So I am currently trying to create a button on a GUI that will let the user generate a new entry field.
I have no idea how to do this. I'm guessing that it will require a lambda function, but apart from that, I have no idea.
Here's the basic code I have so far:
from tkinter import *
class prac:
def autoAddWidget(self,frame,x,y):
self.entryField = Entry(frame,text="Entry Field")
self.entryField.grid(row=x, column=y)
#lambda function?
def __init__(self, master):
frame = Frame(master, width=60, height=50)
frame.pack()
x=1
self.addWidgetButton = Button(frame, text="Add new widget", command=self.autoAddWidget(frame, x,0))
self.addWidgetButton.grid(row=0, column=0)
x+=1
root = Tk()
app = prac(root)
root.mainloop()
Would appreciate the help.
Thanks
You're passing to the command argument result from the method self.autoAddWidget(frame, x,0) not method itself. You have to pass there a reference to a callable object, a function that will be called when the event occurs. Please check a documentation next time before you ask the question.
Ok, I fixed the code, now it works:
from tkinter import *
class Prac:
def autoAddWidget(self):
self.entryField = Entry(self.frame,text="Entry Field")
self.entryField.grid(row=self.x, column=0)
self.x+=1
def __init__(self, master):
self.frame = Frame(master, width=60, height=50)
self.frame.pack()
self.x=1
self.addWidgetButton = Button(self.frame, text="Add new widget", command=self.autoAddWidget)
self.addWidgetButton.grid(row=0, column=0)
root = Tk()
app = Prac(root)
root.mainloop()
Related
I feel like I've scoured the web for an eternity, rephrased my question a thousand times for something I feel like should be very simple.
I wonder if there is a way to check if a Tkinter Widget is active (not greyed out / disabled). I have a set of OptionMenus that start out disabled, and are configured to state=ACTIVE when they click a checkbox, so that the user can select which OptionMenus they want to use.
When I try to "submit" the fields in the OptionMenus, I only want the ones that are ACTIVE. I already tried if OptionMenu.state == ACTIVE but then I get an error that OptionMenu has no attribute state, even though I configure that earlier.
Here is a sample of my code:
from tkinter import *
class Application(Frame):
# Initializing the window and the required variables
def __init__(self, master=None):
Frame.__init__(self, master)
self.checkbox_in_use = BooleanVar(self, False)
self.checkbox = Checkbutton(self, text="check",
var=self.checkbox_in_use,
command=self.check_change
self.checkbox.grid(row=0, column=1, sticky='W')
self.menu = OptionMenu(title_setting,
"Menu",
"Menu",
["Menu1", "Menu2"])
self.menu.grid(row=1, column=1)
self.menu.config(state=DISABLED)
submit = Button(self, text="submit",
command=self.submit_function)
submit.grid(row=2, column=0)
self.master = master
self.init_window()
# Initialize the window
def init_window(self):
self.master.title("Example")
self.pack(fill=BOTH, expand=1)
def check_change(self):
if self.checkbox_in_use.get():
self.menu.config(state=ACTIVE)
else:
self.menu.config(state=DISABLED)
def submit_function(self):
# This is the part I want to do something with.
if self.menu.state == ACTIVE:
print("You are good to go! Do the stuff.")
root = Tk()
root.geometry("400x300")
app = Application(root)
root.mainloop()
Thank you for all responses.
All you need is cget() for this. self.menu.cget('state') will do the trick.
That said I want to point out some other things in your code.
You Application class already has an __init__ at the start so why use:
# Initialize the window
def init_window(self):
self.master.title("Example")
self.pack(fill=BOTH, expand=1)
You really should not pack the frame from inside the frame class but rather when calling the class. Also pack wont work here it will throw an error. Do this instead: app = Application(root).grid().
Take a look at the reformatted example below (with cget()).
from tkinter import *
class Application(Frame):
def __init__(self, master=None):
Frame.__init__(self, master)
self.master.title("Example")
self.checkbox_in_use = BooleanVar(self, False)
self.checkbox = Checkbutton(self, text="check", var=self.checkbox_in_use, command=self.check_change)
self.checkbox.grid(row=0, column=1, sticky='W')
self.menu = OptionMenu(master,"Menu","Menu",["Menu1", "Menu2"])
self.menu.grid(row=1, column=1)
self.menu.config(state=DISABLED)
Button(self, text="submit", command=self.submit_function).grid(row=2, column=0)
def check_change(self):
if self.checkbox_in_use.get():
self.menu.config(state=ACTIVE)
else:
self.menu.config(state=DISABLED)
def submit_function(self):
print(self.menu.cget('state'))
root = Tk()
root.geometry("400x300")
app = Application(root).grid()
root.mainloop()
Learning to use Tkinter and following an online tutorial. This is an example given where text is entered and then label will update accordingly to the input text field.
I'm trying it in Python3 on Mac and on Raspberry Pi and I don't see the effect of trace, hence the label doesn't get modified by the Entry. Any help would be appreciate (or any other simple example of how to use Entry and Trace together)
Thanks.
from tkinter import *
class HelloWorld:
def __init__(self, master):
frame = Frame(master)
frame.pack()
self.button = Button(
frame, text="Hello", command=self.button_pressed
)
self.button.pack(side=LEFT, padx=5)
self.label = Label(frame, text="This is a label")
self.label.pack()
a_var = StringVar()
a_var.trace("w", self.var_changed)
self.entry = Entry(frame,textvariable=a_var)
self.entry.pack()
def button_pressed(self):
self.label.config(text="I've been pressed!")
def var_changed(self, a, b, c):
self.label.config(text=self.entry.get())
def main():
root = Tk()
root.geometry("250x150+300+300")
ex = HelloWorld(root)
root.mainloop()
if __name__ == '__main__':
main()
The problem is that you are using a local variable for a_var, and on the Mac it is getting garbage-collected. Save a reference to the variable (eg: self.a_var rather than just a_var).
self.a_var = StringVar()
self.a_var.trace("w", self.var_changed)
self.entry = Entry(frame,textvariable=self.a_var)
self.entry.pack()
Note: if all you want is to keep a label and entry in sync, you don't need to use a trace. You can link them by giving them both the same textvariable:
self.entry = Entry(frame, textvariable=self.a_var)
self.label = Label(frame, textvariable=self.a_var)
I'm just getting started coding in Python/Tkinter for a small Pymol plugin. Here I'm trying to have a toggle button and report its status when it is clicked. The button goes up and down, but toggleAVA never gets called. Any ideas why?
from Tkinter import *
import tkMessageBox
class AVAGnome:
def __init__(self, master):
# create frames
self.F1 = Frame(rootGnome, padx=5, pady=5, bg='red')
# checkbuttons
self.AVAselected = IntVar()
self.AVAselected.trace("w", self.toggleAVA)
self.AVAbutton = Checkbutton(self.F1, text='AVA', indicatoron=0, variable=self.AVAselected)
# start layout procedure
self.layout()
def layout(self):
self.F1.pack(side=TOP, fill=BOTH, anchor=NW)
#entry and buttons
self.AVAbutton.pack(side=LEFT)
def toggleAVA(self, *args):
if (self.AVAselected.get()):
avastatus = "selected"
else:
avastatus = "unselected"
tkMessageBox.showinfo("AVA status", avastatus)
def __init__(self):
open_GnomeUI()
def open_GnomeUI():
# initialize window
global rootGnome
rootGnome = Tk()
rootGnome.title('AVAGnome')
global gnomeUI
gnomeUI = AVAGnome(rootGnome)
I tested your code with Pymol.
Problem is because you use Tk() to create your window. You have to use Toplevel() and then it will work correctly with trace() or with command=.
Pymol is created with tkinter which can have only one window created with Tk() - it is main window in program. Every other window has to be created with Toplevel().
I have attached a working version of your code below. You can refer to it to learn where you went wrong. Generally, you have to mind how you structure your code if you are using a class format.This will help you visualize your code and debug better. You can read this discussion to help you.
from Tkinter import *
import tkMessageBox
class AVAGnome(Frame):
def __init__(self, parent):
Frame.__init__(self, parent)
# create frames
self.F1 = Frame(self, padx=5, pady=5, bg='red')
# checkbutton
self.AVAselected = IntVar()
self.AVAselected.trace("w", self.toggleAVA)
self.AVAbutton = Checkbutton(
self.F1, text='AVA', indicatoron=0, width=10,
variable=self.AVAselected)
# start layout procedure
self.F1.pack(side=TOP, fill=BOTH, anchor=NW)
self.AVAbutton.pack(side=LEFT) #entry and buttons
def toggleAVA(self, *args):
if (self.AVAselected.get()):
avastatus = "selected"
else:
avastatus = "unselected"
tkMessageBox.showinfo("AVA status", avastatus)
if __name__ == '__main__':
rootGnome = Tk()
rootGnome.title('AVAGnome')
gnomeUI = AVAGnome(rootGnome)
gnomeUI.pack(fill="both", expand=True)
gnomeUI.mainloop()
Update: The above code structure is for standalone tkinter programme. I am attempting to convert this working code to follow Pymol plugin example. Revised code is posted below and is susceptible to further revision.
# https://pymolwiki.org/index.php/Plugins_Tutorial
# I adapted from the example in the above link and converted my previous code to
#
from Tkinter import *
import tkMessageBox
def __init__(self): # The example had a self term here.
self.open_GnomeUI()
class AVAGnome(Frame):
def __init__(self, parent):
Frame.__init__(self, parent)
# create frames
self.F1 = Frame(self, padx=5, pady=5, bg='red')
# checkbutton
self.AVAselected = IntVar()
self.AVAselected.trace("w", self.toggleAVA)
self.AVAbutton = Checkbutton(
self.F1, text='AVA', indicatoron=0, width=10,
variable=self.AVAselected)
# start layout procedure
self.F1.pack(side=TOP, fill=BOTH, anchor=NW)
self.AVAbutton.pack(side=LEFT) #entry and buttons
def toggleAVA(self, *args):
if (self.AVAselected.get()):
avastatus = "selected"
else:
avastatus = "unselected"
tkMessageBox.showinfo("AVA status", avastatus)
# Note, I added a "self" term throughout function.
# Try w/ & w/o "self" to see which works.
def open_GnomeUI(self):
self.rootGnome = Tk()
self.rootGnome.title('AVAGnome')
self.gnomeUI = AVAGnome(self.rootGnome)
self.gnomeUI.pack(fill="both", expand=True)
self.gnomeUI.mainloop()
I'm just starting to learn to use tkinter with python and it seems counterintuitive that this attempt at a simple script to print whatever is entered into the entry box, doesn't work:
class App:
def __init__(self, master):
frame = Frame(master)
frame.pack()
text_write = Entry(frame)
text_write.pack()
self.button = Button(frame, text="quit", fg="red", command=frame.quit)
self.button.pack(side=LEFT)
self.hi_there = Button(frame, text='hello', fg='black', command=self.say_hi(text_write.get()))
self.hi_there.pack(side=RIGHT)
def say_hi(self, text):
print(text)
root = Tk()
app = App(root)
root.mainloop()
This does nothing and outputs no errors, but if I change it to this:
class App:
def __init__(self, master):
frame = Frame(master)
frame.pack()
self.text_write = Entry(frame)
self.text_write.pack()
self.button = Button(frame, text="quit", fg="red", command=frame.quit)
self.button.pack(side=LEFT)
self.hi_there = Button(frame, text='hello', fg='black', command=self.say_hi)
self.hi_there.pack(side=RIGHT)
def say_hi(self):
print(self.text_write.get())
then it calls the function and prints the value. Why does the 'self' need to be declared there? And why can't you pass the value of text_write as an argument to say_hi (as in the first example) and have it display? Or can you and I'm just doing it wrong?
When you do this:
self.button = Button(..., command=func())
then python will call func(), and the result of that will be assigned to the command attribute. Since your func doesn't return anything, command will be None. That's why, when you push the button, nothing happens.
Your second version seems fine. The reason self is required is that without it, text_write is a local variable only visible to to the init function. By using self, it becomes an attribute of the object and thus accessible to all of the methods of the object.
If you want to learn how to pass arguments similar to your first attempt, search this site for uses of lambda and functools.partial. This sort of question has been asked and answered several times.
I am trying to create frame with 2 input areas (for login and password) and confirmation button (after this button is pressed - code will read areas values). But I don't know how to do it inside class App without using some global function.
from Tkinter import *
class App:
def __init__(self, master):
frame_credentials = Frame(master, width=100, height=200)
frame_credentials.pack()
self.label_login = Label(frame_credentials, text='login')
self.text_login = Entry(frame_credentials, width=15)
self.label_pass = Label(frame_credentials, text='password')
self.text_pass = Entry(frame_credentials, show="*", width=15)
self.button_ok = Button(frame_credentials, text="Login")
self.label_login.grid(row=0, column=0)
self.text_login.grid(row=1, column=0)
self.label_pass.grid(row=2, column=0)
self.text_pass.grid(row=3, column=0)
self.button_ok.grid(row=0, column=1, rowspan=4)
self.button_ok.bind("<Button-1>", enter_in)
def enter_in(self):
print self.text_login, self.text_pass
root = Tk()
app = App(root)
root.mainloop()
Don't bind to <Button-1>; instead, use the command attribute and give it the name of a method in your object. For example:
class App:
def __init__(...):
...
self.button_ok = Button(..., command=self.enter_in)
...
def enter_in(self):
<put your login logic here>