We Keep Coding

Retrieve the input value of an entry - Tkinter

I am just getting started with making basic GUI's with Tkinter.
I have previously created a script in python and I wanted to create a basic GUI for it.
My issue is I need to get the value of an entry widget to use as a parameter value, but methods online are not working for me.
This is what I am trying.
def retrieve_input():
eq_input = eq_textbox.get()
return eq_input
equation_input = retrieve_input()
eq_textbox is my entry and equation_input will be the parameter value.

from tkinter import *
window = Tk()
entry_var = StringVar() #initializing a string var
eq_textbox = Entry(window, textvariable = entry_var) #add textvariabe to store value
def retrieve_input():
eq_input = entry_var.get() #see here
return eq_input
equation_input = retrieve_input()
window.mainloop()
You need a varible to store that value... see above

Python3 Print Tuple in another class [duplicate]

I am trying to set the text of an Entry widget using a button in a GUI using the tkinter module.
This GUI is to help me classify thousands of words into five categories. Each of the categories has a button. I was hoping that using a button would significantly speed me up and I want to double check the words every time otherwise I would just use the button and have the GUI process the current word and bring the next word.
The command buttons for some reason are not behaving like I want them to. This is an example:
import tkinter as tk
from tkinter import ttk
win = tk.Tk()
v = tk.StringVar()
def setText(word):
v.set(word)
a = ttk.Button(win, text="plant", command=setText("plant"))
a.pack()
b = ttk.Button(win, text="animal", command=setText("animal"))
b.pack()
c = ttk.Entry(win, textvariable=v)
c.pack()
win.mainloop()
So far, when I am able to compile, the click does nothing.

You might want to use insert method. You can find the documentation for the Tkinter Entry Widget here.
This script inserts a text into Entry. The inserted text can be changed in command parameter of the Button.
from tkinter import *
def set_text(text):
e.delete(0,END)
e.insert(0,text)
return
win = Tk()
e = Entry(win,width=10)
e.pack()
b1 = Button(win,text="animal",command=lambda:set_text("animal"))
b1.pack()
b2 = Button(win,text="plant",command=lambda:set_text("plant"))
b2.pack()
win.mainloop()

If you use a "text variable" tk.StringVar(), you can just set() that.
No need to use the Entry delete and insert. Moreover, those functions don't work when the Entry is disabled or readonly! The text variable method, however, does work under those conditions as well.
import Tkinter as tk
...
entry_text = tk.StringVar()
entry = tk.Entry( master, textvariable=entry_text )
entry_text.set( "Hello World" )

You can choose between the following two methods to set the text of an Entry widget. For the examples, assume imported library import tkinter as tk and root window root = tk.Tk().
Method A: Use delete and insert
Widget Entry provides methods delete and insert which can be used to set its text to a new value. First, you'll have to remove any former, old text from Entry with delete which needs the positions where to start and end the deletion. Since we want to remove the full old text, we start at 0 and end at wherever the end currently is. We can access that value via END. Afterwards the Entry is empty and we can insert new_text at position 0.
entry = tk.Entry(root)
new_text = "Example text"
entry.delete(0, tk.END)
entry.insert(0, new_text)
Method B: Use StringVar
You have to create a new StringVar object called entry_text in the example. Also, your Entry widget has to be created with keyword argument textvariable. Afterwards, every time you change entry_text with set, the text will automatically show up in the Entry widget.
entry_text = tk.StringVar()
entry = tk.Entry(root, textvariable=entry_text)
new_text = "Example text"
entry_text.set(new_text)
Complete working example which contains both methods to set the text via Button:
This window
is generated by the following complete working example:
import tkinter as tk
def button_1_click():
# define new text (you can modify this to your needs!)
new_text = "Button 1 clicked!"
# delete content from position 0 to end
entry.delete(0, tk.END)
# insert new_text at position 0
entry.insert(0, new_text)
def button_2_click():
# define new text (you can modify this to your needs!)
new_text = "Button 2 clicked!"
# set connected text variable to new_text
entry_text.set(new_text)
root = tk.Tk()
entry_text = tk.StringVar()
entry = tk.Entry(root, textvariable=entry_text)
button_1 = tk.Button(root, text="Button 1", command=button_1_click)
button_2 = tk.Button(root, text="Button 2", command=button_2_click)
entry.pack(side=tk.TOP)
button_1.pack(side=tk.LEFT)
button_2.pack(side=tk.LEFT)
root.mainloop()

Your problem is that when you do this:
a = Button(win, text="plant", command=setText("plant"))
it tries to evaluate what to set for the command. So when instantiating the Button object, it actually calls setText("plant"). This is wrong, because you don't want to call the setText method yet. Then it takes the return value of this call (which is None), and sets that to the command of the button. That's why clicking the button does nothing, because there is no command set for it.
If you do as Milan Skála suggested and use a lambda expression instead, then your code will work (assuming you fix the indentation and the parentheses).
Instead of command=setText("plant"), which actually calls the function, you can set command=lambda:setText("plant") which specifies something which will call the function later, when you want to call it.
If you don't like lambdas, another (slightly more cumbersome) way would be to define a pair of functions to do what you want:
def set_to_plant():
set_text("plant")
def set_to_animal():
set_text("animal")
and then you can use command=set_to_plant and command=set_to_animal - these will evaluate to the corresponding functions, but are definitely not the same as command=set_to_plant() which would of course evaluate to None again.

One way would be to inherit a new class,EntryWithSet, and defining set method that makes use of delete and insert methods of the Entry class objects:
try: # In order to be able to import tkinter for
import tkinter as tk # either in python 2 or in python 3
except ImportError:
import Tkinter as tk
class EntryWithSet(tk.Entry):
"""
A subclass to Entry that has a set method for setting its text to
a given string, much like a Variable class.
"""
def __init__(self, master, *args, **kwargs):
tk.Entry.__init__(self, master, *args, **kwargs)
def set(self, text_string):
"""
Sets the object's text to text_string.
"""
self.delete('0', 'end')
self.insert('0', text_string)
def on_button_click():
import random, string
rand_str = ''.join(random.choice(string.ascii_letters) for _ in range(19))
entry.set(rand_str)
if __name__ == '__main__':
root = tk.Tk()
entry = EntryWithSet(root)
entry.pack()
tk.Button(root, text="Set", command=on_button_click).pack()
tk.mainloop()

e= StringVar()
def fileDialog():
filename = filedialog.askopenfilename(initialdir = "/",title = "Select A
File",filetype = (("jpeg","*.jpg"),("png","*.png"),("All Files","*.*")))
e.set(filename)
la = Entry(self,textvariable = e,width = 30).place(x=230,y=330)
butt=Button(self,text="Browse",width=7,command=fileDialog).place(x=430,y=328)

Tkinter: AttributeError using .get()

I am trying to retrieve a variable from a Tkinter Wiget but I am running into this error message:
AttributeError: 'int' object has no attribute 'get'
Here is the widget code
JobNEntry = tkinter.Entry(menu, textvariable = tk.IntVar(JobNo))
JobNEntry.grid(row=2, column=2, sticky="W")
Here is the call code
JobNo=JobNo.get()
Also I need to know if the variable JobNo is writable to a file.
Thanks in advance

The get() method is part of several widgets in tkinter and is not something that you can use on a normal int or str object. get() must be called on a variable that is a widget object that has a get() method, like Entry.
Its likely you need to do:
JobNEntry.get()
This will get the current value from the entry field as a string.
If you want to save the value of that string you can. There are several tutorials on Stack Overflow and the web that go into detail on how to save a string to a file.
Looking at the code you have shown us, it's possible you have not created your IntVar() correctly.
Make sure you define the IntVar() first then set that variable as the textvariable.
Something like this:
JobNo = tk.IntVar()
JobNEntry = tkinter.Entry(menu, textvariable = JobNo)

The attribute error might be because you havnt already initialized the variable JobNo as an 'IntVar'
This is the code i have come up with :
import tkinter as tkinter
menu=tkinter.Tk()
JobNo=tkinter.IntVar()
JobNEntry = tkinter.Entry(menu, textvariable = JobNo)
JobNEntry.grid(row=2, column=2, sticky="W")
JobNo=JobNo.get()
menu.mainloop()
You need to initialize JobNo as an Integer Variable using IntVar()
JobNo=tkinter.IntVar()
And then use it in the Entrybox.
If you had some string to add to the entry, you should initialise as StringVar()
Also when you initialize, make sure you do it after opening the Tk window.(here i put it after menu=tkinter.Tk())

Something like this:
from tkinter import *
from tkinter import ttk
def save_job_no():
try:
n = job_no.get()
except TclError:
status.config(text = "This is not an integer")
return False
status.config(text="")
f = open("my_file.txt", "w")
f.write(str(n))
return True
root = Tk()
job_no = IntVar()
entry = ttk.Entry(root, width = 30, textvariable = job_no)
entry.grid()
label = ttk.Label(root, textvariable = job_no)
label.grid()
status = ttk.Label(root)
status.grid()
button = ttk.Button(root, text = "Write to a file", command = save_job_no)
button.grid()
root.mainloop()

Label variables for exchange rate calculator [duplicate]

I am having trouble with using a key binding to change the value of a label or any parameter.
This is my code:
from tkinter import*
class MyGUI:
def __init__(self):
self.__mainWindow = Tk()
#self.fram1 = Frame(self.__mainWindow)
self.labelText = 'Enter amount to deposit'
self.depositLabel = Label(self.__mainWindow, text = self.labelText)
self.depositEntry = Entry(self.__mainWindow, width = 10)
self.depositEntry.bind('<Return>', self.depositCallBack)
self.depositLabel.pack()
self.depositEntry.pack()
mainloop()
def depositCallBack(self,event):
self.labelText = 'change the value'
print(self.labelText)
myGUI = MyGUI()
When I run this, I click the entrybox and hit enter, hoping that the label will change value to 'change the value'. However, while it does print that text, the label remains unchanged.
From looking at other questions on similar problems and issues, I have figured how to work with some of this outside a class, but I'm having some difficulties with doing it inside a class.

self.labelText = 'change the value'
The above sentence makes labelText change the value, but not change depositLabel's text.
To change depositLabel's text, use one of following setences:
self.depositLabel['text'] = 'change the value'
OR
self.depositLabel.config(text='change the value')

You can also define a textvariable when creating the Label, and change the textvariable to update the text in the label.
Here's an example:
labelText = StringVar()
depositLabel = Label(self, textvariable=labelText)
depositLabel.grid()
def updateDepositLabel(txt) # you may have to use *args in some cases
labelText.set(txt)
There's no need to update the text in depositLabel manually. Tk does that for you.

Use the config method to change the value of the label:
top = Tk()
l = Label(top)
l.pack()
l.config(text = "Hello World", width = "50")

Here is another one, I think. Just for reference.
Let's set a variable to be an instantance of class StringVar
If you program Tk using the Tcl language, you can ask the system to let you know when a variable is changed. The Tk toolkit can use this feature, called tracing, to update certain widgets when an associated variable is modified.
There’s no way to track changes to Python variables, but Tkinter
allows you to create variable wrappers that can be used wherever Tk
can use a traced Tcl variable.
text = StringVar()
self.depositLabel = Label(self.__mainWindow, text = self.labelText, textvariable = text)
# ^^^^^^^^^^^^^^^^^^^
def depositCallBack(self,event):
text.set('change the value')

I made a small tkinter application which is sets the label after button clicked
#!/usr/bin/env python
from Tkinter import *
from tkFileDialog import askopenfilename
from tkFileDialog import askdirectory
class Application:
def __init__(self, master):
frame = Frame(master,width=200,height=200)
frame.pack()
self.log_file_btn = Button(frame, text="Select Log File", command=self.selectLogFile,width=25).grid(row=0)
self.image_folder_btn = Button(frame, text="Select Image Folder", command=self.selectImageFile,width=25).grid(row=1)
self.quite_button = Button(frame, text="QUIT", fg="red", command=frame.quit,width=25).grid(row=5)
self.logFilePath =StringVar()
self.imageFilePath = StringVar()
self.labelFolder = Label(frame,textvariable=self.logFilePath).grid(row=0,column=1)
self.labelImageFile = Label(frame,textvariable = self.imageFilePath).grid(row = 1,column=1)
def selectLogFile(self):
filename = askopenfilename()
self.logFilePath.set(filename)
def selectImageFile(self):
imageFolder = askdirectory()
self.imageFilePath.set(imageFolder)
root = Tk()
root.title("Geo Tagging")
root.geometry("600x100")
app = Application(root)
root.mainloop()

There are many ways to tackle a problem like this. There are many ways to do this. I'm going to give you the most simple solution to this question I know. When changing the text of a label or any kind of wiget really. I would do it like this.
Name_Of_Label["text"] = "Your New Text"
So when I apply this knowledge to your code. It would look something like this.
from tkinter import*
class MyGUI:
def __init__(self):
self.__mainWindow = Tk()
#self.fram1 = Frame(self.__mainWindow)
self.labelText = 'Enter amount to deposit'
self.depositLabel = Label(self.__mainWindow, text = self.labelText)
self.depositEntry = Entry(self.__mainWindow, width = 10)
self.depositEntry.bind('<Return>', self.depositCallBack)
self.depositLabel.pack()
self.depositEntry.pack()
mainloop()
def depositCallBack(self,event):
self.labelText["text"] = 'change the value'
print(self.labelText)
myGUI = MyGUI()
If this helps please let me know!

Python function returns PY_VAR1 unexpectedly

I am expecting my button function to print a number (minutes_selected) based on the current value of the Spinner UI element, but the variable is always PY_VAR1:
from tkinter import *
from tkinter import ttk
def get_minutes():
global minutes_selected
minutes_selected.get()
print(mintes_selected)
root = Tk()
minutes_selected = StringVar()
minutes_spinbox = Spinbox(root, from_ = 1, to = 1440, textvariable = minutes_selected).pack()
Is there some basic misunderstanding with regards to how variables can be access from within a function?

You need to use the get method to get the value of the variable.
Change this:
print(mintes_selected)
To this:
print(minutes_selected.get())