def slider_event_cb(e):
    code = e.get_code()
    obj = e.get_target_obj()

    # Provide some extra space for the value
    if code == lv.EVENT.REFR_EXT_DRAW_SIZE:
        e.set_ext_draw_size(50)

    elif code == lv.EVENT.DRAW_TASK_ADDED:
        dsc = e.get_draw_task()
        base_dsc = lv.draw_dsc_base_t.__cast__(dsc.draw_dsc)
        if base_dsc.part == lv.PART.INDICATOR:
            label_text = "{:d} - {:d}".format(obj.get_left_value(),slider.get_value())
            label_size = lv.point_t()
            lv.text_get_size(label_size, label_text, lv.font_default(), 0, 0, lv.COORD.MAX, 0)
            # print(label_size.x,label_size.y)
            label_area = lv.area_t()
            label_area.x1 = dsc.area.x1 + dsc.area.get_width() // 2 - label_size.x // 2
            label_area.x2 = label_area.x1 + label_size.x
            label_area.y2 = dsc.area.y1 - 10
            label_area.y1 = label_area.y2 - label_size.y

            label_draw_dsc = lv.draw_label_dsc_t()
            label_draw_dsc.init()
            label_draw_dsc.text = label_text
            label_draw_dsc.text_local = 1

            lv.draw_label(base_dsc.layer, label_draw_dsc, label_area)
#
# Show the current value when the slider if pressed by extending the drawer
#
#
#Create a slider in the center of the display

slider = lv.slider(lv.scr_act())
slider.center()

slider.set_mode(lv.slider.MODE.RANGE)
slider.set_value(70, lv.ANIM.OFF)
slider.set_left_value(20, lv.ANIM.OFF)

slider.add_event(slider_event_cb, lv.EVENT.ALL, None)
slider.add_flag(lv.obj.FLAG.SEND_DRAW_TASK_EVENTS)
slider.refresh_ext_draw_size()