {
            if (DEBUG_LOADERS) {
                Log.d(TAG, "startLoader isLaunching=" + isLaunching);
            }

            // Clear any deferred bind-runnables from the synchronized load process
            // We must do this before any loading/binding is scheduled below.
            mDeferredBindRunnables.clear();

            // Don't bother to start the thread if we know it's not going to do anything
            if (mCallbacks != null && mCallbacks.get() != null) {
                // If there is already one running, tell it to stop.
                // also, don't downgrade isLaunching if we're already running
                isLaunching = isLaunching || stopLoaderLocked();
                mLoaderTask = new LoaderTask(mApp, isLaunching);
                if (synchronousBindPage > -1 && mAllAppsLoaded && mWorkspaceLoaded) {
                    mLoaderTask.runBindSynchronousPage(synchronousBindPage);
                } else {
                    sWorkerThread.setPriority(Thread.NORM_PRIORITY);
                    sWorker.post(mLoaderTask);
                }
            }
        }
    }

如上加载资源执行mLoaderTask ,mLoaderTask implements Runnable 方法 看下mLoaderTask run

   public void run() {
            synchronized (mLock) {
                mIsLoaderTaskRunning = true;
            }

            keep_running: {
                // 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) {
                    if (DEBUG_LOADERS) Log.d(TAG, "Setting thread priority to " +
                            (mIsLaunching ? "DEFAULT" : "BACKGROUND"));
                    Process.setThreadPriority(mIsLaunching
                            ? Process.THREAD_PRIORITY_DEFAULT : Process.THREAD_PRIORITY_BACKGROUND);
                }

                // First step. Load workspace first, this is necessary since adding of apps from
                // managed profile in all apps is deferred until onResume. See http://b/17336902.
                if (DEBUG_LOADERS) Log.d(TAG, "step 1: loading workspace");
                loadAndBindWorkspace();

                if (mStopped) {
                    break keep_running;
                }

                // Whew! Hard work done.  Slow us down, and wait until the UI thread has
                // settled down.
                synchronized (mLock) {
                    if (mIsLaunching) {
                        if (DEBUG_LOADERS) Log.d(TAG, "Setting thread priority to BACKGROUND");
                        Process.setThreadPriority(Process.THREAD_PRIORITY_BACKGROUND);
                    }
                }
                waitForIdle();

                // Second step. Load all apps.
                if (DEBUG_LOADERS) Log.d(TAG, "step 2: loading all apps");
                loadAndBindAllApps();

                // Restore the default thread priority after we are done loading items
                synchronized (mLock) {
                    Process.setThreadPriority(Process.THREAD_PRIORITY_DEFAULT);
                }
            }


            // Update the saved icons if necessary
            if (DEBUG_LOADERS) Log.d(TAG, "Comparing loaded icons to database icons");
            synchronized (sBgLock) {
                for (Object key : sBgDbIconCache.keySet()) {
                    updateSavedIcon(mContext, (ShortcutInfo) key, sBgDbIconCache.get(key));
                }
                sBgDbIconCache.clear();
            }

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

            synchronized (mLock) {
                // If we are still the last one to be scheduled, remove ourselves.
                if (mLoaderTask == this) {
                    mLoaderTask = null;
                }
                mIsLoaderTaskRunning = false;
            }
        }

    loadAndBindWorkspace()方法是加载和绑定桌面资源 (从资源文件和旧偏好)

　 loadAndBindAllApps（）桌面绑定app信息

 private void loadAndBindWorkspace() {
            mIsLoadingAndBindingWorkspace = true;

            // Load the workspace
            if (DEBUG_LOADERS) {
                Log.d(TAG, "loadAndBindWorkspace mWorkspaceLoaded=" + mWorkspaceLoaded);
            }

            if (!mWorkspaceLoaded) {
                loadWorkspace();
                synchronized (LoaderTask.this) {
                    if (mStopped) {
                        return;
                    }
                    mWorkspaceLoaded = true;
                }
            }

            // Bind the workspace
            bindWorkspace(-1);
        }

　　

loadWorkspace()加载桌面资源

bindWorkspace()绑定资源到桌面

  private void loadWorkspace() {
            final long t = DEBUG_LOADERS ? SystemClock.uptimeMillis() : 0;

            final Context context = mContext;
            final ContentResolver contentResolver = context.getContentResolver();
            final PackageManager manager = context.getPackageManager();
            final AppWidgetManager widgets = AppWidgetManager.getInstance(context);
            final boolean isSafeMode = manager.isSafeMode();

            // Make sure the default workspace is loaded, if needed
            mApp.getLauncherProvider().loadDefaultFavoritesIfNecessary(0, false);

            synchronized (sBgLock) {
                sBgWorkspaceItems.clear();
                sBgAppWidgets.clear();
                sBgFolders.clear();
                sBgItemsIdMap.clear();
                sBgDbIconCache.clear();

                final ArrayList<Long> itemsToRemove = new ArrayList<Long>();

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

                // +1 for the hotseat (it can be larger than the workspace)
                // Load workspace in reverse order to ensure that latest items are loaded first (and
                // before any earlier duplicates)
                final ItemInfo occupied[][][] =
                        new ItemInfo[Launcher.SCREEN_COUNT + 1][mCellCountX + 1][mCellCountY + 1];

                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 profileIdIndex = c.getColumnIndexOrThrow(
                            LauncherSettings.Favorites.PROFILE_ID);
                    //final int uriIndex = c.getColumnIndexOrThrow(LauncherSettings.Favorites.URI);
                    //final int displayModeIndex = c.getColumnIndexOrThrow(
                    //        LauncherSettings.Favorites.DISPLAY_MODE);

                    ShortcutInfo info;
                    String intentDescription;
                    LauncherAppWidgetInfo appWidgetInfo;
                    int container;
                    long id;
                    Intent intent;
                    UserHandle user;

                    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);
                                int serialNumber = c.getInt(profileIdIndex);
                                user = mUserManager.getUserForSerialNumber(serialNumber);
                                // If the user doesn't exist anymore, skip.
                                if (user == null) {
                                    itemsToRemove.add(c.getLong(idIndex));
                                    continue;
                                }
                                try {
                                    intent = Intent.parseUri(intentDescription, 0);
                                } catch (URISyntaxException e) {
                                    continue;
                                }

                                if (itemType == LauncherSettings.Favorites.ITEM_TYPE_APPLICATION) {
                                        info = getShortcutInfo(
                                                manager, intent, user, context, c, iconIndex,
                                            titleIndex, mLabelCache);
                                } else {
                                    info = getShortcutInfo(c, context, iconTypeIndex,
                                            iconPackageIndex, iconResourceIndex, iconIndex,
                                            titleIndex);

                                    // App shortcuts that used to be automatically added to Launcher
                                    // didn't always have the correct intent flags set, so do that
                                    // here
                                    if (intent.getAction() != null &&
                                        intent.getCategories() != null &&
                                        intent.getAction().equals(Intent.ACTION_MAIN) &&
                                        intent.getCategories().contains(Intent.CATEGORY_LAUNCHER)) {
                                        intent.addFlags(
                                            Intent.FLAG_ACTIVITY_NEW_TASK |
                                            Intent.FLAG_ACTIVITY_RESET_TASK_IF_NEEDED);
                                    }
                                }

                                if (info != null) {
                                    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);
                                    info.intent.putExtra(ItemInfo.EXTRA_PROFILE, info.user);

                                    // check & update map of what's occupied
                                    if (!checkItemPlacement(occupied, info)) {
                                        break;
                                    }

                                    switch (container) {
                                    case LauncherSettings.Favorites.CONTAINER_DESKTOP:
                                    case LauncherSettings.Favorites.CONTAINER_HOTSEAT:
                                        sBgWorkspaceItems.add(info);
                                        break;
                                    default:
                                        // Item is in a user folder
                                        FolderInfo folderInfo =
                                                findOrMakeFolder(sBgFolders, container);
                                        folderInfo.add(info);
                                        break;
                                    }
                                    sBgItemsIdMap.put(info.id, info);

                                    // now that we've loaded everthing re-save it with the
                                    // icon in case it disappears somehow.
                                    queueIconToBeChecked(sBgDbIconCache, info, c, iconIndex);
                                } else {
                                    // Failed to load the shortcut, probably because the
                                    // activity manager couldn't resolve it (maybe the app
                                    // was uninstalled), or the db row was somehow screwed up.
                                    // Delete it.
                                    id = c.getLong(idIndex);
                                    Log.e(TAG, "Error loading shortcut " + id + ", removing it");
                                    contentResolver.delete(LauncherSettings.Favorites.getContentUri(
                                                id, false), null, null);
                                }
                                break;

                            case LauncherSettings.Favorites.ITEM_TYPE_FOLDER:
                                id = c.getLong(idIndex);
                                FolderInfo folderInfo = findOrMakeFolder(sBgFolders, 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);

                                // check & update map of what's occupied
                                if (!checkItemPlacement(occupied, folderInfo)) {
                                    break;
                                }
                                switch (container) {
                                    case LauncherSettings.Favorites.CONTAINER_DESKTOP:
                                    case LauncherSettings.Favorites.CONTAINER_HOTSEAT:
                                        sBgWorkspaceItems.add(folderInfo);
                                        break;
                                }

                                sBgItemsIdMap.put(folderInfo.id, folderInfo);
                                sBgFolders.put(folderInfo.id, folderInfo);
                                break;

                            case LauncherSettings.Favorites.ITEM_TYPE_APPWIDGET:
                                // Read all Launcher-specific widget details
                                int appWidgetId = c.getInt(appWidgetIdIndex);
                                id = c.getLong(idIndex);

                                final AppWidgetProviderInfo provider =
                                        widgets.getAppWidgetInfo(appWidgetId);

                                if (!isSafeMode && (provider == null || provider.provider == null ||
                                        provider.provider.getPackageName() == null)) {
                                    String log = "Deleting widget that isn't installed anymore: id="
                                        + id + " appWidgetId=" + appWidgetId;
                                    Log.e(TAG, log);
                                    Launcher.sDumpLogs.add(log);
                                    itemsToRemove.add(id);
                                } else {
                                    appWidgetInfo = new LauncherAppWidgetInfo(appWidgetId,
                                            provider.provider);
                                    appWidgetInfo.id = id;
                                    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);
                                    int[] minSpan = Launcher.getMinSpanForWidget(context, provider);
                                    appWidgetInfo.minSpanX = minSpan[0];
                                    appWidgetInfo.minSpanY = minSpan[1];

                                    container = c.getInt(containerIndex);
                                    if (container != LauncherSettings.Favorites.CONTAINER_DESKTOP &&
                                        container != LauncherSettings.Favorites.CONTAINER_HOTSEAT) {
                                        Log.e(TAG, "Widget found where container != " +
                                            "CONTAINER_DESKTOP nor CONTAINER_HOTSEAT - ignoring!");
                                        continue;
                                    }
                                    appWidgetInfo.container = c.getInt(containerIndex);

                                    // check & update map of what's occupied
                                    if (!checkItemPlacement(occupied, appWidgetInfo)) {
                                        break;
                                    }
                                    sBgItemsIdMap.put(appWidgetInfo.id, appWidgetInfo);
                                    sBgAppWidgets.add(appWidgetInfo);
                                }
                                break;
                            }
                        } catch (Exception e) {
                            Log.w(TAG, "Desktop items loading interrupted:", e);
                        }
                    }
                } finally {
                    c.close();
                }

                if (itemsToRemove.size() > 0) {
                    ContentProviderClient client = contentResolver.acquireContentProviderClient(
                                    LauncherSettings.Favorites.CONTENT_URI);
                    // Remove dead items
                    for (long id : itemsToRemove) {
                        if (DEBUG_LOADERS) {
                            Log.d(TAG, "Removed id = " + id);
                        }
                        // Don't notify content observers
                        try {
                            client.delete(LauncherSettings.Favorites.getContentUri(id, false),
                                    null, null);
                        } catch (RemoteException e) {
                            Log.w(TAG, "Could not remove id = " + id);
                        }
                    }
                }

                if (DEBUG_LOADERS) {
                    Log.d(TAG, "loaded workspace in " + (SystemClock.uptimeMillis()-t) + "ms");
                    Log.d(TAG, "workspace layout: ");
                    for (int y = 0; y < mCellCountY; y++) {
                        String line = "";
                        for (int s = 0; s < Launcher.SCREEN_COUNT; s++) {
                            if (s > 0) {
                                line += " | ";
                            }
                            for (int x = 0; x < mCellCountX; x++) {
                                line += ((occupied[s][x][y] != null) ? "#" : ".");
                            }
                        }
                        Log.d(TAG, "[ " + line + " ]");
                    }
                }
            }
        }

mApp.getLauncherProvider().loadDefaultFavoritesIfNecessary(0, false); 从资源default_workspace.xml中读取默认的偏好到默认favorite数据库中，即初始化favorite,然后获取数据库信息解析分类加载到内存
看下初始化favorite

 private int loadFavorites(SQLiteDatabase db, int workspaceResourceId) {
            Intent intent = new Intent(Intent.ACTION_MAIN, null);
            intent.addCategory(Intent.CATEGORY_LAUNCHER);
            ContentValues values = new ContentValues();

            PackageManager packageManager = mContext.getPackageManager();
            int allAppsButtonRank =
                    mContext.getResources().getInteger(R.integer.hotseat_all_apps_index);
            int i = 0;
            try {
                XmlResourceParser parser = mContext.getResources().getXml(workspaceResourceId);
                AttributeSet attrs = Xml.asAttributeSet(parser);
                beginDocument(parser, TAG_FAVORITES);

                final int depth = parser.getDepth();

                int type;
                while (((type = parser.next()) != XmlPullParser.END_TAG ||
                        parser.getDepth() > depth) && type != XmlPullParser.END_DOCUMENT) {

                    if (type != XmlPullParser.START_TAG) {
                        continue;
                    }

                    boolean added = false;
                    final String name = parser.getName();

                    TypedArray a = mContext.obtainStyledAttributes(attrs, R.styleable.Favorite);

                    long container = LauncherSettings.Favorites.CONTAINER_DESKTOP;
                    if (a.hasValue(R.styleable.Favorite_container)) {
                        container = Long.valueOf(a.getString(R.styleable.Favorite_container));
                    }

                    String screen = a.getString(R.styleable.Favorite_screen);
                    String x = a.getString(R.styleable.Favorite_x);
                    String y = a.getString(R.styleable.Favorite_y);

                    // If we are adding to the hotseat, the screen is used as the position in the
                    // hotseat. This screen can't be at position 0 because AllApps is in the
                    // zeroth position.
                    if (container == LauncherSettings.Favorites.CONTAINER_HOTSEAT
                            && Integer.valueOf(screen) == allAppsButtonRank) {
                        throw new RuntimeException("Invalid screen position for hotseat item");
                    }

                    values.clear();
                    values.put(LauncherSettings.Favorites.CONTAINER, container);
                    values.put(LauncherSettings.Favorites.SCREEN, screen);
                    values.put(LauncherSettings.Favorites.CELLX, x);
                    values.put(LauncherSettings.Favorites.CELLY, y);

                    if (TAG_FAVORITE.equals(name)) {
                        long id = addAppShortcut(db, values, a, packageManager, intent);
                        added = id >= 0;
                    } else if (TAG_SEARCH.equals(name)) {
                        added = addSearchWidget(db, values);
                    } else if (TAG_CLOCK.equals(name)) {
                        added = addClockWidget(db, values);
                    } else if (TAG_APPWIDGET.equals(name)) {
                        added = addAppWidget(parser, attrs, type, db, values, a, packageManager);
                    } else if (TAG_SHORTCUT.equals(name)) {
                        long id = addUriShortcut(db, values, a);
                        added = id >= 0;
                    } else if (TAG_FOLDER.equals(name)) {
                        String title;
                        int titleResId =  a.getResourceId(R.styleable.Favorite_title, -1);
                        if (titleResId != -1) {
                            title = mContext.getResources().getString(titleResId);
                        } else {
                            title = mContext.getResources().getString(R.string.folder_name);
                        }
                        values.put(LauncherSettings.Favorites.TITLE, title);
                        long folderId = addFolder(db, values);
                        added = folderId >= 0;

                        ArrayList<Long> folderItems = new ArrayList<Long>();

                        int folderDepth = parser.getDepth();
                        while ((type = parser.next()) != XmlPullParser.END_TAG ||
                                parser.getDepth() > folderDepth) {
                            if (type != XmlPullParser.START_TAG) {
                                continue;
                            }
                            final String folder_item_name = parser.getName();

                            TypedArray ar = mContext.obtainStyledAttributes(attrs,
                                    R.styleable.Favorite);
                            values.clear();
                            values.put(LauncherSettings.Favorites.CONTAINER, folderId);

                            if (TAG_FAVORITE.equals(folder_item_name) && folderId >= 0) {
                                long id =
                                    addAppShortcut(db, values, ar, packageManager, intent);
                                if (id >= 0) {
                                    folderItems.add(id);
                                }
                            } else if (TAG_SHORTCUT.equals(folder_item_name) && folderId >= 0) {
                                long id = addUriShortcut(db, values, ar);
                                if (id >= 0) {
                                    folderItems.add(id);
                                }
                            } else {
                                throw new RuntimeException("Folders can " +
                                        "contain only shortcuts");
                            }
                            ar.recycle();
                        }
                        // We can only have folders with >= 2 items, so we need to remove the
                        // folder and clean up if less than 2 items were included, or some
                        // failed to add, and less than 2 were actually added
                        if (folderItems.size() < 2 && folderId >= 0) {
                            // We just delete the folder and any items that made it
                            deleteId(db, folderId);
                            if (folderItems.size() > 0) {
                                deleteId(db, folderItems.get(0));
                            }
                            added = false;
                        }
                    }
                    if (added) i++;
                    a.recycle();
                }
            } catch (XmlPullParserException e) {
                Log.w(TAG, "Got exception parsing favorites.", e);
            } catch (IOException e) {
                Log.w(TAG, "Got exception parsing favorites.", e);
            } catch (RuntimeException e) {
                Log.w(TAG, "Got exception parsing favorites.", e);
            }

            return i;
        }

需要解析default_workspace.xml内容如下：

<favorites xmlns:launcher="http://schemas.android.com/apk/res/com.android.launcher5">
    <!-- Far-left screen [0] -->

    <!-- Left screen [1] -->
    <appwidget
        launcher:packageName="com.android.settings"
        launcher:className="com.android.settings.widget.SettingsAppWidgetProvider"
        launcher:screen="1"
        launcher:x="0"
        launcher:y="3"
        launcher:spanX="4"
        launcher:spanY="1" />

    <!-- Middle screen [2] -->
    <appwidget
        launcher:packageName="com.android.deskclock"
        launcher:className="com.android.alarmclock.AnalogAppWidgetProvider"
        launcher:screen="2"
        launcher:x="1"
        launcher:y="0"
        launcher:spanX="2"
        launcher:spanY="2" />
    <favorite
        launcher:packageName="com.android.camera2"
        launcher:className="com.android.camera.CameraLauncher"
        launcher:screen="2"
        launcher:x="0"
        launcher:y="3" />

    <!-- Right screen [3] -->
    <favorite
        launcher:packageName="com.android.gallery3d"
        launcher:className="com.android.gallery3d.app.Gallery"
        launcher:screen="3"
        launcher:x="1"
        launcher:y="3" />
    <favorite
        launcher:packageName="com.android.settings"
        launcher:className="com.android.settings.Settings"
        launcher:screen="3"
        launcher:x="2"
        launcher:y="3" />

    <!-- Far-right screen [4] -->

    <!-- Hotseat (We use the screen as the position of the item in the hotseat) -->
    <favorite
        launcher:packageName="com.android.dialer"
        launcher:className="com.android.dialer.DialtactsActivity"
        launcher:container="-101"
        launcher:screen="0"
        launcher:x="0"
        launcher:y="0" />
    <favorite
        launcher:packageName="com.android.contacts"
        launcher:className="com.android.contacts.activities.PeopleActivity"
        launcher:container="-101"
        launcher:screen="1"
        launcher:x="1"
        launcher:y="0" />
    <favorite
        launcher:packageName="com.android.mms"
        launcher:className="com.android.mms.ui.ConversationList"
        launcher:container="-101"
        launcher:screen="3"
        launcher:x="3"
        launcher:y="0" />
    <favorite
        launcher:packageName="com.android.browser"
        launcher:className="com.android.browser.BrowserActivity"
        launcher:container="-101"
        launcher:screen="4"
        launcher:x="4"
        launcher:y="0" />
</favorites>

解析：

 <appwidget // widget
        launcher:packageName="com.android.settings" // pkg
        launcher:className="com.android.settings.widget.SettingsAppWidgetProvider" // 启动actName
        launcher:screen="1" //第几屏
        launcher:x="0" //行
        launcher:y="3" //列
        launcher:spanX="4" //x占格
        launcher:spanY="1" /> // y占格

 <favorite // 快捷方式
        launcher:packageName="com.android.browser"
        launcher:className="com.android.browser.BrowserActivity"
        launcher:container="-101"//底部快捷方式
        launcher:screen="4"
        launcher:x="4"
        launcher:y="0" />
//除了appwidget favorite 还有如下

　　　　　private static final String TAG_FAVORITES = "favorites";
        private static final String TAG_FAVORITE = "favorite";
        private static final String TAG_CLOCK = "clock";
        private static final String TAG_SEARCH = "search";
        private static final String TAG_APPWIDGET = "appwidget";
        private static final String TAG_SHORTCUT = "shortcut";
        private static final String TAG_FOLDER = "folder";
        private static final String TAG_EXTRA = "extra";

到此loadWorkspace()资源加载完。

workspace信息加载后分布如下几个集合中：

　　sBgItemsIdmap: 　　map<id,iteminfo>　　所有元素 包括 桌面快捷方式，底部栏快捷方式，文件夹，小控件

　　sBgWorkspaceItems: 　　List　　括 桌面快捷方式，底部栏快捷方式，

　　sBgAppWidgets:　　List　　小控件

　　sBgFolders:　　hashmap<folderId,folderItem>　　文件夹

 接下来研究绑定

 /**
         * Binds all loaded data to actual views on the main thread.
         */
        private void bindWorkspace(int synchronizeBindPage) {
            final long t = SystemClock.uptimeMillis();
            Runnable r;

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

            final boolean isLoadingSynchronously = (synchronizeBindPage > -1);
            final int currentScreen = isLoadingSynchronously ? synchronizeBindPage :
                oldCallbacks.getCurrentWorkspaceScreen();

            // Load all the items that are on the current page first (and in the process, unbind
            // all the existing workspace items before we call startBinding() below.
            unbindWorkspaceItemsOnMainThread();
            ArrayList<ItemInfo> workspaceItems = new ArrayList<ItemInfo>();
            ArrayList<LauncherAppWidgetInfo> appWidgets =
                    new ArrayList<LauncherAppWidgetInfo>();
            HashMap<Long, FolderInfo> folders = new HashMap<Long, FolderInfo>();
            HashMap<Long, ItemInfo> itemsIdMap = new HashMap<Long, ItemInfo>();
            synchronized (sBgLock) {
                workspaceItems.addAll(sBgWorkspaceItems);
                appWidgets.addAll(sBgAppWidgets);
                folders.putAll(sBgFolders);
                itemsIdMap.putAll(sBgItemsIdMap);
            }

            ArrayList<ItemInfo> currentWorkspaceItems = new ArrayList<ItemInfo>();
            ArrayList<ItemInfo> otherWorkspaceItems = new ArrayList<ItemInfo>();
            ArrayList<LauncherAppWidgetInfo> currentAppWidgets =
                    new ArrayList<LauncherAppWidgetInfo>();
            ArrayList<LauncherAppWidgetInfo> otherAppWidgets =
                    new ArrayList<LauncherAppWidgetInfo>();
            HashMap<Long, FolderInfo> currentFolders = new HashMap<Long, FolderInfo>();
            HashMap<Long, FolderInfo> otherFolders = new HashMap<Long, FolderInfo>();

            // Separate the items that are on the current screen, and all the other remaining items
            filterCurrentWorkspaceItems(currentScreen, workspaceItems, currentWorkspaceItems,
                    otherWorkspaceItems);
            filterCurrentAppWidgets(currentScreen, appWidgets, currentAppWidgets,
                    otherAppWidgets);
            filterCurrentFolders(currentScreen, itemsIdMap, folders, currentFolders,
                    otherFolders);
            sortWorkspaceItemsSpatially(currentWorkspaceItems);
            sortWorkspaceItemsSpatially(otherWorkspaceItems);

            // Tell the workspace that we're about to start binding items
            r = new Runnable() {
                public void run() {
                    Callbacks callbacks = tryGetCallbacks(oldCallbacks);
                    if (callbacks != null) {
                        callbacks.startBinding();
                    }
                }
            };
            runOnMainThread(r, MAIN_THREAD_BINDING_RUNNABLE);

            // Load items on the current page
            bindWorkspaceItems(oldCallbacks, currentWorkspaceItems, currentAppWidgets,
                    currentFolders, null);
            if (isLoadingSynchronously) {
                r = new Runnable() {
                    public void run() {
                        Callbacks callbacks = tryGetCallbacks(oldCallbacks);
                        if (callbacks != null) {
                            callbacks.onPageBoundSynchronously(currentScreen);
                        }
                    }
                };
                runOnMainThread(r, MAIN_THREAD_BINDING_RUNNABLE);
            }

            // Load all the remaining pages (if we are loading synchronously, we want to defer this
            // work until after the first render)
            mDeferredBindRunnables.clear();
            bindWorkspaceItems(oldCallbacks, otherWorkspaceItems, otherAppWidgets, otherFolders,
                    (isLoadingSynchronously ? mDeferredBindRunnables : null));

            // Tell the workspace that we're done binding items
            r = new Runnable() {
                public void run() {
                    Callbacks callbacks = tryGetCallbacks(oldCallbacks);
                    if (callbacks != null) {
                        callbacks.finishBindingItems();
                    }

                    // If we're profiling, ensure this is the last thing in the queue.
                    if (DEBUG_LOADERS) {
                        Log.d(TAG, "bound workspace in "
                            + (SystemClock.uptimeMillis()-t) + "ms");
                    }

                    mIsLoadingAndBindingWorkspace = false;
                }
            };
            if (isLoadingSynchronously) {
                mDeferredBindRunnables.add(r);
            } else {
                runOnMainThread(r, MAIN_THREAD_BINDING_RUNNABLE);
            }
        }

bindWorkspaceItems

绑定当前页面，绑定其他页

private void bindWorkspaceItems(final Callbacks oldCallbacks,
                final ArrayList<ItemInfo> workspaceItems,
                final ArrayList<LauncherAppWidgetInfo> appWidgets,
                final HashMap<Long, FolderInfo> folders,
                ArrayList<Runnable> deferredBindRunnables) {

            final boolean postOnMainThread = (deferredBindRunnables != null);

            // Bind the workspace items
            int N = workspaceItems.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);
                final Runnable r = new Runnable() {
                    @Override
                    public void run() {
                        Callbacks callbacks = tryGetCallbacks(oldCallbacks);
                        if (callbacks != null) {
                            callbacks.bindItems(workspaceItems, start, start+chunkSize);
                        }
                    }
                };
                if (postOnMainThread) {
                    deferredBindRunnables.add(r);
                } else {
                    runOnMainThread(r, MAIN_THREAD_BINDING_RUNNABLE);
                }
            }

            // Bind the folders
            if (!folders.isEmpty()) {
                final Runnable r = new Runnable() {
                    public void run() {
                        Callbacks callbacks = tryGetCallbacks(oldCallbacks);
                        if (callbacks != null) {
                            callbacks.bindFolders(folders);
                        }
                    }
                };
                if (postOnMainThread) {
                    deferredBindRunnables.add(r);
                } else {
                    runOnMainThread(r, MAIN_THREAD_BINDING_RUNNABLE);
                }
            }

            // Bind the widgets, one at a time
            N = appWidgets.size();
            for (int i = 0; i < N; i++) {
                final LauncherAppWidgetInfo widget = appWidgets.get(i);
                final Runnable r = new Runnable() {
                    public void run() {
                        Callbacks callbacks = tryGetCallbacks(oldCallbacks);
                        if (callbacks != null) {
                            callbacks.bindAppWidget(widget);
                        }
                    }
                };
                if (postOnMainThread) {
                    deferredBindRunnables.add(r);
                } else {
                    runOnMainThread(r, MAIN_THREAD_BINDING_RUNNABLE);
                }
            }
        }

　　

private static final int ITEMS_CHUNK = 6;

绑定顺序：

绑定快捷方式：callbacks.bindItems(workspaceItems, start, start+chunkSize);

绑定文件夹：callbacks.bindFolders(folders);

绑定小控件：callbacks.bindAppWidget(widget);

再下来研究具体绑定函数：Launcher。java 中的bindItems方式的实现

/**
     * Bind the items start-end from the list.
     *
     * Implementation of the method from LauncherModel.Callbacks.
     */
    public void bindItems(final ArrayList<ItemInfo> shortcuts, final int start, final int end) {
        if (waitUntilResume(new Runnable() {
                public void run() {
                    bindItems(shortcuts, start, end);
                }
            })) {
            return;
        }

        // Get the list of added shortcuts and intersect them with the set of shortcuts here
        Set<String> newApps = new HashSet<String>();
        newApps = mSharedPrefs.getStringSet(InstallShortcutReceiver.NEW_APPS_LIST_KEY, newApps);

        Workspace workspace = mWorkspace;
        for (int i = start; i < end; i++) {
            final ItemInfo item = shortcuts.get(i);

            // Short circuit if we are loading dock items for a configuration which has no dock
            if (item.container == LauncherSettings.Favorites.CONTAINER_HOTSEAT &&
                    mHotseat == null) {
                continue;
            }

            switch (item.itemType) {
                case LauncherSettings.Favorites.ITEM_TYPE_APPLICATION:
                case LauncherSettings.Favorites.ITEM_TYPE_SHORTCUT:
                    ShortcutInfo info = (ShortcutInfo) item;
                    String uri = info.intent.toUri(0).toString();
                    View shortcut = createShortcut(info);
                    workspace.addInScreen(shortcut, item.container, item.screen, item.cellX,
                            item.cellY, 1, 1, false);
                    boolean animateIconUp = false;
                    synchronized (newApps) {
                        if (newApps.contains(uri)) {
                            animateIconUp = newApps.remove(uri);
                        }
                    }
                    if (animateIconUp) {
                        // Prepare the view to be animated up
                        shortcut.setAlpha(0f);
                        shortcut.setScaleX(0f);
                        shortcut.setScaleY(0f);
                        mNewShortcutAnimatePage = item.screen;
                        if (!mNewShortcutAnimateViews.contains(shortcut)) {
                            mNewShortcutAnimateViews.add(shortcut);
                        }
                    }
                    break;
                case LauncherSettings.Favorites.ITEM_TYPE_FOLDER:
                    FolderIcon newFolder = FolderIcon.fromXml(R.layout.folder_icon, this,
                            (ViewGroup) workspace.getChildAt(workspace.getCurrentPage()),
                            (FolderInfo) item, mIconCache);
                    workspace.addInScreen(newFolder, item.container, item.screen, item.cellX,
                            item.cellY, 1, 1, false);
                    break;
            }
        }

        workspace.requestLayout();
    }

waitUntilResume函数暂不看 在pause情况下才执行
快捷方式和应用图标，文件夹生成相应View后加入workspace，具体如何加入view 待分析自定义workspace控件再看。
mNewShortcutAnimateViews 在绑定完成后统一执行动画显示 如下：

public void finishBindingItems() {
        if (waitUntilResume(new Runnable() {
                public void run() {
                    finishBindingItems();
                }
            })) {
            return;
        }
        if (mSavedState != null) {
            if (!mWorkspace.hasFocus()) {
                mWorkspace.getChildAt(mWorkspace.getCurrentPage()).requestFocus();
            }
            mSavedState = null;
        }

        mWorkspace.restoreInstanceStateForRemainingPages();

        // If we received the result of any pending adds while the loader was running (e.g. the
        // widget configuration forced an orientation change), process them now.
        for (int i = 0; i < sPendingAddList.size(); i++) {
            completeAdd(sPendingAddList.get(i));
        }
        sPendingAddList.clear();

        // Update the market app icon as necessary (the other icons will be managed in response to
        // package changes in bindSearchablesChanged()
        updateAppMarketIcon();

        // Animate up any icons as necessary
        if (mVisible || mWorkspaceLoading) {
            Runnable newAppsRunnable = new Runnable() {
                @Override
                public void run() {
                    runNewAppsAnimation(false);
                }
            };

            boolean willSnapPage = mNewShortcutAnimatePage > -1 &&
                    mNewShortcutAnimatePage != mWorkspace.getCurrentPage();
            if (canRunNewAppsAnimation()) {
                // If the user has not interacted recently, then either snap to the new page to show
                // the new-apps animation or just run them if they are to appear on the current page
                if (willSnapPage) {
                    mWorkspace.snapToPage(mNewShortcutAnimatePage, newAppsRunnable);
                } else {
                    runNewAppsAnimation(false);
                }
            } else {
                // If the user has interacted recently, then just add the items in place if they
                // are on another page (or just normally if they are added to the current page)
                runNewAppsAnimation(willSnapPage);
            }
        }

        mWorkspaceLoading = false;
    }

 /**
     * Runs a new animation that scales up icons that were added while Launcher was in the
     * background.
     *
     * @param immediate whether to run the animation or show the results immediately
     */
    private void runNewAppsAnimation(boolean immediate) {
        AnimatorSet anim = LauncherAnimUtils.createAnimatorSet();
        Collection<Animator> bounceAnims = new ArrayList<Animator>();

        // Order these new views spatially so that they animate in order
        Collections.sort(mNewShortcutAnimateViews, new Comparator<View>() {
            @Override
            public int compare(View a, View b) {
                CellLayout.LayoutParams alp = (CellLayout.LayoutParams) a.getLayoutParams();
                CellLayout.LayoutParams blp = (CellLayout.LayoutParams) b.getLayoutParams();
                int cellCountX = LauncherModel.getCellCountX();
                return (alp.cellY * cellCountX + alp.cellX) - (blp.cellY * cellCountX + blp.cellX);
            }
        });

        // Animate each of the views in place (or show them immediately if requested)
        if (immediate) {
            for (View v : mNewShortcutAnimateViews) {
                v.setAlpha(1f);
                v.setScaleX(1f);
                v.setScaleY(1f);
            }
        } else {
            for (int i = 0; i < mNewShortcutAnimateViews.size(); ++i) {
                View v = mNewShortcutAnimateViews.get(i);
                ValueAnimator bounceAnim = LauncherAnimUtils.ofPropertyValuesHolder(v,
                        PropertyValuesHolder.ofFloat("alpha", 1f),
                        PropertyValuesHolder.ofFloat("scaleX", 1f),
                        PropertyValuesHolder.ofFloat("scaleY", 1f));
                bounceAnim.setDuration(InstallShortcutReceiver.NEW_SHORTCUT_BOUNCE_DURATION);
                bounceAnim.setStartDelay(i * InstallShortcutReceiver.NEW_SHORTCUT_STAGGER_DELAY);
                bounceAnim.setInterpolator(new SmoothPagedView.OvershootInterpolator());
                bounceAnims.add(bounceAnim);
            }
            anim.playTogether(bounceAnims);
            anim.addListener(new AnimatorListenerAdapter() {
                @Override
                public void onAnimationEnd(Animator animation) {
                    if (mWorkspace != null) {
                        mWorkspace.postDelayed(mBuildLayersRunnable, 500);
                    }
                }
            });
            anim.start();
        }

        // Clean up
        mNewShortcutAnimatePage = -1;
        mNewShortcutAnimateViews.clear();
        new Thread("clearNewAppsThread") {
            public void run() {
                mSharedPrefs.edit()
                            .putInt(InstallShortcutReceiver.NEW_APPS_PAGE_KEY, -1)
                            .putStringSet(InstallShortcutReceiver.NEW_APPS_LIST_KEY, null)
                            .commit();
            }
        }.start();
    }

自此bindWorkspaceItems（）完结

则loadAndBindWorkspace()方法是加载和绑定桌面资源 (从资源文件和旧偏好)

开始分析  loadAndBindAllApps（）桌面绑定app信息

     private void loadAndBindAllApps() {
            if (DEBUG_LOADERS) {
                Log.d(TAG, "loadAndBindAllApps mAllAppsLoaded=" + mAllAppsLoaded);
            }
            if (!mAllAppsLoaded) {
                loadAllAppsByBatch();
                synchronized (LoaderTask.this) {
                    if (mStopped) {
                        return;
                    }
                    mAllAppsLoaded = true;
                }
            } else {
                onlyBindAllApps();
            }
        }

如上 执行loadAllAppsByBatch();

private void loadAllAppsByBatch() {
            final long t = DEBUG_LOADERS ? SystemClock.uptimeMillis() : 0;

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

            final Intent mainIntent = new Intent(Intent.ACTION_MAIN, null);
            mainIntent.addCategory(Intent.CATEGORY_LAUNCHER);

            final List<UserHandle> profiles = mUserManager.getUserProfiles();

            mBgAllAppsList.clear();
            final int profileCount = profiles.size();
            for (int p = 0; p < profileCount; p++) {
                UserHandle user = profiles.get(p);
                List<LauncherActivityInfo> apps = null;
                int N = Integer.MAX_VALUE;

                int startIndex;
                int i = 0;
                int batchSize = -1;
                while (i < N && !mStopped) {
                    if (i == 0) {
                        final long qiaTime = DEBUG_LOADERS ? SystemClock.uptimeMillis() : 0;
                        apps = mLauncherApps.getActivityList(null, user);
                        if (DEBUG_LOADERS) {
                            Log.d(TAG, "queryIntentActivities took "
                                    + (SystemClock.uptimeMillis()-qiaTime) + "ms");
                        }
                        if (apps == null) {
                            return;
                        }
                        N = apps.size();
                        if (DEBUG_LOADERS) {
                            Log.d(TAG, "queryIntentActivities got " + N + " apps");
                        }
                        if (N == 0) {
                            // There are no apps?!?
                            return;
                        }
                        if (mBatchSize == 0) {
                            batchSize = N;
                        } else {
                            batchSize = mBatchSize;
                        }

                        final long sortTime = DEBUG_LOADERS ? SystemClock.uptimeMillis() : 0;
                        Collections.sort(apps,
                                new LauncherModel.ShortcutNameComparator(mLabelCache));
                        if (DEBUG_LOADERS) {
                            Log.d(TAG, "sort took "
                                    + (SystemClock.uptimeMillis()-sortTime) + "ms");
                        }
                    }

                    final long t2 = DEBUG_LOADERS ? SystemClock.uptimeMillis() : 0;

                    startIndex = i;
                    for (int j=0; i<N && j<batchSize; j++) {
                        // This builds the icon bitmaps.
                        mBgAllAppsList.add(new ApplicationInfo(apps.get(i), user,
                                mIconCache, mLabelCache));
                        i++;
                    }

                    final Callbacks callbacks = tryGetCallbacks(oldCallbacks);
                    final ArrayList<ApplicationInfo> added = mBgAllAppsList.added;
                    final boolean firstProfile = p == 0;
                    mBgAllAppsList.added = new ArrayList<ApplicationInfo>();
                    mHandler.post(new Runnable() {
                        public void run() {
                            final long t = SystemClock.uptimeMillis();
                            if (callbacks != null) {
                                if (firstProfile) {
                                    callbacks.bindAllApplications(added);
                                } else {
                                    callbacks.bindAppsAdded(added);
                                }
                                if (DEBUG_LOADERS) {
                                    Log.d(TAG, "bound " + added.size() + " apps in "
                                        + (SystemClock.uptimeMillis() - t) + "ms");
                                }
                            } else {
                                Log.i(TAG, "not binding apps: no Launcher activity");
                            }
                        }
                    });

                    if (DEBUG_LOADERS) {
                        Log.d(TAG, "batch of " + (i-startIndex) + " icons processed in "
                                + (SystemClock.uptimeMillis()-t2) + "ms");
                    }

                    if (mAllAppsLoadDelay > 0 && i < N) {
                        try {
                            if (DEBUG_LOADERS) {
                                Log.d(TAG, "sleeping for " + mAllAppsLoadDelay + "ms");
                            }
                            Thread.sleep(mAllAppsLoadDelay);
                        } catch (InterruptedException exc) { }
                    }
                }

                if (DEBUG_LOADERS) {
                    Log.d(TAG, "cached all " + N + " apps in "
                            + (SystemClock.uptimeMillis()-t) + "ms"
                            + (mAllAppsLoadDelay > 0 ? " (including delay)" : ""));
                }
            }
        }

 apps = mLauncherApps.getActivityList(null, user);

mBgAllAppsList.add(new ApplicationInfo(apps.get(i), user,
mIconCache, mLabelCache));

mBgAllAppsList 为所有app 

回调 Laucher.java 中 callbacks.bindAllApplications(added);方法

 /**
     * Add the icons for all apps.
     *
     * Implementation of the method from LauncherModel.Callbacks.
     */
    public void bindAllApplications(final ArrayList<ApplicationInfo> apps) {
        Runnable setAllAppsRunnable = new Runnable() {
            public void run() {
                if (mAppsCustomizeContent != null) {
                    mAppsCustomizeContent.setApps(apps);
                }
            }
        };

        // Remove the progress bar entirely; we could also make it GONE
        // but better to remove it since we know it's not going to be used
        View progressBar = mAppsCustomizeTabHost.
            findViewById(R.id.apps_customize_progress_bar);
        if (progressBar != null) {
            ((ViewGroup)progressBar.getParent()).removeView(progressBar);

            // We just post the call to setApps so the user sees the progress bar
            // disappear-- otherwise, it just looks like the progress bar froze
            // which doesn't look great
            mAppsCustomizeTabHost.post(setAllAppsRunnable);
        } else {
            // If we did not initialize the spinner in onCreate, then we can directly set the
            // list of applications without waiting for any progress bars views to be hidden.
            setAllAppsRunnable.run();
        }
    }

AppsCustomizePagedView为所有app界面

mAppsCustomizeContent.setApps(apps);所有app数据表示绑定所有app界面完成

自此 loadAndBindAllApps（）桌面绑定app信息完结

即launcher资源加载全部完成了！

 参考了：http://blog.csdn.net/wdaming1986/article/details/7585649