How to change values from a matrix GUI tkinter?-CodePudding

I want to change a number from a matrix and then display it in the same tk window, but I find it hard to work with variables from an input. The r[][] should be the matrix formed with the user's input. And after all I have to display the matrix with the modification: r[0][1] = 5, in the same tk window.

from tkinter import *
import numpy as np

root = Tk()

def process():
    values = [e1.get(),e2.get(),e3.get(),e4.get()]

    a = np.zeros((2,2),dtype=np.int64)

    for i in range(2):
        for j in range(2):
                a[i][j] = values[i*2 j]
    print(a)

e1 = Entry(root)
e2 = Entry(root)
e3 = Entry(root)
e4 = Entry(root)

e1.grid(row=0,column=0,padx=10,pady=10)
e2.grid(row=0,column=1)
e3.grid(row=1,column=0,padx=10,pady=10)
e4.grid(row=1,column=1)

b = Button(root,text='Process',command=process)
b.grid(row=2,column=0,columnspan=4,sticky=E W)

root.mainloop()

r=[[e1.get(),e2.get()],[e3.get(),e4.get()]]
r[0][1]  = 5

CodePudding user response：

Tkinter GUI programs are event-driven which requires using a different programming paradigm than the one you're probably familiar with which is call Imperative programming. In other words, just about everything that happens is done in response to something the user has done, like typing on the keyboard, clicking on a graphical button, moving the mouse, etc.

I think the code below will give you a good idea of how to do what you want in a framework like that. It creates a StringVar for each Entry widget, which has the advantage what's displayed in each Entry will automatically be updated whenever the corresponding StringVar is changed (make that more-or-less automatic).

import tkinter as tk
from tkinter.constants import *

ROWS, COLS = 2, 2

def process(variables, col, row):
    try:
        value = float(variables[row][col].get())
    except ValueError:  # Nothing was entered.
        value = 0
    value  = 5
    variables[row][col].set(value)

root = tk.Tk()

# Create tkinter Variables to hold matrix element values.
matrix_elems = [[tk.StringVar(master=root)
                    for i in range(COLS)]
                        for j in range(ROWS)]

# Use Variables to create Entry widgets.
entries = [[tk.Entry(root, textvariable=matrix_elems[j][i])
                for i in range(COLS)]
                    for j in range(ROWS)]

# Position the matrix Entry widgets in a grid.
for j, row in enumerate(entries):
    for i, entry in enumerate(row):
        entry.grid(column=i, row=j)

btn = tk.Button(root, text='Process', command=lambda: process(matrix_elems, 0, 1))
btn.grid(row=2, column=0, columnspan=COLS, sticky=E W)

root.mainloop()

CodePudding user response：

Would this be what you're looking for? I deleted a bunch of code that seems to do nothing in context -- you just want to replace the text in the corner box right?

from tkinter import *

def process():
    replace(e4)

def replace(entry_loc):
    temp = int(entry_loc.get())
    temp  = 5
    entry_loc.delete(0,500)
    entry_loc.insert(0, temp)
    
root = Tk()

var_e1 = StringVar
var_e2 = StringVar
var_e3 = StringVar
var_e4 = StringVar
e1 = Entry(root, textvariable=var_e1)
e2 = Entry(root, textvariable=var_e2)
e3 = Entry(root, textvariable=var_e3)
e4 = Entry(root, textvariable=var_e4)

e1.grid(row=0, column=0, padx=10, pady=10)
e2.grid(row=0, column=1)
e3.grid(row=1, column=0, padx=10, pady=10)
e4.grid(row=1, column=1)

b = Button(root, text='Process', command=process)
b.grid(row=2, column=0, columnspan=4, sticky=E   W)

root.mainloop()