rpi_backlight.py 文件源码

def gui():
    """Start the graphical user interface."""
    try:
        import gi
        gi.require_version("Gtk", "3.0")
        from gi.repository import Gtk
    except ImportError:
        print("Sorry, this needs pygobject to be installed!")
        sys.exit()

    win = Gtk.Window(title="Set display brightness")

    ad1 = Gtk.Adjustment(value=get_actual_brightness(), lower=11, upper=255)
    scale = Gtk.Scale(orientation=Gtk.Orientation.HORIZONTAL, adjustment=ad1)

    def on_scale_changed(s, _):
        value = int(s.get_value())
        set_brightness(value)

    scale.connect("button-release-event", on_scale_changed)
    scale.connect("key_release_event", on_scale_changed)
    scale.connect("scroll-event", on_scale_changed)
    scale.set_size_request(350, 50)

    # Main Container
    main_container = Gtk.Fixed()
    main_container.put(scale, 10, 10)

    # Main Window
    win.connect("delete-event", Gtk.main_quit)
    win.connect("destroy", Gtk.main_quit)
    win.add(main_container)
    win.resize(400, 50)
    win.set_position(Gtk.WindowPosition.CENTER)

    win.show_all()
    Gtk.main()