Hi,
I am using Python 3.7.9 and wxPython 4.1.1. on Fedora 32.
I am seeing a weird behavior of a list style in RichTextCtrl
Use the code below to try it out.
Move the caret to the end of the second line and press the Return key a few times.
You will see that the indentation of the list items changes on every second line and then goes to normal on the next line. I would expect it to remain the same on all lines.
Why is this happening? Is there something wrong with the style definition?
Thanks very much and have a nice New year. 
import wx
import wx.richtext as rt
class RichTextFrame(wx.Frame):
def __init__(self, *args, **kw):
wx.Frame.__init__(self, *args, **kw)
self.rtc = rt.RichTextCtrl(self, style=wx.VSCROLL | wx.HSCROLL | wx.NO_BORDER)
self.sizer = wx.BoxSizer(wx.VERTICAL)
# Create style stylesheet and control
self._stylesheet = rt.RichTextStyleSheet()
self._stylesheet.SetName('Stylesheet')
self.rtc.SetStyleSheet(self._stylesheet)
self.sizer.Add(self.rtc, 1, flag=wx.EXPAND)
self.SetSizer(self.sizer)
self._create_styles()
self._insert_sample_text()
def _create_styles(self) -> None:
"""
Create styles for rich text control.
:return: None
"""
# List style
stl_list: rt.RichTextAttr = rt.RichTextAttr()
stl_list.SetFontSize(12)
stl_list.SetAlignment(wx.TEXT_ALIGNMENT_LEFT)
stl_list.SetFontWeight(wx.FONTWEIGHT_NORMAL)
stl_list.SetParagraphSpacingBefore(20)
stl_list.SetParagraphSpacingAfter(20)
stl_list.SetBackgroundColour(wx.GREEN)
stl_list_1: rt.RichTextAttr = rt.RichTextAttr()
stl_list_1.SetFontSize(12)
stl_list_1.SetAlignment(wx.TEXT_ALIGNMENT_LEFT)
stl_list_1.SetFontWeight(wx.FONTWEIGHT_NORMAL)
stl_list_1.SetBulletStyle(wx.TEXT_ATTR_BULLET_STYLE_STANDARD)
stl_list_1.SetLeftIndent(20, 40)
style_list: rt.RichTextListStyleDefinition = rt.RichTextListStyleDefinition('list')
style_list.SetLevelAttributes(0, stl_list_1)
style_list.SetStyle(stl_list)
style_list.SetNextStyle('list')
self._stylesheet.AddListStyle(style_list)
self.rtc.SetStyleSheet(self._stylesheet)
def _insert_sample_text(self) -> None:
"""
Insert sample text.
:return: None
"""
self.rtc.BeginListStyle('list', 0)
self.rtc.WriteText('Example list item 1')
self.rtc.Newline()
self.rtc.WriteText('Example list item 2')
self.rtc.Newline()
self.rtc.WriteText('Example list item 3')
self.rtc.Newline()
self.rtc.EndListStyle()
class MyApp(wx.App):
"""
Main class for running the gui
"""
def __init__(self):
wx.App.__init__(self)
self.frame = None
def OnInit(self):
self.frame = RichTextFrame(None, -1, "RichTextCtrl", size=(900, 700), style=wx.DEFAULT_FRAME_STYLE)
self.SetTopWindow(self.frame)
self.frame.Show()
return True
if __name__ == "__main__":
app = MyApp()
app.MainLoop()