Tkinter theme is slow

Question

I'm using this them in py tkinter program. My problem is that I make like 20 buttonst, it becomes very slow. I know that this is beacuse all the buttons have images. I alredy get a suggestion, that use OpenCV instead of tkinter to load images. But the images are loaded in the Tcl not in the Python file.

Any suggestions to overcome this issue?

UPDATE:

def draw(self):
   self['width'] = self.width
   self['height'] = self.height
   self['background'] = COLORS['GRAY3']
   
   s_btn_add_scene = ttk.Style()
   s_btn_add_scene.configure('scene.TButton', font=(FONT_NAME, self.font_size), padding=(0, 0))
   
   btn_add_scene = ttk.Button(self.viewport, text='Add Scene', style='scene.TButton')
   
   cf_scenes = CollapsingFrame(self.viewport, padding=10)
   btn_remove = ttk.Button(None, text='Remove', style='scene.TButton')
   btn_add = ttk.Button(None, text='+', style='scene.TButton', width=3)
   
   btn_add_scene.pack(anchor='nw', pady=10, padx=8)
   cf_scenes.pack(expand=True, fill='x', anchor='n')        

   for i in range(20):
       #TODO: remove   
       go = randint(0, 100)
       
       frame1 = ttk.Frame(cf_scenes, padding=10)
       
       for j in range(go):
           ttk.Label(frame1, text=f"GameEntity{j}").pack(anchor='w')
           
       cf_scenes.add(frame1, title=f"NewScene{i}", collapsed=True, widgets=[btn_remove, btn_add])

Answer 1

I'm no expert in this area, but I believe the trend is to start using SVG graphics for themes rather than bitmapped images, for greater efficiency. I see that the same guy has an svg theme at https://github.com/rdbende/Sun-Valley-ttk-theme-svg . It might be worth trying that just to see if the slowness goes away.

Answer 2

Unfortunately tkinter themes are quite slow on Windows and macOS because reasons ... (on Linux there's not much problem with it, as that's the platform the toolkit was originally written for).

There's another theme I made (sv-ttk) which is a bit better in terms of performance, but if you want something modern and snappy, you should look into alternative GUI toolkits.

The theme is also installable as a Python package: pip install sv-ttk