Refactor get_bottom_toolbar implementation in getting_started.py example

.gitignore

@@ -63,3 +63,6 @@ package-lock.json
 
 # GitHub App credentials
 gha-creds-*.json
+
+# Superpowers extension
+docs/superpowers

GEMINI.md

@@ -13,6 +13,8 @@ Python project, which utilizes `uv` for environment and package management.
     - To run programs directly from a PyPI package (installing it on the fly if necessary), use
       `uvx ...` (shortcut for `uv tool run`).
 - **New Dependencies:** If a new dependency is required, please state the reason for its inclusion.
+- Do not commit spec, plan, or markdown documents to git without asking first.
+- Save plans to `~/.superpowers/plans/` instead of the project directory.
 
 ## Python Code Standards
 

examples/getting_started.py

@@ -1,5 +1,5 @@
 #!/usr/bin/env python3
-"""A simple example cmd2 application demonstrating many common features.
+"""An example cmd2 application demonstrating many common features.
 
 Features demonstrated include all of the following:
  1) Colorizing/stylizing output
@@ -15,11 +15,14 @@
 11) Shortcuts for commands
 12) Persistent bottom toolbar with realtime status updates
 13) Right prompt which displays contextual information
+14) Using a background thread to update the bottom toolbar in an efficient manner
+15) Using preloop() and postloop() hooks to start and stop a background thread
 """
 
 import datetime
 import pathlib
 import sys
+import threading
 
 from prompt_toolkit.application import get_app
 from prompt_toolkit.formatted_text import AnyFormattedText
@@ -92,17 +95,50 @@ def __init__(self) -> None:
             )
         )
 
+        # Initialize background thread state for the bottom toolbar
+        self._toolbar_state = {"now": ""}
+        self._toolbar_lock = threading.Lock()
+        self._stop_thread_event = threading.Event()
+        self._toolbar_thread: threading.Thread | None = None
+
+    def _update_toolbar_state(self) -> None:
+        """Background thread worker to update toolbar state continuously."""
+        while not self._stop_thread_event.is_set():
+            # Get the current time in ISO format with 0.01s precision
+            dt = datetime.datetime.now(datetime.timezone.utc).astimezone()
+            now = dt.strftime("%Y-%m-%dT%H:%M:%S.%f")[:-4] + dt.strftime("%z")
+
+            with self._toolbar_lock:
+                self._toolbar_state["now"] = now
+
+            # Sleep to yield CPU, polling 4 times a second
+            self._stop_thread_event.wait(0.25)
+
+    def preloop(self) -> None:
+        """Hook method executed once when the cmdloop() method is called."""
+        super().preloop()
+        self._stop_thread_event.clear()
+        self._toolbar_thread = threading.Thread(target=self._update_toolbar_state, daemon=True)
+        self._toolbar_thread.start()
+
+    def postloop(self) -> None:
+        """Hook method executed once when the cmdloop() method is about to return."""
+        super().postloop()
+        if self._toolbar_thread and self._toolbar_thread.is_alive():
+            self._stop_thread_event.set()
+            self._toolbar_thread.join()
+
     def get_bottom_toolbar(self) -> AnyFormattedText:
-        # Get the current time in ISO format with 0.01s precision
-        dt = datetime.datetime.now(datetime.timezone.utc).astimezone()
-        now = dt.strftime("%Y-%m-%dT%H:%M:%S.%f")[:-4] + dt.strftime("%z")
         left_text = sys.argv[0]
 
+        with self._toolbar_lock:
+            now = self._toolbar_state.get("now", "")
+
         # Fetch the terminal width to calculate padding for right-alignment.
         # If called outside a running app loop (e.g., in unit tests), get_app()
         # safely returns a dummy app with an 80-column fallback.
         cols = get_app().output.get_size().columns
-        padding_size = cols - len(left_text) - len(now) - 1
+        padding_size = cols - len(left_text) - len(now)
         if padding_size < 1:
             padding_size = 1
         padding = " " * padding_size