Python Tkinter 循环使用每个新列表值更新的 3 个标签

Question

I am creating a list that takes each line from a Tkinter textarea. I want to append each line in the list to three labels,with each index in the list moving to the next label, updating the value that is next in the list when it loops back to label one.

Right now I have this but don't know how to loop back to update the labels:

    def iterate_linesRest(self):
        for line in self.textarea.get('1.0', 'end-1c').splitlines():
            # Iterate lines
            if line:
                MainFrame.pipelinelist4.append(line)
            labels=[]
            for x in MainFrame.pipelinelist4[]:
                label = Label(self,text =x)
                labels.append(label)

To put it in perspective I want something like this to occur:

pipelinelist = ["Hello", "Hi", "Apple", "John", "Mike", "Joe"]

Label 1 = Hello         Label2 = Null,    Label 3 = Null

Label 1 = Hi           Label2 = Hello    Label 3 = Null

Label 1 = Apple        Label 2 = Hi      Label 3 = Hello

Label 1 = Mike          Label2 = Apple     Label 3 = Hi
......

until it reaches the end of the list

Label 1 = Null           Label 2 = Null    Label 3 = Joe

And then Label 3 would be Null or Empty

Doing some research, I feel that making a queue of the list would be a much better approach then creating a complicated loop structure

Answer 1

I have been using your idea of the queue:

import tkinter as tk
from collections import deque

def main():
    app = App()
    app.mainloop()


class App(tk.Tk):
    def __init__(self):
        super().__init__()
        self.geometry("400x400")
        tk.Button(self, text="Labels", command=self.labels).grid(column=0, row=0)

    def labels(self):
        label_names = ['I', 'am', 'a', 'list', 'of', 'placeholders']
        label_names.extend(['Null', 'Null'])
        q = deque(['Null', 'Null', 'Null'])
        for i, val in enumerate(label_names):
            q.pop()
            q.appendleft(val)
            for j, label in enumerate(q):
                tk.Label(self, text=str(label)).grid(column=j, row=i+1)


if __name__ == '__main__':
    main()