v1.8.4: fix FilesTab showing stale remote files on server switch

- Clear remote panel immediately when switching servers
- Add race condition guards in async SFTP connect/refresh
- Validate alias at each async callback to prevent stale UI updates
- Add switching_servers/disconnected/sftp_server_not_found i18n keys
- Properly handle connection results arriving after server switch

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

core/i18n.py

@@ -277,6 +277,9 @@ _EN = {
     "items_count": "{count} items",
     "sudo_mode": "Sudo",
     "try_sudo_hint": "Try enabling Sudo mode",
+    "switching_servers": "Switching servers...",
+    "disconnected": "Disconnected",
+    "sftp_server_not_found": "[!] Server not found",
     "uploading_dir": "Uploading folder: {name}",
     "downloading_dir": "Downloading folder: {name}",
     "transfer_file_progress": "File {cur}/{total}: {name}",
@@ -539,6 +542,9 @@ _RU = {
     "items_count": "{count} элементов",
     "sudo_mode": "Sudo",
     "try_sudo_hint": "Попробуйте включить Sudo",
+    "switching_servers": "Переключение серверов...",
+    "disconnected": "Отключено",
+    "sftp_server_not_found": "[!] Сервер не найден",
     "uploading_dir": "Загрузка папки: {name}",
     "downloading_dir": "Скачивание папки: {name}",
     "transfer_file_progress": "Файл {cur}/{total}: {name}",
@@ -801,6 +807,9 @@ _ZH = {
     "items_count": "{count} 个项目",
     "sudo_mode": "Sudo",
     "try_sudo_hint": "尝试启用Sudo模式",
+    "switching_servers": "切换服务器...",
+    "disconnected": "已断开",
+    "sftp_server_not_found": "[!] 未找到服务器",
     "uploading_dir": "上传文件夹: {name}",
     "downloading_dir": "下载文件夹: {name}",
     "transfer_file_progress": "文件 {cur}/{total}: {name}",

gui/tabs/files_tab.py

@@ -283,6 +283,11 @@ class FilesTab(ctk.CTkFrame):
         if self._current_alias == alias:
             return
 
+        # Clear remote panel immediately to avoid showing stale files
+        self._remote_list.populate([])
+        self._remote_status.configure(text=t("switching_servers") if alias else t("connect_to_browse"))
+        self._set_remote_buttons_state("disabled")
+
         self._disconnect_sftp()
         self._current_alias = alias
 
@@ -304,22 +309,32 @@ class FilesTab(ctk.CTkFrame):
     def _connect_sftp(self):
         server = self.store.get_server(self._current_alias)
         if not server:
+            self._remote_status.configure(text=t("sftp_server_not_found"))
+            self._set_remote_buttons_state("disabled")
             return
+
+        # Capture current alias to prevent race condition when switching servers quickly
+        current_alias_at_call = self._current_alias
+
         self._remote_status.configure(text=t("connecting_sftp"))
         self._set_remote_buttons_state("disabled")
 
         def _do():
+            # Only proceed if we're still on the same server
+            if self._current_alias != current_alias_at_call:
+                return
+
             try:
                 # Use session pool if available
                 if self.session_pool:
                     sftp, is_new = self.session_pool.get_or_create_sftp_session(
-                        self._current_alias,
+                        current_alias_at_call,  # Use the original alias to avoid race conditions
                         server,
                         self.store.get_ssh_key_path()
                     )
 
                     # Get stored state
-                    stored_path, stored_sudo = self.session_pool.get_sftp_state(self._current_alias)
+                    stored_path, stored_sudo = self.session_pool.get_sftp_state(current_alias_at_call)
 
                     # Set sudo mode before connecting if it was stored
                     sftp.sudo_mode = stored_sudo
@@ -337,19 +352,36 @@ class FilesTab(ctk.CTkFrame):
                         except:
                             pass  # Fall back to normalized home path
 
-                    self.after(0, lambda: self._on_sftp_connected(sftp, home))
+                    # Final check before calling callback
+                    if self._current_alias == current_alias_at_call:
+                        self.after(0, lambda a=current_alias_at_call: self._on_sftp_connected(sftp, home, a))
                 else:
                     # Legacy behavior without session pool
                     sftp = SFTPSession(server, self.store.get_ssh_key_path())
                     sftp.connect()
                     home = sftp.normalize(".")
-                    self.after(0, lambda: self._on_sftp_connected(sftp, home))
+                    # Final check before calling callback
+                    if self._current_alias == current_alias_at_call:
+                        self.after(0, lambda a=current_alias_at_call: self._on_sftp_connected(sftp, home, a))
             except Exception as e:
+                # Only show error if still on the same server
+                if self._current_alias == current_alias_at_call:
                     self.after(0, lambda: self._on_sftp_error(str(e)))
 
         threading.Thread(target=_do, daemon=True).start()
 
-    def _on_sftp_connected(self, sftp: SFTPSession, home: str):
+    def _on_sftp_connected(self, sftp: SFTPSession, home: str, expected_alias: str):
+        # Only update UI if we're still on the same server that requested this connection
+        if self._current_alias != expected_alias:
+            # This connection result is from a server we've already switched away from
+            # If we're not using session pooling, disconnect this session
+            if not self.session_pool:
+                try:
+                    sftp.disconnect()
+                except:
+                    pass
+            return
+
         self._sftp = sftp
         # Update sudo var to match the restored session state
         self._sudo_var.set(self._sftp.sudo_mode)
@@ -367,6 +399,11 @@ class FilesTab(ctk.CTkFrame):
         self._log_msg(t("sftp_error").format(e=error))
 
     def _disconnect_sftp(self):
+        # Clear the remote display immediately
+        self._remote_list.populate([])
+        self._remote_status.configure(text=t("disconnected"))
+        self._set_remote_buttons_state("disabled")
+
         # Only disconnect if not using session pool (otherwise session stays alive)
         if self._sftp and not self.session_pool:
             try:
@@ -374,9 +411,8 @@ class FilesTab(ctk.CTkFrame):
             except Exception:
                 pass
             self._sftp = None
-        # If using session pool, remove callbacks to prevent processing data after switch
+        # If using session pool, just clear our reference to prevent interaction with old session
         elif self._sftp and self.session_pool:
-            # Don't actually disconnect, just remove the reference to avoid further interaction
             self._sftp = None
 
     # ── Browse / Drive ──
@@ -478,6 +514,9 @@ class FilesTab(ctk.CTkFrame):
         self._remote_path_entry.delete(0, "end")
         self._remote_path_entry.insert(0, self._remote_path)
 
+        # Capture current server alias to prevent race condition when switching servers
+        current_alias_at_call = self._current_alias
+
         def _list_remote():
             """Fetch remote listing, returns items list."""
             if self._sftp.sudo_mode:
@@ -504,6 +543,10 @@ class FilesTab(ctk.CTkFrame):
             return items
 
         def _do():
+            # Check if we're still on the same server after async operations
+            if self._current_alias != current_alias_at_call:
+                return  # Cancel if server has changed
+
             # Ensure connection is alive, reconnect if needed
             if not self._sftp.connected:
                 try:
@@ -515,19 +558,36 @@ class FilesTab(ctk.CTkFrame):
                     self.after(0, lambda: self._on_sftp_error("Reconnect failed"))
                     return
 
+            # Final check if server changed during connection attempt
+            if self._current_alias != current_alias_at_call:
+                return  # Cancel if server has changed
+
             try:
                 items = _list_remote()
+                # Final check before updating UI
+                if self._current_alias == current_alias_at_call:
                     self.after(0, lambda: self._populate_remote(items))
             except PermissionError as e:
+                if self._current_alias == current_alias_at_call:
                     hint = f"\n{t('try_sudo_hint')}" if not self._sftp.sudo_mode else ""
                     self.after(0, lambda: self._on_sftp_error(str(e) + hint))
             except Exception:
+                # Final check before attempting reconnect
+                if self._current_alias != current_alias_at_call:
+                    return  # Cancel if server has changed
+
                 # Operation failed — one reconnect attempt
                 try:
                     self._sftp.reconnect()
+
+                    # Final check after reconnection attempt
+                    if self._current_alias != current_alias_at_call:
+                        return  # Cancel if server has changed
+
                     items = _list_remote()
                     self.after(0, lambda: self._populate_remote(items))
                 except Exception as e2:
+                    if self._current_alias == current_alias_at_call:
                         self.after(0, lambda: self._on_sftp_error(str(e2)))
 
         threading.Thread(target=_do, daemon=True).start()

version.py

@@ -1,6 +1,6 @@
 """Version info for ServerManager."""
 
-__version__ = "1.8.3"
+__version__ = "1.8.4"
 __app_name__ = "ServerManager"
 __author__ = "aibot777"
 __description__ = "Desktop GUI for managing remote servers"