how to make the bottomsheet drag expand high

[bobwatcherx]

I want to make a Dragable bottomsheet. When I drag it up, the height increases. and conversely, when I drag it down, the size of the height container decreases, I've made it however. even if it doesn't work, is there a way?

from flet import *


def main(page:Page):
	page.padding = 0 
	page.spacing = 0

	heightscr= page.window_height-270

	def on_updatemdl(e:DragUpdateEvent):
		ct.margin = margin.only(top=max(20,ct.height + e.delta_y))
		e.control.content.height = e.control.content.height + e.delta_y

		if e.delta_y > 0 :
			text.size = 40 
		else:
			text.size = 20 
		print(e.control.content.height)
		page.update()

	def hidemodal(e):
		gd.content.offset = transform.Offset(0,4)
		page.update()
	def showmodal(e):
		gd.content.offset = transform.Offset(0,0)
		page.update()

	text =  Text("i am bottom",size=20)
	ct = Container(
		bgcolor="yellow",
		margin=margin.only(top=page.window_height-270),
		width=page.window_width,
		height=heightscr,
		padding=30,
		content=Column([
			text,
			ElevatedButton("show",
		on_click=hidemodal
			),

			]),
		offset=transform.Offset(0,4),
		animate_offset=animation.Animation(600,curve="easeIn")
		)
	gd = GestureDetector(
		on_vertical_drag_update = on_updatemdl,
		content=ct,
		 drag_interval=10,

		)
	
	

	page.add(
		Stack([
		gd,

			ElevatedButton("show",
		on_click=showmodal
			),
				])
		)


flet.app(target=main)