Python 3
I want to create a Tkinter label with a handle name that is passed from a function. For example, if the variable name is 'hotdog', I want to create a label that is called 'hotdogLabel', that displays the value of hotdog. I made a function that creates the label, but I dont know how to script the variable input. This does not work
def makeLabel(labelname,width,gridx,gridy,px,py):
name=labelname+'label'
name =Label(window,text=labelname,width=width).grid(row=gridx,column=gridy,padx=px,pady=py)
window = tk.Tk()
makeLabel('FOOBAR',25,1,2,5,5)
window.mainloop()
You didn't assign the value to text you used the old value.
def makeLabel(labelname,width,gridx,gridy,px,py):
name=labelname+'label'
name =Label(window,text=name,width=width).grid(row=gridx,column=gridy,padx=px,pady=py)
window = tk.Tk()
makeLabel('FOOBAR',25,1,2,5,5)
window.mainloop()
The best solution I could think of is to use a dictionary to store a key with the name you want, and the corresponding Label object.
Building on top of your example:
def main():
def makeLabel(labeltext,width,gridx,gridy,px,py):
# dynamically created label name
labelname=labeltext+'label'
# creates Label object and store reference to it in 'label'
label = tk.Label(window, text=labelname,width=width)
# places label on grid
label.grid(row=gridx,column=gridy,padx=px,pady=py)
# returns tuple with label name and Label object
return (labelname, label)
window = tk.Tk()
# initialize dictionary
labelDictionary = {}
# newLblEntry will receive a tuple ('FOOBARlabel', <reference to Label object>)
newLblEntry = makeLabel('FOOBAR',25,1,2,5,5)
# store Label object with the key 'FOOBARlabel'
labelDictionary[newLblEntry[0]] = newLblEntry[1]
window.mainloop()
By doing this, when you need to get the Label created above, simply do Label label = labelDictionary['FOOBARlabel'].
Good link for more on python dictionaries:
http://www.compciv.org/guides/python/fundamentals/dictionaries-overview
Related
I'm working on a project and i would like to get the Value of an Entry created in a def (turned on by a button on Tkinter)
So I have my main tkinter menu, with a button which will call the def "panier".
The def "panier" is creating the Entry "value" and another button to call a second def "calcul".
The second def "calcul" will do things with the value of Entry...
But then, in the def "calcul", when i'm trying to do value.get() it tells "NameError: name 'value' is not defined"
Here is the code, btw the Entry must be created by the def...
from tkinter import *
def panier():
value=Entry(test)
value.pack()
t2=Button(test,text="Validate",command=calcul)
t2.pack()
def calcul(value):
a=value.get()
#here will be the different calculations I'll do
test=Tk()
t1=Button(test,text="Button",command=panier)
t1.pack()
test.mainloop()
Appreciate every feedback :)
You can make the variable global like this:
from tkinter import *
def panier():
global value
value = Entry(test)
value.pack()
t2 = Button(test, text="Validate", command=calcul)
t2.pack()
def calcul():
a = value.get()
print(a)
#here will be the different calculations I'll do
test = Tk()
t1 = Button(test, text="Button", command=panier)
t1.pack()
test.mainloop()
The global value line makes the variable global so you can use it anywhere in your program.
You can also pass in the variable as an argument like what #JacksonPro suggested
t2 = Button(test, text="Validate", command=lambda: calcul(value))
This is one way to do it. Globally create a collection (list or dictionary) to hold a reference to the Entry. When you create the Entry, add it to the collection. I made it with either a list or dictionary for holding the references, so toggle the commented variations in all three places to try it both ways.
import tkinter as tk
def panier():
for item in ('value', ):
ent = tk.Entry(test)
collection.append(ent)
# collection[item] = ent
ent.pack()
t2 = tk.Button(test,text="Validate",command=calcul)
t2.pack()
def calcul():
a = collection[0].get()
# a = collection['value'].get()
print(a)
collection = []
# collection = {}
test = tk.Tk()
t1 = tk.Button(test, text="Button", command=panier)
t1.pack()
test.mainloop()
I have a dynamically created Tkinter checkbutton widget, which takes in the contents of a list of usernames. I then displayed those names with a checkbox alongside.
What I need to do is obviously collect which usernames have been checked, so I can pass that off to another function to action.
How should I write the variable part of this so it creates a new list of chosen usernames?
What I have thus far:
def delprof_results(users_delprof):
for i in range(len(users_delprof)):
c = Checkbutton(resultsFrame, text=users_delprof[i], variable=users_delprof[i])
c.pack(anchor=W)
def delprof_del():
users_chosen = []
print str(users_delprof[i]).get() # Works up until this point. How to get individual variable with ID.
del_but = Button(resultsFrame, text="Delete", width=7, height=1, command=delprof_del)
del_but.pack(side=LEFT)
Thanks in advance,
Chris.
If you want to reach individual objects, simply keep a reference to the individual objects instead of creating objects while overwriting the same variable with each iteration of a loop like:
for i in range(30):
a = i
How to reach a's state where it was 13? Well, you can't as it's overwritten.
Instead, use collection types. In the example below I used dict:
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
def upon_select(widget):
print("{}'s value is {}.".format(widget['text'], widget.var.get()))
if __name__ == '__main__':
root = tk.Tk()
names = {"Chester", "James", "Mike"}
username_cbs = dict()
for name in names:
username_cbs[name] = tk.Checkbutton(root, text=name,
onvalue=True, offvalue=False)
username_cbs[name].var = tk.BooleanVar()
username_cbs[name]['variable'] = username_cbs[name].var
username_cbs[name]['command'] = lambda w=username_cbs[name]: \
upon_select(w)
username_cbs[name].pack()
tk.mainloop()
You could make a list of values from the checkbuttons:
values = []
for i in range(len(users_delprof)):
v = IntVar()
c = Checkbutton(master, text="Don't show this again", variable=v)
c.var = v
values.append(v)
Now you can check the value by looking in the list values, and getting the value of a checkbutton with v.get().
I would like to sort numbers when I clicked sort numbers Radiobutton. I already achieve this by calling a function when the Radiobutton is clicked. however, i couldn't sort numbers without calling a function.
this is my code
R1=Radiobutton(root,text="Sort Student Numbers",value=1)
R1.pack(anchor=W)
R2=Radiobutton(root,text="Sort Student Names",value=2)
R2.pack(anchor=W)
with open("student.json", "r"") as f:
data = json.load(f)
for d in data["student"]:
if value == 1:
data["student"].sort(key = lambda d: d["Numbers"])
elif value == 2:
data["student"].sort(key = lambda d: d["Names"])
label_1 = Label(frame , text="Name: %s" %(d["Names"]))
label_1.pack()
label_2 = Label(frame , text="Student Numbers: %d" %(d["Numbers"]))
label_2.pack()
if I say for example R1=Radiobutton(root,text="Sort Student Numbers",value=1, command = sorted_numbers(1)) everything works fine but the reason I don't want to use function calling is I would have to create 3 functions to achieve what I want. thanks
One way to solve this problem is to tie these radio buttons to a shared tkinter variable instance. When a radio button is selected, the value of the variable will be set to the value of the radio button, and then you can use that value in your code.
I haven't had time to test this code, but I have copied your code and modified it in a way that should work. This code assumes that you are importing everything from tkinter, using the line from tkinter import *; otherwise, you will need to do something like from tkinter import IntVar. There are several types of tkinter variable subclasses (IntVar, BooleanVar, etc.), and each has the methods get and set, which behave exactly as you'd expect (as demonstrated below).
# This is the variable that will store the value of the currently selected radio button
sort_value = IntVar()
# For each radio button, assign sort_value to the keyword parameter "variable"
R1=Radiobutton(root,text="Sort Student Numbers",variable=sort_value,value=1)
R1.pack(anchor=W)
R2=Radiobutton(root,text="Sort Student Names",variable=sort_value,value=2)
R2.pack(anchor=W)
with open("student.json", "r") as f:
data = json.load(f)
for d in data["student"]:
# sort_value is an IntVar, so sort_value.get returns a Python int
if sort_value.get() == 1:
data["student"].sort(key = lambda d: d["Numbers"])
elif sort_value.get() == 2:
data["student"].sort(key = lambda d: d["Names"])
label_1 = Label(frame , text="Name: %s" %(d["Names"]))
label_1.pack()
label_2 = Label(frame , text="Student Numbers: %d" %(d["Numbers"]))
label_2.pack()
Edit: Like Nae pointed out in the comments, you can also initialize the variable to a default value like this:
sort_value = IntVar(value=1)
Otherwise, its default value will be 0. I believe that by setting it to 1, this will also cause the radio button whose value is 1 to be selected by default.
I hope this helps.
I'm currently creating a GUI in order to turn a lot of individual instruments into one complete system. In def smuSelect(self) I create a list self.smuChoices I can use to call individual choices such as smuChoices[0] and it will return "2410(1)".
Once I call def checkBoxSetup it returns PY_VARxxx. I've tried searching the different forums and everything. I've seen mentions using the .get() which just gives me the state of the individual choice. The reason I want the actual string itself is I would like to use it in def testSetup(self) for the user to assign specific names to the individual machine, for example, 2410 = Gate.
My initial attempt was to create another variable smuChoice2 but I believe this is still changing the original list self.smuChoices.
import tkinter as tk
import numpy as np
from tkinter import ttk
def checkBoxSetup(smuChoice2): #TK.INTVAR() IS CHANGING NAME OF SMUS NEED TO CREATE ANOTHER INSTANCE OF SELF.SMUCHOICES
for val, SMU in enumerate(smuChoice2):
smuChoice2[val] = tk.IntVar()
b = tk.Checkbutton(smuSelection,text=SMU,variable=smuChoice2[val])
b.grid()
root = tk.Tk()
root.title("SMU Selection")
"""
Selects the specific SMUs that are going to be used, only allow amount up to chosen terminals.
--> If only allow 590 if CV is picked, also only allow use of low voltage SMU (maybe dim options that aren't available)
--> Clear Checkboxes once complete
--> change checkbox selection method
"""
smuChoices = [
"2410(1)",
"2410(2)",
"6430",
"590 (CV)",
"2400",
"2420"
]
smuChoice2 = smuChoices
smuSelection = ttk.Frame(root)
selectInstruct = tk.Label(smuSelection,text="Choose SMUs").grid()
print(smuChoices[0]) #Accessing list prior to checkboxsetup resulting in 2410(1)
checkBoxSetup(smuChoice2)
print(smuChoices[0]) #Accessing list after check box setup resulting in PY_VAR376
variableSMUs = tk.StringVar()
w7_Button = tk.Button(smuSelection,text="Enter").grid()
w8_Button = tk.Button(smuSelection,text="Setup Window").grid()
root.mainloop()
I was able to solve the problem by changing my list, smuChoices, to a dictionary then modifying
def checkBoxSetup(smuChoice2):
for val, SMU in enumerate(smuChoice2):
smuChoice2[val] = tk.IntVar()
b = tk.Checkbutton(smuSelection,text=SMU,variable=smuChoice2[val])
b.grid()
to
def checkBoxSetup(self):
for i in self.smuChoices:
self.smuChoices[i] = tk.IntVar()
b = tk.Checkbutton(self.smuSelection,text=i,variable=self.smuChoices[i])
b.grid()
Previously I was replacing the variable with what I'm guessing is some identifier that tkinter uses to store the state which is why I was getting PYxxx.
First of all getting PY_VARXX instead of what's in a variable class indicates the lack of get().
replace:
print(self.smuChoices[0])
with:
print(self.smuChoices[0].get())
Secondly, if you want to display the value of a variable class on a label, button, etc. you could rather just use the textvariable option by simply assigning the variable class to it.
Replace:
tk.Label(self.smuName,text=SMU).grid()
with:
tk.Label(self.smuName, textvariable=self.smuChoices[val]).grid()
Your question is still a bit unclear to me but I will try to provide an answer to the best of my understanding.
As I understand it, you're trying to create a set of Checkbuttons for a given list of items. Below is an example of a method that takes items as an argument and returns a dictionary of checkboxes that have root as their parent:
import tkinter as tk
def dict_of_cbs(iterable, parent):
if iterable:
dict_of_cbs = dict()
for item in iterable:
dict_of_cbs[item] = tk.Checkbutton(parent)
dict_of_cbs[item]['text'] = item
dict_of_cbs[item].pack() # it's probably a better idea to manage
# geometry in the same place wherever
# the parent is customizing its
# children's layout
return dict_of_cbs
if __name__ == '__main__':
root = tk.Tk()
items = ("These", "are", "some", "items.")
my_checkboxes = dict_of_cbs(items, root)
root.mainloop()
Additionally note that I haven't used any variable classes (BooleanVar, DoubleVar, IntVar or StringVar) as they seem to be redundant in this particular case.
checkLabel = ttk.Label(win,text = " Check Amount ", foreground = "blue")
checkLabel.grid(row = 0 , column = 1)
checkEntry = ttk.Entry(win, textvariable = checkVariable)
checkEntry.grid(row = 1, column = 1, sticky = 'w')
How do I change the defualt entry field from displaying 0?
Use the entry widget's function, .insert() and .delete(). Here is an example.
entry = tk.Entry(root)
entry.insert(END, "Hello") # this will start the entry with "Hello" in it
# you may want to add a delay or something here.
entry.delete(0, END) # this will delete everything inside the entry
entry.insert(END, "WORLD") # and this will insert the word "WORLD" in the entry.
Another way to do this is with the Tkinter StrVar. Here is an example of using the str variable.
entry_var = tk.StrVar()
entry_var.set("Hello")
entry = tk.Entry(root, textvariable=entry_var) # when packing the widget
# it should have the world "Hello" inside.
# here is your delay or you can make a function call.
entry_var.set("World") # this sets the entry widget text to "World"
Set the value of checkVariable to '' (the empty string) before you create the Entry object? The statement to use would be
checkVariable.set('')
But then checkVariable would have to be a StringVar, and you would have to convert the input value to an integer yourself if you wanted the integer value.