无法弄清楚如何阻止列和行在TkInter GUI中移位

Question

So, I am working on a final project for my Python class and am creating a GUI for a game using TkInter. I have a little 'sprite' if you will that moves across the GUI using button presses. I am trying to figure out how to stop the annoying re-sizing of the rows and columns as the 'sprite' moves around. I would also like to know how to detect if a cell is occupied or not. It would really be great if I could somehow see the grid lines of the grid, but I dont think that is possible so the next best thing would be knowing how to permanently set up the grids columns and rows and make them unchangeable. I'm sorry if I'm not being clear on what I want I just have dozens of ideas running around in my head.

here is my code so far

from tkinter import *
from tkinter.constants import *

master= Tk()
master.resizable(width=False, height=False)

#for erasing displayed text when not needed anymore
wordsShowing = 0


#for testing button function with map movement
#url for image is http://files.softicons.com/download/game-icons/minecraft-avatars-icons-by-stefan-kroeber/png/50x50/slime.png if you want to see exactly what im seeing
pic = PhotoImage(file="C:\\Users\\Bill\\Desktop\\Python\\Final\\slime.png")
image = Label(master, image=pic)
image.grid(row=0, column=3, columnspan=1, rowspan=1, padx=0, pady=0)


#button functions (im not sure which buttons we will actually be using but im trying to cover all our bases)
def left():
    while wordsShowing == 1:
        varLabel.grid_remove()
        wordsShowing = 0
    info = image.grid_info()
    move = info["column"]
    stay = info["row"]
    if move > 0:
        image.grid_remove()
        image.grid(row=stay, column=move-1, columnspan=1, rowspan=1, padx=0, pady=0)
    else:
        varLabel = Label(master, text='Sorry, you can not go that direction.')
        varLabel.grid(row=1, column=2, rowspan=4)
        wordsShowing = 1
    global wordsShowing
    global varLabel

def right():
    while wordsShowing == 1:
        varLabel.grid_remove()
        wordsShowing = 0
    info = image.grid_info()
    move = info["column"]
    stay = info["row"]
    if move < 4:
        image.grid_remove()
        image.grid(row=stay, column=move+1, columnspan=1, rowspan=1, padx=0, pady=0)
    else:
        varLabel = Label(master, text='Sorry, you can not go that direction.')
        varLabel.grid(row=1, column=2, rowspan=4)
        wordsShowing = 1
    global wordsShowing
    global varLabel


def down():
    while wordsShowing == 1:
        varLabel.grid_remove()
        wordsShowing = 0
    info = image.grid_info()
    move = info["row"]
    stay = info["column"]
    if move < 5:
        image.grid_remove()
        image.grid(row=move+1, column=stay, columnspan=1, rowspan=1, padx=0, pady=0)
    else:
        varLabel = Label(master, text='Sorry, you can not go that direction.')
        varLabel.grid(row=1, column=2, rowspan=4)
        wordsShowing = 1
    global wordsShowing
    global varLabel


def up():
    while wordsShowing == 1:
        varLabel.grid_remove()
    wordsShowing = 0
    info = image.grid_info()
    move = info["row"]
    stay = info["column"]
    if move > 0:
        image.grid_remove()
        image.grid(row=move-1, column=stay, columnspan=1, rowspan=1, padx=0, pady=0)
    else:
        varLabel = Label(master, text='Sorry, you can not go that direction.')
        varLabel.grid(row=1, column=2, rowspan=4)
        wordsShowing = 1
    global wordsShowing
    global varLabel


def submit():
    var = command.get()
    varLabel = Label(master, text=var)
    varLabel.grid(row=1, column=2, rowspan=4)
    wordsShowing = 1
    global wordsShowing
    global varLabel


#created widgets
label1 = Label(master, text="Enter a command:")
command = Entry(master, width=80)
leftButton = Button(master, text="<", command=left)
rightButton = Button(master, text=">", command=right)
downButton = Button(master, text="v", command=down)
upButton = Button(master, text="^", command=up)
submitButton = Button(master, text="SUBMIT", command=submit)

#display widgets
label1.grid(row=5, column=1, sticky=E)
command.grid(row=5, column=2)
leftButton.grid(row=2, column=2, sticky=E, padx=3)
rightButton.grid(row=2, column=3)
downButton.grid(row=3, column=3, sticky=W)
upButton.grid(row=1, column=3, sticky=W)
submitButton.grid(row=5, column=3, pady=5, padx=5)

Any help you can give would be greatly appreciated. Thank you.

Answer 1

A minimum size for each grid cell can be set with the function .minsize. If you set a minimum size that's always larger than the widgets you put into each cell, the cells will not change size as you move things around. See this manual page: http://infohost.nmt.edu/tcc/help/pubs/tkinter/web/grid-config.html .

Answer 2

Well there are a few issues with your code if you are working on Python 3.X.

• The first problem is that you are trying to use a .png file whereas the PhotoImage class only accepts .gif , .pgm , or .ppm files. You can read the doc at PhotoImage Doc .
• The next issue, a warning, is that you are setting variables as global at the end of your functions. The way python works is that if a variable is declared inside a function it is local, so what you normally do is tell it at the start of the function, ok this variable is global, and THEN proceed to modifying it. If not you can't be sure that the variable you are working on is the global one you want.

• For the grid resizing, your best option is to put the buttons inside a grid, inside the grid so that their size is independent of the size of cells in the main grid. And it is better to display things on a frame rather than directly on master. I would change your code to be something like (and replace Label s and Frame s from functions to construct on master to construct on gridFrame ):

   WIDTH = 200 HEIGHT = 200 master= Tk() master.resizable(width=False, height=False) gridFrame = Frame(master, width=WIDTH, height=HEIGHT) gridFrame.grid() # Your function code goes here buttonGrid = Frame(gridFrame) buttonGrid.grid(row=4, column=3, sticky=N) # created widgets label1 = Label(gridFrame, text="Enter a command:") command = Entry(gridFrame, width=80) leftButton = Button(buttonGrid, text="<", command=left) rightButton = Button(buttonGrid, text=">", command=right) downButton = Button(buttonGrid, text="v", command=down) upButton = Button(buttonGrid, text="^", command=up) submitButton = Button(gridFrame, text="SUBMIT", command=submit) # display widgets label1.grid(row=5, column=1, sticky=E) command.grid(row=5, column=2) leftButton.grid(row=1, column=0, sticky=E) rightButton.grid(row=1, column=2, sticky=W) downButton.grid(row=2, column=1, sticky=N) upButton.grid(row=0, column=1, sticky=S) submitButton.grid(row=5, column=3, pady=5, padx=5) 

• The bit about knowing where something is can be easily maintainted by simply having a matrix that is initially empty and when you place something at a certain row and column, change those indices of the matrix to True and then simply check the matrix at position [i][j] to see if it is occupied

Hope that helped.