more performance work for loading folders without .msf files or that have to have

headers downloaded.

mailnews/base/public/nsIMsgFolder.idl

@@ -51,6 +51,8 @@ interface nsIMsgFolder : nsIFolder {
   
 	nsISimpleEnumerator GetMessages();
 	nsISimpleEnumerator GetThreads();
+	void StartFolderLoading();
+	void EndFolderLoading();
 	/* get new headers for db */
 	void UpdateFolder();
 	nsIMsgThread GetThreadForMessage(in nsIMessage message);

mailnews/base/resources/content/commandglue.js

@@ -165,6 +165,7 @@ function ChangeFolderByURI(uri)
   {
 	try
 	{
+		msgfolder.StartFolderLoading();
 		msgfolder.UpdateFolder();
 	}
 	catch(ex)

mailnews/base/resources/content/msgMail3PaneWindow.js

@@ -76,7 +76,12 @@ var folderListener = {
 				{
 					var id = selArray[0].getAttribute('id');
 					if(uri == id)
+					{
+						var msgFolder = folder.QueryInterface(Components.interfaces.nsIMsgFolder);
+						if(msgFolder)
+							msgFolder.EndFolderLoading();
 						RerootFolder(uri);
+					}
 				}
 			}
 		}

mailnews/base/src/nsMsgFolderDataSource.cpp

@@ -80,9 +80,6 @@ nsMsgFolderDataSource::nsMsgFolderDataSource():
 nsMsgFolderDataSource::~nsMsgFolderDataSource (void)
 {
   nsresult rv;
-  nsIRDFService *rdf = getRDFService();
-  if(rdf)
-	rdf->UnregisterDataSource(this);
 
   NS_WITH_SERVICE(nsIMsgMailSession, mailSession, kMsgMailSessionCID, &rv); 
 	if(NS_SUCCEEDED(rv))

mailnews/base/util/nsMsgDBFolder.cpp

@@ -56,7 +56,7 @@ NS_IMETHODIMP nsMsgDBFolder::QueryInterface(REFNSIID aIID, void** aInstancePtr)
 }
 
 nsMsgDBFolder::nsMsgDBFolder(void)
-: mCharset("")
+: mCharset(""), mAddListener(PR_TRUE)
 {
 
 }
@@ -70,6 +70,22 @@ nsMsgDBFolder::~nsMsgDBFolder(void)
 	}
 }
 
+NS_IMETHODIMP nsMsgDBFolder::StartFolderLoading(void)
+{
+	if(mDatabase)
+		mDatabase->RemoveListener(this);
+	mAddListener = PR_FALSE;
+	return NS_OK;
+}
+
+NS_IMETHODIMP nsMsgDBFolder::EndFolderLoading(void)
+{
+	if(mDatabase)
+		mDatabase->AddListener(this);
+	mAddListener = PR_TRUE;
+	return NS_OK;
+}
+
 NS_IMETHODIMP nsMsgDBFolder::GetThreads(nsISimpleEnumerator** threadEnumerator)
 {
 	nsresult rv = GetDatabase();

mailnews/base/util/nsMsgDBFolder.h

@@ -41,6 +41,8 @@ public:
 	virtual ~nsMsgDBFolder(void);
   NS_DECL_NSIDBCHANGELISTENER
   
+	NS_IMETHOD  StartFolderLoading(void);
+	NS_IMETHOD  EndFolderLoading(void);
 	NS_IMETHOD GetThreads(nsISimpleEnumerator** threadEnumerator);
 	NS_IMETHOD GetThreadForMessage(nsIMessage *message, nsIMsgThread **thread);
 	NS_IMETHOD HasMessage(nsIMessage *message, PRBool *hasMessage);
@@ -68,6 +70,7 @@ protected:
 protected:
 	nsCOMPtr<nsIMsgDatabase> mDatabase;  
 	nsString mCharset;
+	PRBool mAddListener;
 
 
 };

mailnews/base/util/nsMsgFolder.cpp

@@ -276,6 +276,16 @@ nsMsgFolder::GetMessages(nsISimpleEnumerator* *result)
   return NS_ERROR_FAILURE;
 }
 
+NS_IMETHODIMP nsMsgFolder::StartFolderLoading(void)
+{
+	return NS_OK;
+}
+
+NS_IMETHODIMP nsMsgFolder::EndFolderLoading(void)
+{
+	return NS_OK;
+}
+
 NS_IMETHODIMP
 nsMsgFolder::UpdateFolder()
 {

mailnews/base/util/nsMsgFolder.h

@@ -95,6 +95,9 @@ public:
   NS_IMETHOD ReplaceElement(nsISupports* element, nsISupports* newElement);
   NS_IMETHOD GetVisibleSubFolders(nsIEnumerator* *result);
   NS_IMETHOD GetMessages(nsISimpleEnumerator* *result);
+  NS_IMETHOD  StartFolderLoading(void);
+  NS_IMETHOD  EndFolderLoading(void);
+
   NS_IMETHOD UpdateFolder();
 
   NS_IMETHOD GetThreads(nsISimpleEnumerator ** threadEnumerator);

mailnews/imap/src/nsImapMailFolder.cpp

@@ -397,7 +397,8 @@ nsresult nsImapMailFolder::GetDatabase()
 
 		if(mDatabase)
 		{
-			mDatabase->AddListener(this);
+			if(mAddListener)
+				mDatabase->AddListener(this);
 
 			// if we have to regenerate the folder, run the parser url.
 			if(folderOpen == NS_MSG_ERROR_FOLDER_SUMMARY_MISSING || folderOpen == NS_MSG_ERROR_FOLDER_SUMMARY_OUT_OF_DATE)
@@ -1279,7 +1280,7 @@ NS_IMETHODIMP nsImapMailFolder::UpdateImapMailboxInfo(
             return rv;
         if (!mDatabase) 
             return NS_ERROR_NULL_POINTER;
-        if (mDatabase)
+        if (mDatabase && mAddListener)
             mDatabase->AddListener(this);
     }
     if (aSpec->folderSelected)
@@ -1344,7 +1345,8 @@ NS_IMETHODIMP nsImapMailFolder::UpdateImapMailboxInfo(
 				SummaryChanged();
                 rv = NS_ERROR_UNEXPECTED;
                 if (mDatabase) {
-                    mDatabase->AddListener(this);
+					if(mAddListener)
+	                    mDatabase->AddListener(this);
                     rv = mDatabase->GetDBFolderInfo(getter_AddRefs(dbFolderInfo));
                 }
 			}

mailnews/local/src/nsLocalMailFolder.cpp

@@ -480,7 +480,8 @@ nsresult nsMsgLocalMailFolder::GetDatabase()
 		if(mDatabase)
 		{
 
-			mDatabase->AddListener(this);
+			if(mAddListener)
+				mDatabase->AddListener(this);
 
 			// if we have to regenerate the folder, run the parser url.
 			if(folderOpen == NS_MSG_ERROR_FOLDER_SUMMARY_MISSING || folderOpen == NS_MSG_ERROR_FOLDER_SUMMARY_OUT_OF_DATE)

mailnews/news/src/nsNewsFolder.cpp

@@ -364,7 +364,8 @@ nsresult nsMsgNewsFolder::GetDatabase()
 		}
 
 		if (mDatabase) {
-			rv = mDatabase->AddListener(this);
+			if(mAddListener)
+				rv = mDatabase->AddListener(this);
 		    nsresult rv;
 		    nsCOMPtr<nsINewsDatabase> db(do_QueryInterface(mDatabase, &rv));
 		    if (NS_FAILED(rv))