如何在 tkinter 中重复获取新行的值？ 下面的代码仅获取 tkinter 条目小部件中的最后一行

Question

The code below is only displaying the last row's values in tkinter entry box, whereas when printing in the shell, it prints all the values from each row. This is how I want it to be displayed in tkinter.

data=csv.reader(file)
for r in data:
    x_var.set(r[1]) #x_var entry widget here r keeps incrementing but displays only the last row value.[1] is first column.
    y_var.set(r[2]) #y_var entry widget here r keeps incrementing but displays only the last row value.[2 is second column.
    z_var.set(r[3]) #z_var entry widget here r keeps incrementing but displays only the last row value.[3] is third column.

is only displaying the last row's values in tkinter, whereas in a shell, I want to create new tkinter entry box automatically for each row or get one row value at a time from csv in the above entry widget. In short if I can control r or increment (r+=1) it manually using loop or any condition.

Answer 1

    reader=csv.reader(file) #csv.reader is a generator that reads line by line
    for i,j,k,l in reader:
        print(i,j,k,l)
        x_var.set(j)                                                           
        print(j)
        y_var.set(k)                               
        print(k)    
        z_var.set(l)                               
        print(l)
        break  

the above code reads the first row and breaks out are you looking for something to repeat the above code after some time?

Answer 2

This is because the values are quickly changing from the first row's values to the last row's values. To see this, import time and add time.sleep(num) to the end of the for loop, where num is any number. A solution is as follows:

data = csv.reader(file)
for r in data:
    x_var.set(x_var.get() + r[1])
    y_var.set(y_var.get() + r[2])
    z_var.set(z_var.get() + r[3])

In response to your last comment, whose answer was too long to put in a comment:

Would you be able to make a function:

def func(num):
    global i
    i += 1
    x_var.set(data[num])
    y_var.set(data[num])
    z_var.set(data[num])

And for labels:

def func(num):
    global i
    i += 1
    lbl1.config(text=data[num])
    lbl2.config(text=data[num])
    lbl3.config(text=data[num])

And make a button:

import tkinter as tk
i = 0
btn = tk.Button(master, text="Show next values", command=lambda: func(i))
btn.pack()

where master is the widget master. This would do what you want to do, but to do this without the button would, in my knowledge, require much manual work, which defeats the point of python.

Answer 3

You can use a global variable to keep track of the current row, I've called mine current_row . The next_row function uses current_row to determine which data to show and then increments it. The button command is set to next_row , so every time you press it it shows the next row.

import tkinter as tk

root = tk.Tk()

data = [[600, 250, 522, 200], [400, 210, 512, 225], [940, 250, 502, 250], [920, 250, 492, 275], [800, 240, 482, 300], [850, 230, 472, 325], [900, 220, 462, 350], [920, 210, 452, 375], [880, 220, 442, 400], [850, 230, 432, 425], [840, 245, 422, 450], [800, 250, 412, 475], [700, 255, 402, 500], [600, 250, 392, 525]]
current_row = 0

def next_row():
    global current_row
    x_var.set(data[current_row][1])
    y_var.set(data[current_row][2])
    z_var.set(data[current_row][3])
    current_row += 1

x_var = tk.IntVar(root)
y_var = tk.IntVar(root)
z_var = tk.IntVar(root)
next_row() # show first row

x_ent = tk.Entry(root, textvariable = x_var, width = 10)
y_ent = tk.Entry(root, textvariable = y_var, width = 10)
z_ent = tk.Entry(root, textvariable = z_var, width = 10)
x_ent.grid(row = 0, column = 0)
y_ent.grid(row = 0, column = 1)
z_ent.grid(row = 0, column = 2)

next_btn = tk.Button(root, text = "Show next row", command = next_row)
next_btn.grid(row = 1, column = 0, columnspan = 3)

root.mainloop()