Python Tkinter Button Widget Won't Move

Question

I've been working on a tic-tac-toe projejct, and I am planning on creating 9 button widgets with a picture on each one of them. I want to move them so they'll be 3 on a line and 3 in a row. Here's my code:

#imports:
from Tkinter import *
from PIL import ImageTk, Image

#~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
#~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
#constants
#~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
#classes:
class App(Frame):
    def __init__(self, master=None):
        Frame.__init__(self, master)
        self.pack()
#~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
myapp = App()

class GUI:
    def __init__(self):
        self.myapp = myapp
        self.myapp.master.title("tkname")
        self.myapp.master.maxsize(2000, 1200)

    def create_and_pack_canvas(self, game_board_height, game_board_width):
        canvas = Canvas(height = game_board_height, width = game_board_width)
        canvas.pack(expand=1, fill=BOTH)
        return canvas

    def form_game_board(self):
        x = 404
        y = 150
        canvas = self.create_and_pack_canvas(1000, 1000)

        for i in range(3):
            for j in range(3):
                btn = gameButton("")
                btn.create_and_pack(canvas, x, y)
                x += 200
            x = 404
            y += 208

        self.myapp.mainloop()
#~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
class gameButton:
    def __init__(self, picture_param):
        self.picture = ImageTk.PhotoImage(Image.open("somepic"))
        self.picture_height = self.picture.height()
        self.picture_width = self.picture.width()

    def callback(self):
        print 10

    def create_and_pack(self, canvas, x_pixels, y_pixels):
        self.b = Button(myapp, text="Print 10~", command = self.callback, image = self.picture)
        self.b.pack()
        #self.b.place(bordermode = OUTSIDE, x = x_pixels, y = y_pixels)

    def __str__(self):
        pass
#~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
#~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
#main
def main():
    gui = GUI()
    gui.form_game_board()

if __name__ == "__main__":
    main()

Please note that there's this line:

#self.b.place(bordermode = OUTSIDE, x = x_pixels, y = y_pixels)

In the code, which I've put as a note, which is basically the line that's supposed to move the buttons. If you run the code, it'll simply put all the buttons one under another in a row, 9 of them. After the self.b.place() line, they all simply disappear. Maybe they moved somewhere too far, maybe not, but I assume the place() isn't working, and I've had trouble figuring why.

Thanks in advance.

Answer 1

Your best bet would likely be to use the grid geometry manager, see: http://www.effbot.org/tkinterbook/grid.htm

Instead of creating a GameButton class, I would put something like this in my GUI class:

    button_list = []
    list_index_counter = 0
    row_counter = 0
    column_counter = 0
    for num in range(9):
        self.button = tk.Button(canvas,
                                text="Print 10~",
                                command=self.callback,
                                image=self.callback)
        button_list.append(self.button)
        button_list[list_index_counter].grid(row=row_counter, column=column_counter)
        list_index_counter += 1
        if column_counter < (2): # it will hit this twice
            column_counter += 1
        else:                    # then this once, then back to the other one
            row_counter += 1
            column_counter = 0

This will neatly grid your buttons into a 3x3 grid.

The button_list allows you to keep a reference to the button objects, making them easier to access later on, you can use button_list[some_index].grid_info()["row"/"column"] to obtain the row or column that a button is gridded in, for example.

This is the standard way to create a set of similar widgets, and evades the problem of generating and maintaining names with lots of identical repeated code, without needing to create a new class for it.

A word of warning, from effbot:

Warning: Never mix grid and pack in the same master window. Tkinter will happily spend the rest of your lifetime trying to negotiate a solution that both managers are happy with. Instead of waiting, kill the application, and take another look at your code. A common mistake is to use the wrong parent for some of the widgets.

Finally, as @Terry Jan Reedy said, you don't need a Canvas for this, likely a Frame, or just a straightforward Tk() would be much better.