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Tkinter PopUp window not taking the textvariable values from Entry and Combobox

I used Tkinter in Python3 to create a GUI and one of the functions is a pop up window after a button click. This is how my popup window looks like this. The pop up window will take the user inputs and update a variable from the class object (self). Everything works fine except the part in the function UpdateValues() as shown in the code below.
After inputting and updating the Frequency (variable freq in the code) and Iterations (variable loop in code) values in the popup window, they fail to print on the terminal and give a blank screen. Thus the self.freq and self.loop are unable to get updated.
I'm a newbie to python-classes and tkinter and have been struggling with this problem for a while now. Any help will be much appreciated. Thank you!
CODE:
'''Class and other attributes here'''
# Blinking light ssh command
self.freq = "500"
self.loop = "10"
def RunCode():
cmd = "sshpass -p \"raspberry\" ssh -to StrictHostKeyChecking=no pi#pi ./led "+self.freq+" "+self.loop
os.system(cmd)
def PopUpBox1():
popup = tk.Tk()
popup.title("Edit Parameters")
w = 325
h = 75
x = (ws/2) - w/2
y = (hs/2) - h/2
popup.geometry('%dx%d+%d+%d' % (w,h,x,y))
popup.resizable(False,False)
# Adding widgets to PopUpBox
# Modified Button Click Function for Update
def UpdateValues():
update.configure(text='Updated')
print(freq.get())
print(loop.get())
self.freq = str(freq.get())
self.loop = str(loop.get())
popup.destroy()
# Frequency and Iterations label
ttk.Label(popup, text="Frequency:",font='200').grid(column=0, row=0, padx=4, pady=4, sticky='w')
ttk.Label(popup, text="Iterations:",font='200').grid(column=1, row=0, padx=4, pady=4, sticky='w')
# Adding a Textbox Entry widget for frequency values
freq = tk.StringVar()
name_entered = tk.Entry(popup, width=12, textvariable=freq)
name_entered.grid(column=0, row=1, padx=4, pady=4)
# Adding a Combobox for iteration values
loop = tk.StringVar()
number_chosen = ttk.Combobox(popup, width=12, textvariable=loop)
number_chosen['values'] = (1, 2, 4, 42, 100)
number_chosen.grid(column=1, row=1, padx=4, pady=4)
number_chosen.current(0)
# Adding a Button for Updation
update = ttk.Button(popup, text="Update", command = UpdateValues)
update.grid(column=2, row=1, padx=4, pady=4)
# Place cursor into name Entry
name_entered.focus()

Using Python with Tkinter, how can I make a button press do a different thing depending on which option is selected in the option menu?

I'm making a simple GUI, and my goal right now is for the user to select an option (kinematics or electricity) and then they would press the button to move on to a new screen for the one they selected. Currently, the button will do the same thing no matter which is selected, and I don't know how to change that. I'm using Python 3.6.1
from tkinter import *
import tkinter.font
bg_color1 = "#008B8B"
abc = Tk()
abc.title("Physics Problem Solver")
abc.rowconfigure(0, weight=1)
abc.columnconfigure(0, weight=1)
helvetica_bold_16 = tkinter.font.Font(
root = abc,
family="Helvetica",
weight="bold",
size=16)
helvetica_bold_12 = tkinter.font.Font(
root = abc,
family="Helvetica",
weight="bold",
size=12)
app = Frame(abc,
bd=6,
relief="groove",
bg=bg_color1)
app.rowconfigure(0, weight=1)
app.columnconfigure(0, weight=1)
app.grid(sticky=N+S+E+W)
msg1 = Message(app,
text = "Welcome to the Physics Problem Solver!",
font=helvetica_bold_16,
bg=bg_color1,
fg="white",
justify="center",
relief="flat")
msg1.grid(pady=15)
def callback1():
toplevel = Toplevel()
toplevel.title("Window 2")
toplevel.focus_set()
optionList = ("Kinematics",
"Electricity")
om1v= StringVar()
om1v.set(optionList[0])
om1 = OptionMenu(app,
om1v,
"Kinematics",
"Electricity")
om1.grid(pady=20)
b1= Button(app,
text="Go!",
width=5,
activebackground="#007070",
activeforeground="#00ACAC",
fg="black",
justify="center",
font=helvetica_bold_12,
relief="raised",
command=callback1)
b1.grid(pady=20)
abc.mainloop()

There's nothing special you need to do. In your callback you can get the value of the option menu and then do whatever is appropriate.
def callback1():
if om1v.get() == "Kinematics":
do_kinematics
else:
do_electricity()

Set Entry widget values dynamically in Tkinter

I have a window to browse a folder containing necessary files. I am using tkFileDialog for the same. I want to set the value of Entry widget equal to this selected folder. Initially when no folder is selected it will be null. As soon as I select the folder, the path of the selected folder should appear in the Entry widget. The user should be able to modify.Below mentioned is the code for the same.
from Tkinter import *
from tkFileDialog import *
class Checkit:
root = Tk()
#default string to be displayed in the entry of path
path_to_file = StringVar(root, value="abc")
def __init__(self):
self.inputDetail()
def inputDetail(self):
#copy the root window
master = self.root
#create frame for details in the root window
details_frame = Frame(master)
details_frame.grid(row=0, column=0)
#Create the Labels
papercode_label = Label(details_frame, text="Paper code:")
subject_label = Label(details_frame, text="Subject:")
chapter_label = Label(details_frame, text="Chapter:")
batch_label = Label(details_frame, text="Batch:")
ansFolder_label = Label(details_frame, text="Folder containing answer-keys:")
#create entry for the labels
papercode_entry = Entry(details_frame)
subject_entry = Entry(details_frame)
chapter_entry = Entry(details_frame)
batch_entry = Entry(details_frame)
ansFolder_entry = Entry(details_frame)
#create button to add path
path = Button(details_frame, text="Browse", command= lambda: self.addpath(details_frame))
#button to enter the next window
next = Button(details_frame, text="Next", command= lambda: self.checkOmr(details_frame, master))
#Use grid layout to place labels and entry
papercode_label.grid(row=0, sticky=W)
papercode_entry.grid(row=1, sticky=W)
subject_label.grid(row=2, sticky=W)
subject_entry.grid(row=3, column=0, sticky=W)
chapter_label.grid(row=4, sticky=W)
chapter_entry.grid(row=5, column=0, sticky=W)
batch_label.grid(row=6, sticky=W)
batch_entry.grid(row=7, column=0, sticky=W)
ansFolder_label.grid(row=8, sticky=W)
path.grid(row=9, sticky=W, columnspan=2)
next.grid(row=10, sticky=E, columnspan=2)
master.mainloop()
def checkOmr(self, old_frame, master):
#destoy the old frame
old_frame.destroy()
#create frame for details in the root window
inputPath_frame = Frame(master)
inputPath_frame.grid(row=0, column=0)
#create label to input folder containing
omrFolder_label = Label(inputPath_frame, text="Folder containing OMR sheet to be checked:")
#create button to add path
path = Button(inputPath_frame, text="Browse", command= lambda: self.addpath(inputPath_frame))
selected_path = Entry(inputPath_frame, textvariable=self.path_to_file)
#place the label and button on the grid
omrFolder_label.grid(row=0, sticky=W)
path.grid(row=1, column=0, sticky=W)
selected_path.grid(row=1, column=1, sticky=W)
#master.mainloop()
def addpath(self, details_frame):
self.path_to_file = askdirectory(parent=details_frame,initialdir="/",title='Please select a directory')
if __name__=='__main__':
handle = Checkit()
Here I am trying to change the modifying the self. path_to_file value on the click of the button. I tried to print the value of self.path_to_file value in addpath(). It gives correct result there but the value in the Entry selected_path in checkOMR() does not modify.
Can somebody suggest what changes should I make to make that thing possible.

Look at this line:
self.path_to_file = askdirectory(...)
Before this line of code runs, self.path_to_file is an instance of a StringVar. After this line of code has run, self.path_to_file is reset to be just a string.
Assuming you want self.path_to_file to remain an instance of StringVar, you need to change that line to this:
path = askdirectory(...)
self.path_to_file.set(path)

Tkinter. Press Enter in Entry box. Append to Text box. How?

I am making a chat program and decided to use Tkinter for the interface.
What I wanna do is a breeze in C# but Tkinter is new to me.
Basically I have a form with a Entry control and a Text control.
I want to know how to append text from the Entry control to the Text control after the user presses Enter.
Here's my code so far:
from tkinter import *
class Application:
def hello(self):
msg = tkinter.messagebox.askquestion('title','question')
def __init__(self, form):
form.resizable(0,0)
form.minsize(200, 200)
form.title('Top Level')
# Global Padding pady and padx
pad_x = 5
pad_y = 5
# create a toplevel menu
menubar = Menu(form)
#command= parameter missing.
menubar.add_command(label="Menu1")
#command= parameter missing.
menubar.add_command(label="Menu2")
#command= parameter missing.
menubar.add_command(label="Menu3")
# display the menu
form.config(menu=menubar)
# Create controls
label1 = Label(form, text="Label1")
textbox1 = Entry(form)
#command= parameter missing.
button1 = Button(form, text='Button1')
scrollbar1 = Scrollbar(form)
textarea1 = Text(form, width=20, height=10)
textarea1.config(yscrollcommand=scrollbar1.set)
scrollbar1.config(command=textarea1.yview)
textarea1.grid(row=0, column=1, padx=pad_x, pady=pad_y, sticky=W)
scrollbar1.grid(row=0, column=2, padx=pad_x, pady=pad_y, sticky=W)
textbox1.grid(row=1, column=1, padx=pad_x, pady=pad_y, sticky=W)
button1.grid(row=1, column=2, padx=pad_x, pady=pad_y, sticky=W)
form.mainloop()
root = Tk()
Application(root)

So you're using a tkinter.Text box, which supports the .insert method. Let's use it!
def __init__(self,form):
# Lots of your code is duplicated here, so I'm just highlighting the main parts
button1 = Button(form, text='Button1', command = self.addchat)
self.textbox = textbox1 # to make it accessible outside your __init__
self.textarea = textarea1 # see above
form.bind("<Return>", lambda x: self.addchat())
# this is the magic that makes your enter key do something
def addchat(self):
txt = self.textbox.get()
# gets everything in your textbox
self.textarea.insert(END,"\n"+txt)
# tosses txt into textarea on a new line after the end
self.textbox.delete(0,END) # deletes your textbox text

How to control the tkinter combobox selection highlighting

I wrote a small farad converter to learn GUI programming. It works great, looks fine-ish. The only problem is I can't seem to figure out how to control this strange highlighting that comes up on my ttk.Combobox selections. I did use a ttk.Style(), but it only changed the colors of the ttk.Combobox background, entries, etc. I also tried changing openbox/gtk themes.
I'm talking about what's seen there on the text "microfarads (uF)".
It'd be fine, if it highlighted the entire box; but I'd rather have it gone completely.
How can I manipulate a ttk.Combobox's selection highlight?
# what the farad?
# thomas kirkpatrick (jtkiv)
from tkinter import *
from tkinter import ttk
# ze la programma.
def conversion(*args):
# this is the numerical value
inV = float(inValue.get())
# these two are the unit (farads, microfarads, etc.) values
inU = inUnitsValue.current()
outU = outUnitsValue.current()
# "mltplr" is multiplied times inValue (inV)
if inU == outU:
mltplr = 1
else:
mltplr = 10**((outU - inU)*3)
outValue.set(inV*mltplr)
# start of GUI code
root = Tk()
root.title("What the Farad?")
# frame
mainFrame = ttk.Frame(root, width="364", padding="4 4 8 8")
mainFrame.grid(column=0, row=0)
# input entry
inValue = StringVar()
inValueEntry = ttk.Entry(mainFrame, width="20", justify="right", textvariable=inValue)
inValueEntry.grid(column=1, row=1, sticky="W")
# input unit combobox
inUnitsValue = ttk.Combobox(mainFrame)
inUnitsValue['values'] = ('kilofarads (kF)', 'farads (F)', 'millifarads (mF)', 'microfarads (uF)', 'nanofarads (nF)', 'picofarads (pF)')
inUnitsValue.grid(column=2, row=1, sticky="e")
inUnitsValue.state(['readonly'])
inUnitsValue.bind('<<ComboboxSelected>>', conversion)
# result label
outValue = StringVar()
resultLabel = ttk.Label(mainFrame, textvariable=outValue)
resultLabel.grid(column=1, row=2, sticky="e")
# output unit combobox
outUnitsValue = ttk.Combobox(mainFrame)
outUnitsValue['values'] = ('kilofarads (kF)', 'farads (F)', 'millifarads (mF)', 'microfarads (uF)', 'nanofarads (nF)', 'picofarads (pF)')
outUnitsValue.grid(column=2, row=2, sticky="e")
outUnitsValue.state(['readonly'])
outUnitsValue.bind('<<ComboboxSelected>>', conversion)
# padding for widgets
for child in mainFrame.winfo_children(): child.grid_configure(padx=4, pady=4)
# focus
inValueEntry.focus()
# bind keys to convert (auto-update, no button)
root.bind('<KeyRelease>', conversion)
root.mainloop()

Could it be that with a readonly combobox the problem is not the selection but the relatively strong focus-indicator?
With this workarround you lose the ability to control your program by keyboard. To do it right you would have to change the style of the focus-highlighting.
from tkinter import *
from ttk import *
def defocus(event):
event.widget.master.focus_set()
root = Tk()
comboBox = Combobox(root, state="readonly", values=("a", "b", "c"))
comboBox.grid()
comboBox.set("a")
comboBox.bind("<FocusIn>", defocus)
mainloop()

You can use the Combobox's selection_clear() method to clear the selection whenever you want.
e.g
inUnitsValue.selection_clear()

Just refresh the selected value of the Combobox.
This will help for removing the highlight.
import tkinter.ttk
import tkinter
items = ["test1","test2","test3","test4"]
class TkCombobox(tkinter.ttk.Combobox):
def __init__(self, *arg, **kwarg):
super(TkCombobox, self).__init__(*arg, **kwarg)
self._strvar_ = tkinter.StringVar()
self._strvar_.set("")
self["textvariable"] = self._strvar_
self.bind("<<ComboboxSelected>>", self.highlight_clear)
def highlight_clear(self, event):
current = self._strvar_.get()
self.set("")
self.set(current)
master = tkinter.Tk();master.geometry("400x400")
c = TkCombobox(master, values=items, state="readonly")
c.pack()
master.mainloop()