Wxpython背景莫名消失

WXPython Python 3.10
我想要为我的窗口添加背景(在网上找了代码),但开始挺成功,但我想要显示文本时,背景不见了.
控制台没有报错

img

我觉得他应该没有错误

import wx

class StartFrame(wx.Frame):

    def __init__(self, parent=None, ID=-1):
        super().__init__(parent, title="ServerNet v0.1 By Jemods.",
                         size=(1440, 900), pos=(100, 20), id=ID)
        self.panel = wx.Panel(self)
        self.panel.Bind(wx.EVT_ERASE_BACKGROUND, self.OnEraseBack)
        font = wx.Font(30, wx.DEFAULT, wx.NORMAL, wx.BOLD, faceName="Minecraft AE")
        text = TransparentText(self, -1 , "hi", style=wx.ALIGN_CENTER)
        text.SetForegroundColour('blue')
        text.SetFont(font)


    def OnEraseBack(self, event):
        dc = event.GetDC()
        if not dc:
            dc = wx.ClientDC(self)
            rect = self.GetUpdateRegion().GetBox()
            dc.SetClippingRect(rect)
        dc.Clear()
        bmp = wx.Bitmap("resources/back.jpg")
        dc.DrawBitmap(bmp, 0, 0)

class TransparentText(wx.StaticText):#继承了wx.Statictext的类，并对相应的方法进行重写;
    def __init__(self, parent, id=wx.ID_ANY, label='', pos=wx.DefaultPosition, size=wx.DefaultSize, style=wx.TRANSPARENT_WINDOW, name='transparenttext'):
        wx.StaticText.__init__(self, parent, id, label, pos, size, style, name)
        self.Bind(wx.EVT_PAINT, self.on_paint)
        self.Bind(wx.EVT_ERASE_BACKGROUND, lambda event: None)
        self.Bind(wx.EVT_SIZE, self.on_size)
    def on_paint(self, event):#重写on_paint可以对控件进行重写重新构造形状
        bdc = wx.PaintDC(self)
        dc = wx.GCDC(bdc)
        font_face = self.GetFont()
        font_color = self.GetForegroundColour()
        dc.SetFont(font_face)
        dc.SetTextForeground(font_color)
        dc.DrawText(self.GetLabel(), 0, 0)
    def on_size(self, event):
        self.Refresh()
        event.Skip()


def main():
    app= wx.App()
    frame = StartFrame()
    frame.Show()
    app.MainLoop()

if __name__ == "__main__":
    main()