wxpython进度条由线程进行控制，为何没有滚动？

用threading控制wxpython的gauge的进度。
我在网上抄了一段代码，稍微改写了一下，运行的是，进度条不能滚动，这是为什么？请各位老师指点。

import wx
import threading
import time


class GaugeFrame(wx.Frame):
    def __init__(self):
        wx.Frame.__init__(self, None, -1, 'Gauge Example', size=(350, 150))
        panel = wx.Panel(self, -1)
        self.count = 0
        self.gauge = wx.Gauge(panel, -1, 50, (20, 50), (250, 25))
        self.gauge.SetBezelFace(3)
        self.gauge.SetShadowWidth(3)
        self.Bind(wx.EVT_IDLE, self.OnIdle)

    def OnIdle(self, event):
        self.gauge.SetValue(self.count)
        if self.count ==100:
            self.gauge.Destroy()

    def timer(self):
        while self.count < 100:
            self.count = self.count + 1
            time.sleep(2)


if __name__ == '__main__':
    app = wx.App()
    frame = GaugeFrame()
    frame.Show()
    threading.Thread(target=frame.timer())
    app.MainLoop()

https://blog.csdn.net/weixin_33922672/article/details/92292168