Remember current directory for each volume.

chrome/browser/resources/file_manager/js/directory_model.js

Index: chrome/browser/resources/file_manager/js/directory_model.js
===================================================================
--- chrome/browser/resources/file_manager/js/directory_model.js	(revision 133184)
+++ chrome/browser/resources/file_manager/js/directory_model.js	(working copy)
@@ -39,8 +39,13 @@
 
   this.rootsList_ = new cr.ui.ArrayDataModel([]);
   this.rootsListSelection_ = new cr.ui.ListSingleSelectionModel();
-  this.rootsListSelection_.addEventListener(
-      'change', this.onRootsSelectionChanged_.bind(this));
+  this.currentRootDirEntry_ = root;
+  /**
+   * A map root.fullPath -> currentDirectory.fullPath.
+   * @private
+   * @type {Object.<string, string>}
+   */
+  this.currentDirByRoot_ = {};
 
   // The map 'name' -> callback. Callbacks are function(entry) -> boolean.
   this.filters_ = {};
@@ -105,14 +110,6 @@
   },
 
   /**
-   * Top level Directories from user perspective.
-   * @type {cr.ui.ArrayDataModel}
-   */
-  get rootsList() {
-    return this.rootsList_;
-  },
-
-  /**
    * Selection in the rootsList.
    * @type {cr.ui.ListSingleSelectionModel}
    */
@@ -120,15 +117,6 @@
     return this.rootsListSelection_;
   },
 
-  /**
-   * Root path for the current directory (parent directory is not navigatable
-   * for the user).
-   * @type {string}
-   */
-  get rootPath() {
-    return DirectoryModel.getRootPath(this.currentEntry.fullPath);
-  },
-
   get rootType() {
     return DirectoryModel.getRootType(this.currentEntry.fullPath);
   },
@@ -138,7 +126,7 @@
   },
 
   get rootEntry() {
-    return this.rootsList.item(this.rootsListSelection.selectedIndex);
+    return this.rootsList_.item(this.rootsListSelection.selectedIndex);
   },
 
   /**
@@ -249,6 +237,21 @@
 };

[Vladislav Kaznacheev, 2012/04/20 14:55:11]

nit: if you renamed these functions in place it would be easier for further
generations to look at the change history

[Oleg Eterevsky, 2012/04/20 15:00:32]

Unfortunately, they were defined as fields in

DirectoryModel.prototype = {
...
};

I had to move them out of this map literal to define them as proper methods.

 
 /**
+ * @return {cr.ui.ArrayDataModel} The list of roots.
+ */
+DirectoryModel.prototype.getRootsList = function() {
+  return this.rootsList_;
+};
+
+/**
+ * @return {string} Root path for the current directory (parent directory is
+ *     not navigatable for the user).
+ */
+DirectoryModel.prototype.getCurrentRootPath = function() {
+  return DirectoryModel.getRootPath(this.currentDirEntry_.fullPath);
+};
+
+/**
  * Add a filter for directory contents.
  * @param {string} name An identifier of the filter (used when removing it).
  * @param {function(Entry):boolean} filter Hide file if false.
@@ -329,8 +332,8 @@
 /**
  * @private
  * @param {Array.<Entry>|cr.ui.ArrayDataModel} list
- * @param {function} successCallback
- * @return {DirectoryModel.Scanner}
+ * @param {function} successCallback Callback on success.
+ * @return {DirectoryModel.Scanner} New Scanner instance.
  */
 DirectoryModel.prototype.createScanner_ = function(list, successCallback) {
   var self = this;
@@ -666,6 +669,7 @@
   this.updateVolumeMetadata_();
   this.updateRootsListSelection_();
   this.scan_(onRescanComplete);
+  this.currentDirByRoot_[this.getCurrentRootPath()] = dirEntry.fullPath;
 
   var e = new cr.Event('directory-changed');
   e.previousDirEntry = previous;
@@ -1001,10 +1005,8 @@
 */
 DirectoryModel.prototype.updateRoots = function(opt_callback,
                                                 opt_resolveGData) {
-  console.log('resolving roots');
   var self = this;
   this.resolveRoots_(function(rootEntries) {
-    console.log('resolved roots:', rootEntries);
     var dm = self.rootsList_;
     var args = [0, dm.length].concat(rootEntries);
     dm.splice.apply(dm, args);
@@ -1017,21 +1019,38 @@
 };
 
 /**
+ * Register a listener for a new root element in left menu.
  * @private
- * @param {Event} event
+ * @param {HTMLElement} li List item representing a volume.
+ * @param {Entry} entry Root directory entry.
  */
-DirectoryModel.prototype.onRootsSelectionChanged_ = function(event) {
-  var root = this.rootsList.item(this.rootsListSelection.selectedIndex);
-  if (root && this.rootPath != root.fullPath)
-    this.changeDirectory(root.fullPath);
+DirectoryModel.prototype.registerRootClickListener_ = function append(li,
+                                                                      entry) {
+  li.addEventListener('click', this.onRootClick_.bind(this, entry));
 };
 
 /**
+ * Handler for root item being clicked.
  * @private
+ * @param {Entry} entry Entry to navigate to.
+ * @param {Event} event The event.
  */
+DirectoryModel.prototype.onRootClick_ = function(entry, event) {
+  var new_path = entry.fullPath;
+  if (entry.fullPath == this.getCurrentRootPath()) {
+    this.changeDirectory(entry.fullPath);
+  } else {
+    this.changeDirectory(this.currentDirByRoot_[entry.fullPath] ||
+                         entry.fullPath);
+  }
+};
+
+/**
+ * @private
+ */
 DirectoryModel.prototype.updateRootsListSelection_ = function() {
   var roots = this.rootsList_;
-  var rootPath = this.rootPath;
+  var rootPath = this.getCurrentRootPath();
   for (var index = 0; index < roots.length; index++) {
     if (roots.item(index).fullPath == rootPath) {
       this.rootsListSelection.selectedIndex = index;
@@ -1068,7 +1087,7 @@
  * @private
  */
 DirectoryModel.prototype.updateVolumeMetadata_ = function() {
-  var rootPath = this.rootPath;
+  var rootPath = this.getCurrentRootPath();
   if (this.currentVolumeMetadata_.rootPath != rootPath) {
     var metadata = this.currentVolumeMetadata_ = {rootPath: rootPath};
     if (DirectoryModel.getRootType(rootPath) ==
@@ -1088,7 +1107,7 @@
 };
 
 /**
- * @param {string} path
+ * @param {string} path Any path in the file system.
  * @return {string} The root path.
  */
 DirectoryModel.getRootPath = function(path) {
@@ -1122,8 +1141,8 @@
 };
 
 /**
- * @param {string} path
- * @return {string}
+ * @param {string} path Path.
+ * @return {string} A root type.
  */
 DirectoryModel.getRootType = function(path) {
   function isTop(dir) {
@@ -1132,11 +1151,11 @@
 
   if (isTop(DirectoryModel.DOWNLOADS_DIRECTORY))
     return DirectoryModel.RootType.DOWNLOADS;
-  else if (isTop(DirectoryModel.GDATA_DIRECTORY))
+  if (isTop(DirectoryModel.GDATA_DIRECTORY))
     return DirectoryModel.RootType.GDATA;
-  else if (isTop(DirectoryModel.ARCHIVE_DIRECTORY))
+  if (isTop(DirectoryModel.ARCHIVE_DIRECTORY))
     return DirectoryModel.RootType.ARCHIVE;
-  else if (isTop(DirectoryModel.REMOVABLE_DIRECTORY))
+  if (isTop(DirectoryModel.REMOVABLE_DIRECTORY))
     return DirectoryModel.RootType.REMOVABLE;
   return '';
 };