有这样的代码：
from flet import *
import wget
def main(page: Page):
url = "https://drive.google.com/uc?export=download&confirm=no_antivirus&id=10Vov9B3KDNM7mnQ5e1WTyd2zbx3qmkf_"
def download():
btn_download_map.visible = False
btn_stop_download.visible = True
btn_download_map.update()
btn_stop_download.update()
wget.download(url = url, bar = progress)
btn_download_map.visible = True
btn_stop_download.visible = False
btn_download_map.update()
btn_stop_download.update()
def stop_download():
btn_download_map.visible = True
btn_stop_download.visible = False
btn_download_map.update()
btn_stop_download.update()
btn_download_map = ElevatedButton(
width = 200,
height = 50,
text = "Download",
on_click = lambda _: download()
)
btn_stop_download = ElevatedButton(
visible = False,
width = 200,
height = 50,
text = "Stop",
on_click = lambda _: stop_download()
)
def progress(current, total, width):
progress_bar.value = current / total
progress_bar.update()
tx_progress.value = f"{int(current / 1024)} KB / {int(total / 1024)} KB"
tx_progress.update()
tx_progress = Text(value = "", style = "headlineSmall")
progress_bar = ProgressBar(
width = 250
)
map_downloader = Container(
width = 300,
height = 250,
margin = 20,
padding = 10,
alignment = alignment.center,
border = border.all(5, "black"),
content = Column([
Column([
tx_progress,
progress_bar
]),
btn_download_map,
btn_stop_download
], alignment = MainAxisAlignment.CENTER, horizontal_alignment = CrossAxisAlignment.CENTER)
)
page.add(map_downloader)
if __name__ == "__main__":
app(target=main)
当我点击停止按钮时如何停止下载？