from textual.app import App, ComposeResult from textual.containers import Center, Middle from textual.timer import Timer from textual.widgets import Footer, ProgressBar class IndeterminateProgressBar(App[None]): BINDINGS = [("s", "start", "Start")] progress_timer: Timer """Timer to simulate progress happening.""" def compose(self) -> ComposeResult: with Center(): with Middle(): yield ProgressBar() yield Footer() def on_mount(self) -> None: """Set up a timer to simulate progess happening.""" self.progress_timer = self.set_interval(1 / 10, self.make_progress, pause=True) def make_progress(self) -> None: """Called automatically to advance the progress bar.""" self.query_one(ProgressBar).advance(1) def action_start(self) -> None: """Start the progress tracking.""" self.query_one(ProgressBar).update(total=100) self.progress_timer.resume() if __name__ == "__main__": IndeterminateProgressBar().run()