base.py 文件源码

def __enter__(self):
        # Create UI Application.
        title_toolbar = ConditionalContainer(
            Window(FormattedTextControl(lambda: self.title), height=1, style='class:progressbar,title'),
            filter=Condition(lambda: self.title is not None))

        bottom_toolbar = ConditionalContainer(
            Window(FormattedTextControl(lambda: self.bottom_toolbar,
                                        style='class:bottom-toolbar.text'),
                   style='class:bottom-toolbar',
                   height=1),
            filter=~is_done & renderer_height_is_known &
                Condition(lambda: self.bottom_toolbar is not None))

        def width_for_formatter(formatter):
            return formatter.get_width(progress_bar=self)

        progress_controls = [
            Window(content=_ProgressControl(self, f), width=width_for_formatter(f))
            for f in self.formatters
        ]

        self.app = Application(
            min_redraw_interval=.05,
            layout=Layout(HSplit([
                title_toolbar,
                VSplit(progress_controls,
                       height=lambda: D(
                           preferred=len(self.counters),
                           max=len(self.counters))),
                Window(),
                bottom_toolbar,
            ])),
            style=self.style,
            key_bindings=self.key_bindings,
            output=self.output,
            input=self.input)

        # Run application in different thread.
        def run():
            with _auto_refresh_context(self.app, .3):
                try:
                    self.app.run()
                except Exception as e:
                    traceback.print_exc()
                    print(e)

        self._thread = threading.Thread(target=run)
        self._thread.start()

        # Attach WINCH signal handler in main thread.
        # (Interrupt that we receive during resize events.)
        self._has_sigwinch = hasattr(signal, 'SIGWINCH') and in_main_thread()
        if self._has_sigwinch:
            self._previous_winch_handler = self._loop.add_signal_handler(
                signal.SIGWINCH, self.app.invalidate)

        return self