Hi,
I am using Fedora 35 on Wayland, Python 3.9 and wxpython 4.1.1
I encountered an odd behavior where after applying a text effect on a range of text in RichTextCtrl, the text moves up a little bit.
I am having trouble finding out why that happens. Below is a minimal example. (This is taken from a bigger project where the effect is used to show spellcheck errors).
Run the script and click the “Strike” button. The word “text” will be stricken and the rest of the text including the word will move up a few pixels.
Does anyone have any idea how to prevent that from happening?
Thanks.
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)
self._stylesheet = rt.RichTextStyleSheet()
self._stylesheet.SetName('Stylesheet')
self.rtc.SetStyleSheet(self._stylesheet)
self._button = wx.Button(self, -1, 'Strike')
self.Bind(wx.EVT_BUTTON, self.strike_text, self._button)
self.sizer.Add(self.rtc, 1, flag=wx.EXPAND)
self.sizer.Add(self._button)
self.SetSizer(self.sizer)
self._create_styles()
self._insert_sample_text()
def _create_styles(self) -> None:
"""
Create styles for rich text control.
:return: None
"""
# Normal style
stl_paragraph: rt.RichTextAttr = rt.RichTextAttr()
stl_paragraph.SetFontSize(12)
stl_paragraph.SetAlignment(wx.TEXT_ALIGNMENT_LEFT)
stl_paragraph.SetFontWeight(wx.FONTWEIGHT_NORMAL)
stl_paragraph.SetParagraphSpacingBefore(0)
stl_paragraph.SetParagraphSpacingAfter(0)
stl_paragraph.SetParagraphStyleName('par')
stl_paragraph.SetFontFaceName('par')
style_paragraph: rt.RichTextParagraphStyleDefinition = rt.RichTextParagraphStyleDefinition('paragraph')
style_paragraph.SetStyle(stl_paragraph)
style_paragraph.SetNextStyle('paragraph')
self._stylesheet.AddParagraphStyle(style_paragraph)
self.rtc.ApplyStyle(style_paragraph)
self.rtc.SetDefaultStyle(stl_paragraph)
def strike_text(self, event: wx.CommandEvent) -> None:
"""
Strike a range of text.
:param event: Unused.
:return: None
"""
self.rtc.BeginSuppressUndo()
# The selection would move the caret if the position was not restored.
position = self.rtc.GetCaretPosition()
# Remove all striking from anything that was stricken previously.
self.rtc.SelectAll()
self.apply_effect(False, self.rtc.GetSelectionRange())
self.rtc.SelectNone()
word_range = rt.RichTextRange(5, 10)
self.apply_effect(True, word_range)
self.rtc.SetCaretPosition(position)
self.rtc.EndSuppressUndo()
def apply_effect(self, enable: bool, text_range: rt.RichTextRange) -> None:
"""
Apply text effect to range of characters.
:param enable: True to turn effect on.
:param text_range: Range for the effect.
:return: None
"""
# TODO red wavy spellcheck underline is not implemented yet.
effect = wx.TEXT_ATTR_EFFECT_STRIKETHROUGH
attrs: rt.RichTextAttr = rt.RichTextAttr()
attr = rt.RichTextAttr()
self.rtc.GetStyleForRange(text_range, attr)
if enable:
attrs.SetFlags(wx.TEXT_ATTR_EFFECTS)
attrs.SetTextEffects(effect)
attrs.SetTextEffectFlags(effect)
else:
attrs.SetFlags(attrs.GetFlags() & ~wx.TEXT_ATTR_EFFECTS)
attrs.SetTextEffects(attrs.GetTextEffectFlags() & ~effect)
attrs.SetTextEffectFlags(attrs.GetTextEffectFlags() & ~effect)
self.rtc.SetStyleEx(text_range, attrs, rt.RICHTEXT_SETSTYLE_OPTIMIZE | rt.RICHTEXT_SETSTYLE_CHARACTERS_ONLY)
def _insert_sample_text(self) -> None:
"""
Insert sample text.
:return: None
"""
self.rtc.ApplyStyle(self._stylesheet.FindParagraphStyle('paragraph'))
self.rtc.BeginParagraphStyle('paragraph')
self.rtc.WriteText('Test text that shows an odd behavior.')
self.rtc.Newline()
self.rtc.EndParagraphStyle()
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=(500, 300), style=wx.DEFAULT_FRAME_STYLE)
self.SetTopWindow(self.frame)
self.frame.Show()
return True
if __name__ == "__main__":
app = MyApp()
app.MainLoop()
