ttk creating and using a custom theme

Solution 1:

I was making this far too difficult.

Here was the solution for anybody else trying to figure this out:

from tkinter import *
from tkinter import ttk

class Main:
    def __init__(self, master):
        self.master = master
        self.main_button = ttk.Button(self.master, text = 'New', command = self.new_window)
        self.main_button.grid()

    def new_window(self):
        pop_up = Top(self.master)

class Top:
    def __init__(self, master):
        pop_up = self.pop_up = Toplevel(master)
        self.pop_up_frame = ttk.Frame(pop_up, height = 100, width = 100)
        self.pop_up_frame.grid(sticky = E+W+S+N)
        self.s = ttk.Style()
        self.s.theme_create('shadow', parent = 'default')

        print(self.s.theme_names())

        self.c1_button = ttk.Button(pop_up, text = 'Default', command = self.get_default)
        self.c2_button = ttk.Button(pop_up, text = 'Vista', command = self.get_shadow)

        self.c1_button.grid()
        self.c2_button.grid()

    def get_default(self):
        self.s.theme_use('default')

    def get_shadow(self):
        self.s.theme_use('vista')
        self.s.configure('TButton', foreground = 'white', background = 'blue')
        self.s.configure('TFrame', background = 'black')



root = Tk()

app = Main(root)

root.mainloop()

Solution 2:

To simplify Gregory6106's answer, you can modify your current theme theme using .configure().

from tkinter import *
from tkinter import ttk

class MainPage(ttk.Frame):
    def __init__(self, master):
        ttk.Frame.__init__(self, master)
        self.main_label = ttk.Label(self, text="Pointless Text")
        self.main_button = ttk.Button(self, text="Pointless Button")
        self.main_label.pack(padx=5, pady=5)
        self.main_button.pack(padx=5, pady=5)

        # Configure custom theme
        self.s = ttk.Style()
        self.s.configure('TLabel', foreground='red', background='grey')
        self.s.configure('TButton', foreground='white', background='blue')
        self.s.configure('TFrame', background='black')


root = Tk()
app_frame = MainPage(root)
app_frame.pack()
root.mainloop()

Note: This solution works by configuring the pre-existing theme rather than creating a new one. As a result, this may not work if you plan on swapping back to the original theme during runtime.