Remember current directory for each volume.

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

Index: chrome/browser/resources/file_manager/js/file_manager.js
===================================================================
--- chrome/browser/resources/file_manager/js/file_manager.js	(revision 133417)
+++ chrome/browser/resources/file_manager/js/file_manager.js	(working copy)
@@ -768,10 +768,11 @@
       return self.renderRoot_(entry);
     };
 
-    this.rootsList_.selectionModel = this.directoryModel_.rootsListSelection;
+    this.rootsList_.selectionModel =
+        this.directoryModel_.getRootsListSelectionModel();
 
     // TODO(dgozman): add "Add a drive" item.
-    this.rootsList_.dataModel = this.directoryModel_.rootsList;
+    this.rootsList_.dataModel = this.directoryModel_.getRootsList();
     this.directoryModel_.updateRoots(function() {
         self.rootsList_.endBatchUpdates();
     }, false);
@@ -1117,8 +1118,7 @@
         return true;
 
       case 'format':
-        var entry =
-            this.getRootEntry_(this.rootsList_.selectionModel.selectedIndex);
+        var entry = this.directoryModel_.getCurrentRootDirEntry();
 
         return entry && DirectoryModel.getRootType(entry.fullPath) ==
                         DirectoryModel.RootType.REMOVABLE;
@@ -1407,16 +1407,11 @@
         return;
 
       case 'unmount':
-        var entry =
-            this.getRootEntry_(this.rootsList_.selectionModel.selectedIndex);
-
-        this.unmountVolume_(entry);
+        this.unmountVolume_(this.directoryModel_.getCurrentRootDirEntry());
         return;
 
       case 'format':
-        var entry =
-            this.getRootEntry_(this.rootsList_.selectionModel.selectedIndex);
-
+        var entry = this.directoryModel_.getCurrentRootDirEntry();
         this.confirm.show(str('FORMATTING_WARNING'), function() {
           chrome.fileBrowserPrivate.formatDevice(entry.toURL());
         });
@@ -1823,6 +1818,21 @@
     return path;
   };
 
+  /**
+   * Handler for root item being clicked.
+   * @private
+   * @param {Entry} entry Entry to navigate to.
+   * @param {Event} event The event.
+   */
+  FileManager.prototype.onRootClick_ = function(entry, event) {
+    var new_path = entry.fullPath;
+    if (entry.fullPath == this.directoryModel_.getCurrentRootPath()) {
+      this.directoryModel_.changeDirectory(entry.fullPath);

[SeRya, 2012/04/23 14:23:43]

I think this code would be much more clear:

dm.changeDirectory(dm.getActivePathForRoot(entry.fullPath))

(assuming changeDirectory handles errors and getActivePathForRoot returns last
selected directory or root itself).

[Oleg Eterevsky, 2012/04/23 14:33:04]

I don't see how will it make the code simpler. The 'if' here handles the case
when user clicks on the already active root. It has nothing to do with any
'active' directory for root.

+    } else {
+      this.directoryModel_.changeRoot(entry.fullPath);
+    }
+  };
+
   FileManager.prototype.renderRoot_ = function(entry) {
     var li = this.document_.createElement('li');
     li.className = 'root-item';
@@ -1874,18 +1884,6 @@
   };
 
   /**
-   * Handler for root item being clicked.
-   * @param {Entry} entry to navigate to.
-   * @param {Event} event The event.
-   */
-  FileManager.prototype.onRootClick_ = function(entry, event) {
-    var path = this.directoryModel_.currentEntry.fullPath;
-    if (path.indexOf(entry.fullPath) == 0 && path != entry.fullPath) {
-      this.directoryModel_.changeDirectory(entry.fullPath);
-    }
-  };
-
-  /**
    * Unmounts device.
    * @param {Entry} entry The entry to unmount.
    */
@@ -2387,7 +2385,8 @@
 
   FileManager.prototype.isOnGData = function() {
     return this.directoryModel_ &&
-        this.directoryModel_.rootPath == '/' + DirectoryModel.GDATA_DIRECTORY;
+        this.directoryModel_.getCurrentRootPath() ==
+            '/' + DirectoryModel.GDATA_DIRECTORY;
   };
 
   FileManager.prototype.getMetadataProvider = function() {
@@ -2649,7 +2648,7 @@
         } else if (this.isOnGData() &&
                    this.directoryModel_.currentEntry.unmounted) {
           // We are currently on an unmounted GData directory, force a rescan.
-          changeDirectoryTo = this.directoryModel_.rootPath;
+          changeDirectoryTo = this.directoryModel_.getCurrentRootPath();
         }
       } else {
         this.gdataMounted_ = false;
@@ -2695,7 +2694,7 @@
         }
 
         if (event.status == 'success' &&
-            event.mountPath == self.directoryModel_.rootPath) {
+            event.mountPath == self.directoryModel_.getCurrentRootPath()) {
           if (self.params_.mountTriggered && index == -1) {
             // This device mount was the reason this File Manager instance was
             // created. Now the device is unmounted from another instance
@@ -2847,7 +2846,7 @@
       // until we learn to save files directly to GData.
       var readonly = self.isOnReadonlyDirectory() || self.isOnGData();
       var currentDir = self.directoryModel_.currentEntry;
-      var downloadsDir = self.directoryModel_.rootsList.item(0);
+      var downloadsDir = self.directoryModel_.getRootsList().item(0);
 
       var context = {
         // We show the root label in readonly warning (e.g. archive name).
@@ -2883,7 +2882,7 @@
     var bc = this.dialogDom_.querySelector('.breadcrumbs');
     removeChildren(bc);
 
-    var rootPath = this.directoryModel_.rootPath;
+    var rootPath = this.directoryModel_.getCurrentRootPath();
     var relativePath = this.directoryModel_.currentEntry.fullPath.
                        substring(rootPath.length).replace(/\/$/, '');