Set multiline text from a file online to a text element in pysimplegui

Question

So I have this program that grabs a text file from the internet, reads it and then set the decoded text to an element.

import PySimpleGUI as sg
import urllib.request

data = urllib.request.urlopen("link to a text file")

layout = [[sg.Text('', k='textElement')]]

window = sg.window('Foo', layout)

def setText(Text):
    for line in Text:
        decodedText = line.decode("utf-8")
        window['textElement'].update(value=decodedText)

setText(data)

while True:
    event, values = window.read()

    if event == sg.WIN_CLOSED:
        break

window.close()

Something like that. But instead it only displays the last line of the text file.

You call `window['textElement'].update(value=decodedText)` for each line in the file, so it makes sense that only the last value is there once it's done? You could just concatenate all the lines and update with that? — Grismar, Mar 25 '22 at 05:38
Oh, I didn't realize that. Could you please show how to do it? I'm a beginner in python so I don't know a lot of the things in it. — CodeSearcher, Mar 25 '22 at 05:43

score 1 · Accepted Answer · answered Mar 25 '22 at 05:52

You're decoding every line then calling .update() on the text element for each line. Instead:

def setText(Text):
    decodedText = Text.read().decode("utf-8")
    window['textElement'].update(value=decodedText)

You can just read the entire text, decode it and assign that (note that you shouldn't really name functions or variables using capitals, set_text and decided_text would be better, and Text should definitely be text or something else lowercase)

Or if you have other reasons to do it line by line:

def setText(Text):
    Text = ''.join(line for line in Text)
    decodedText = Text.decode("utf-8")
    window['textElement'].update(value=decodedText)

Note however, that your code seems to assume it's getting bytes (which would need to be encoded), while it seems to make sense you'd be getting text (i.e. str), so if you still have issues, you may simple have to skip decoding the already decoded text.

score 1 · Answer 2 · answered Mar 25 '22 at 07:07

Method update of Text element will replace full content by new values, so only last update will be shown in following code.

    for line in Text:
        decodedText = line.decode("utf-8")
        window['textElement'].update(value=decodedText)

The content of a txt file maybe large to fit in a fixed-size Text element, then a scrollbar required to view all, so it will be better to use a Multiline element here.

import urllib
import PySimpleGUI as sg

url = 'https://www.python.org/humans.txt'
try:
    response = urllib.request.urlopen(url)
    if response.code == 200:
        text = response.read().decode('utf-8')
    else:
        text = 'Failed to load following file.\n'+url
except urllib.error.HTTPError:
    text = 'Failed to load following file.\n'+url

font = ('Courier New', 11)
sg.theme('DarkBlue4')
sg.set_options(font=font)

layout = [
    [sg.Multiline(text, size=(80, 10), key='Multiline')],
    [sg.Push(), sg.Button('Exit')],
]
window = sg.Window('Window Title', layout, finalize=True)

while True:
    event, values = window.read()
    if event in (sg.WIN_CLOSED, 'Exit'):
        break

window.close()

score 0 · Answer 3 · answered Mar 26 '22 at 15:34

Jason has the right idea of using a Multiline element. Expanding on that a bit... you can "print" to a Multiline element if you want to display multiple files for example.

This way you could call the set_text multiple times and the result will be that the information is "printed" to the Multiline element each time.

import urllib
import PySimpleGUI as sg

url = 'https://www.python.org/humans.txt'

def set_text(mline:sg.Multiline, url):
    try:
        response = urllib.request.urlopen(url)
        if response.code == 200:
            text = response.read().decode('utf-8')
            mline.print(text)
        else:
            mline.print('Failed to load following file.\n'+url)
    except urllib.error.HTTPError:
        mline.print('Failed to load following file.\n'+url)

font = ('Courier New', 11)
sg.theme('DarkBlue4')
sg.set_options(font=font)

layout = [  [sg.Multiline(size=(80, 10), key='Multiline', expand_x=True, expand_y=True)],
            [sg.Push(), sg.Button('Get Example'), sg.Button('Exit')]]

window = sg.Window('Window Title', layout, resizable=True, finalize=True)

set_text(window['Multiline'], url)

while True:
    event, values = window.read()
    if event in (sg.WIN_CLOSED, 'Exit'):
        break
    elif event == 'Get Example':
        set_text(window['Multiline'], 'http://www.example.com')

window.close()

Set multiline text from a file online to a text element in pysimplegui

3 Answers3