Tkinter button inside for loop issue in Python

Question

I'm trying to build a simple GUI where there's a list of sentences, and there's a for loop with tkinter Text where these sentences are being displayed, I want the loop to iterate and show the next sentence from the list only when the button is clicked, how can I achieve this, thanks. I tried wait_variable but it's not working.

var = IntVar()
for entry in input_texts:
    scroll = Scrollbar(canvas)
    display = Text(canvas, height=2, width=110)
    display.insert(INSERT, entry)
    display.grid(row=1, sticky='w')

    scroll.grid(row=1, column=4)
    display.config(yscrollcommand=scroll.set)
    scroll.config(command=display.yview)

    confirm = Button(canvas, text=" NEXT ", command=pause)
    confirm.grid(row=4, sticky='w')
    confirm.wait_variable(var)
    var.set(0)

canvas.resizable(width=False, height=False)
canvas.mainloop()

added code, 'confirm' is the concerned button here, and input_texts is the list of sentences. — S.Mandal
– S.Mandal, Commented Apr 26, 2018 at 17:59

Ron Norris · Accepted Answer · 2018-04-27 11:02:29Z

1

There are many ways to do this. Here is a fairly simple way to do it.

import tkinter as tk

class Sentence:

    def __init__(self, master):
        self.text = tk.Text(master)
        self.scrolly = tk.Scrollbar(master, command=self.text.yview)
        self.scrolly.grid(row=0, column=1, sticky='nsw')
        self.text.grid(row=0, column=0, sticky='news')
        self.text['yscrollcommand'] = self.scrolly.set
        # Set the command attribute of the button to call a method that
        # inserts the next line into the text widget.
        self.button = tk.Button(master, text='Next', command=self.insertLine)
        self.button.grid(row=1, pady=10, column=0, sticky='n')
        self.data = ['Here is an example', 'This should be second', '3rd', 'and so on...']
        self.data.reverse()


    def insertLine(self):
        if len(self.data):
            # Pull the first line from the list and display it
            line = self.data.pop()
            self.text.insert(tk.END, line + '\n')
            self.text.see(tk.END)
        else:
            print("No more data")


if __name__ == '__main__':
    root = tk.Tk()
    sentence = Sentence(root)
    root.mainloop()

edited Apr 27, 2018 at 11:02

answered Apr 26, 2018 at 18:32

Ron Norris

2,7001 gold badge12 silver badges13 bronze badges

Sign up to request clarification or add additional context in comments.

2 Comments

S.Mandal Over a year ago

Thanks a lot, stupid of me not to think it this way. I'm still having one minor issue though, as texts are being inserted into the textbox, the scrolling down action is not happening automatically, is it possible to do that? By the way even deleting the previous texts while the new one is being inserted will be fine as well, and probably simpler.

Ron Norris Over a year ago

If you'd rather not delete the information at the top, but scroll, I've added the line in insertLine that will do that automatically for you.

Collectives™ on Stack Overflow

Tkinter button inside for loop issue in Python

1 Answer 1

2 Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

2 Comments

Your Answer

Sign up or log in

Post as a guest

Related