Lesson 15 · 15 of 20

File and colour dialogs · tkinter

Pick files, folders and colours with tkinter's filedialog and colorchooser, and learn what each dialog returns on OK or Cancel.

tkinter · File and colour dialogs in DMarlon Studio: the example's code and the window it opens when run

filedialog opens the system's file dialogs. askopenfilename returns the chosen file's path as text, or "" when cancelled; askopenfilenames (plural) lets you pick several and returns a tuple of paths. Neither opens the file: they only tell you which one it is.

asksaveasfilename asks where to save: initialfile suggests a name, defaultextension=".txt" adds the extension if the user doesn't type one, and the system warns if the file already exists. askdirectory picks a folder. filetypes is a list of (description, pattern) pairs that filters what is shown.

colorchooser.askcolor opens the colour picker and returns the colour in two forms: (red, green, blue) and hexadecimal, "#4f8cf7"; when cancelled, (None, None). That is why run checks value[1] before painting the swatch.

Being modal, they sit behind buttons. Each row has a button and a label with the last result written with repr, so you can tell text from tuple or empty; at start they show the sample values of the shown dictionary. root.configure(padx=16, pady=12) leaves a margin around the grid.

In DMarlon Studio the Open dialog and Save dialog are in the palette: they don't show in the window, you set them up in the inspector (title, filter, extension, initial folder…) and the studio generates the code that calls askopenfilename and asksaveasfilename.

Code · main.py

import tkinter as tkfrom tkinter import ttk, filedialog, colorchooserroot = tk.Tk()root.title("File and color dialogs")root.geometry("560x240")root.configure(padx=16, pady=12)  # space around the gridTYPES = [("Text files", "*.txt"), ("All files", "*.*")]  # (description, pattern)# They return a path ("" if cancelled), a tuple of paths or a color.dialogs = {    "Open…": lambda: filedialog.askopenfilename(title="Open", filetypes=TYPES),    "Open several…": lambda: filedialog.askopenfilenames(filetypes=TYPES),    "Save as…": lambda: filedialog.asksaveasfilename(        defaultextension=".txt", initialfile="copy.txt", filetypes=TYPES),    "Folder…": lambda: filedialog.askdirectory(title="Choose a folder"),    "Color…": lambda: colorchooser.askcolor(color=swatch["bg"], title="Pick a color"),}shown = {"Open…": "/Users/ana/notes.txt", "Open several…": ("/Users/ana/a.txt", "/Users/ana/b.txt"),         "Save as…": "/Users/ana/copy.txt", "Color…": ((79, 140, 247), "#4f8cf7")}results = {name: tk.StringVar(value=repr(shown.get(name, ""))) for name in dialogs}def run(name):    value = dialogs[name]()    results[name].set(repr(value))    if name == "Color…" and value[1]:   # (None, None) when cancelled        swatch.config(bg=value[1])for row, name in enumerate(dialogs):  # a button and its result on each row    ttk.Button(root, text=name, width=14, command=lambda n=name: run(n)).grid(row=row, column=0, pady=4)    ttk.Label(root, textvariable=results[name]).grid(row=row, column=1, sticky="w", padx=10)swatch = tk.Label(root, bg="#4f8cf7", width=4)swatch.grid(row=4, column=2)root.mainloop()

Key points

askopenfilename returns a path, or "" when cancelled.
asksaveasfilename takes defaultextension and initialfile.
askcolor returns ((r, g, b), "#hex") or (None, None).
filetypes filters with (description, pattern) pairs.

Exercise

Make "Open…" read the chosen file (unless cancelled) and show in its label how many lines it has.