I am playing around tkinter, and I was wondering if I had declared a method within an object, can I call it using the 'protocol' method of tkinter? or any function to be exact ie.
class Notepad():
...
...
def exit_func():
#Messagebox command warning 'You are exiting'
root = tk.Tk()
notepad = Notepad(root)
root.geometry("800x500")
root.mainloop()
#Problem is here
root.protocol("WM_DELETE_WINDOW", app.exit_func())
I tried this with my program, where my 'exit_func' had a 'get' function from tkinter and i got this error:
Traceback (most recent call last):
File "Notepad_with_console.py", line 204, in <module>
root.protocol("WM_DELETE_WINDOW", notepad.exit_file())
File "Notepad_with_console.py", line 175, in exit_file
if self.text.get(1.0,tk.END) != '' and self.current_file_dir == '':
File "C:\Anaconda\lib\tkinter\__init__.py", line 3246, in get
return self.tk.call(self._w, 'get', index1, index2)
_tkinter.TclError: invalid command name ".!text"
Is there a reason for this? Thanks!
root.protocol requires a reference to a function. Instead, you're immediately calling a function and then passing in the result.
Consider this code:
root.protocol("WM_DELETE_WINDOW", app.exit_func())
That code is functionally identical to this:
result = app.exit_func()
root.protocol("WM_DELETE_WINDOW", result)
Instead, you need to pass in a reference to the function:
root.protocol("WM_DELETE_WINDOW", app.exit_func)
Related
I'm getting an UnboundLocalError
Exception in Tkinter callback
Traceback (most recent call last):
File "C:\Program Files\WindowsApps\PythonSoftwareFoundation.Python.3.10_3.10.1264.0_x64__qbz5n2kfra8p0\lib\tkinter\__init__.py", line 1921, in __call__
return self.func(*args)
File "C:\Users\Ya Bish\Projects\Obracun Sati\main.py", line 249, in item_selected
app = EmpWindow(top,record)
UnboundLocalError: local variable 'record' referenced before assignment
when asking for filename and
def __init__(self,master):
self.master = master
self.openButton = Button(self.frame, text="Open",
command=self.openFile)
...
self.tree = Treeview(self.master, columns=self.columns, show="headings")
...
self.tree.bind('<<TreeviewSelect>>', self.item_selected)
def openFile(self):
...
self.tree.delete(*self.tree.get_children())
filename = filedialog.askopenfilename()
calc(filename)
for e in emps:
self.tree.insert('', END, values=e.treeValues)
while this Toplevel() window is either active or have been previously active.
def item_selected(self, event):
for selected_item in self.tree.selection():
item = self.tree.item(selected_item)
record = item['values'][0]
top = Toplevel()
app = EmpWindow(top,record)
top.mainloop()
EmpWindow is just a notebook class with two tabs defined and couple of labels so I don't think that code is necessary.
This may be an error with event and Bind but I don't understand that part at all so I don't even know how to approach it.
This might be happening because your for-loop in item_selected is not even getting a single iteration in which case record will never be defined. A simplified version of this is the following
def f():
for x in range(0):
print(x)
print(x)
f()
This gives the exact same error as your code. This kind of error occurs whenever you reference a variable before you assign it inside functions.
lbox = Listbox
def Show():
Selected=lbox.get(lbox.curselection())
with open("pass.json","r+") as jfile:
try:
data=json.load(jfile)
for i in data['Details']:
if Selected==i["Site"]:
password_text.set(i["Password"])
uname_text.set(i["Username"])
except JSONDecodeError:
pass
I wanted to use curselection() but curselection() missing 1 required positional argument: 'self' is coming all the time
lbox was declared in another function which is given below
def Show_fun():
newWindow=Toplevel(window)
newWindow.title("Show your stuff")
newWindow.geometry("600x400")
Label(newWindow,text="Show passwords").grid(row=0,column=1,pady=10)
Label(newWindow,text="Site name : ").grid(row=1,pady=10)
lbox=Listbox(newWindow)
lbox.grid(row=1,column=2)
sites=[]
with open("pass.json","r+") as jfile:
try:
data=json.load(jfile)
for i in data['Details']:
sites.append(i["Site"])
except JSONDecodeError:
pass
lbox.config(height=lbox.size())
for i in sites:
lbox.insert(lbox.size(),i)
#site_entry = Entry(newWindow,textvariable = site_text,width=20,state=DISABLED).grid(row=1,column=2)
Label(newWindow,text="Username : ").grid(row=2,pady=10)
uname_entry=Entry(newWindow,textvariable=uname_text,state=DISABLED).grid(row=2,column=2)
Label(newWindow,text="Password : ").grid(row=3,pady=10)
pasword_entry=Entry(newWindow,textvariable=password_text,width=20,state=DISABLED).grid(row=3,column=2)
Button(newWindow,text="Show",command=Show,fg="#00FF00",bg="black",pady=10).grid(row=4,column=1)
I saw many YT vids . ListBox was working globally but in my its not working globally
EDIT: after giving parenthesis to ListBox() New error arises
Traceback (most recent call last):
File "C:\Program Files\Python38\lib\tkinter\__init__.py", line 1895, in __call__
return self.func(*args)
File "d:/Python files/cybersecurity/password manager/password_test.py", line 24, in Show
Selected=lbox.get(lbox.curselection())
File "C:\Program Files\Python38\l`enter code here`ib\tkinter\__init__.py", line 3190, in get
return self.tk.call(self._w, 'get', first)
_tkinter.TclError: bad listbox index "": must be active, anchor, end, #x,y, or a number
The error message simply means that the method was not invoked on the object but on the class instead. In the first code snippet, you didn't seem to instantiate a ListBox object.
You must change the line
lbox = Listbox
to something like:
# Tkinter window object
window = Tk()
# Create ListBox object and bind to the Tkinter window
lbox = Listbox(window)
In the above snippet, an instance of ListBox is created on which the method curselection() could be called. Give more emphasis to the argument passed to ListBox. The window variable used above is an instance of the Tk class which essentially constructs the Tkinter window. Without this argument, the listbox widget won't know which window it must bind to.
When I try to run my code I get an error saying that:
Traceback (most recent call last):
File "C:/Users/Vilho/PycharmProjects/BitlifeYritys1.0/main.py", line 37, in <module>
kill = Button(screen1, text="End game", bg="green", command=end_game("end game button was pressed"), height=4, width=11)
File "C:/Users/Vilho/PycharmProjects/BitlifeYritys1.0/main.py", line 9, in end_game
main_screen.destroy()
NameError: name 'main_screen' is not defined
I don't know what caused the error because I tried to put globals everywhere I could.
The rest of the code is here:
https://shrib.com/?v=nc#VioletCrestedTuraco4wYoed9
You don't define main_screen until you call main_game:
def main_game():
global main_screen
main_screen = Tk()
But you never call this function.
You do, however, call the end_game function. This means that you are calling the destroy method on an object that does not yet exist:
main_screen.destroy()
Conclusion: you either need make sure that main_game is called before end_game, or you need to create a blank window (which might not be the best idea).
I have an application that has a entry field and a button:
from subprocess import *
from Tkinter import *
def remoteFunc(hostname):
command = 'mstsc -v {}'.format(hostname)
runCommand = call(command, shell = True)
return
app = Tk()
app.title('My App')
app.geometry('200x50+200+50')
remoteEntry = Entry(app)
remoteEntry.grid()
remoteCommand = lambda x: remoteFunc(remoteEntry.get()) #First Option
remoteCommand = lambda: remoteFunc(remoteEntry.get()) #Second Option
remoteButton = Button(app, text = 'Remote', command = remoteCommand)
remoteButton.grid()
app.bind('<Return>', remoteCommand)
app.mainloop()
and I want that when I insert an ip/computer name to the entry field it will sent it as a parameter to the command of the button, so when I press Return or pressing the button it will remote the computer with that name/ip.
When i execute this code with the first option (look at the code) it works only I press the Return key, and if I press the button this is the error:
Exception in Tkinter callback
Traceback (most recent call last):
File "/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/lib-tk/Tkinter.py", line 1532, in __call__
return self.func(*args)
TypeError: <lambda>() takes exactly 1 argument (0 given)
If I try the second option of remoteCommand only if I try to press the button It work but I if press the Return key i get this error:
Exception in Tkinter callback
Traceback (most recent call last):
File "/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/lib-tk/Tkinter.py", line 1532, in __call__
return self.func(*args)
TypeError: <lambda>() takes no arguments (1 given)
The only difference between the two is if lambda gets an argument or not.
The best solution in my opinion is to not use lambda. IMO, lambda should be avoided unless it really is the best solution to a problem, such as when a closure needs to be created.
Since you want the same function to be called from a binding on the return key, and from the click of a button, write a function that optionally accepts an event, and then simply ignores it:
For example:
def runRemoteFunc(event=None):
hostname = remoteEntry.get()
remoteFunc(hostname)
...
remoteButton = Button(..., command = remoteFunc)
...
app.bind('<Return>', remoteCommand)
Commands do not get arguments. Event handlers get an event as an argument. To have a function serve as both, use a default argument.
def remote(event=None):
remoteFunc(remoteEntry.get())
I am trying to put together a GUI that would read from a continuously updated TXT file and updated every once in a while. So far I succeeded with the first part and I am failing to use 'root.after()' to loop the whole thing but it results in NameError:
import tkinter as tk
root = tk.Tk()
class App:
def __init__(self, root):
frame = tk.Frame(root)
frame.pack()
iAutoInEN = 0
iAvailableEN = 0
self.tkAutoInEN = tk.StringVar()
self.tkAutoInEN.set(iAutoInEN)
self.tbAutoInEN = tk.Label(root, textvariable=self.tkAutoInEN)
self.tbAutoInEN.pack(side=tk.LEFT)
self.button = tk.Button(frame, text="Start", fg="red",
command=self.get_text)
self.button.pack(side=tk.LEFT)
def get_text(self):
fText = open("report.txt") #open a text file in the same folder
sContents = fText.read() #read the contents
fText.close()
# omitted working code that parses the text to lines and lines
# to items and marks them with numbers based on which they are
# allocated to a variable
if iLineCounter == 1 and iItemCounter == 3:
iAutoInEN = int(sItem)
self.tkAutoInEN.set(iAutoInEN)
root.after(1000,root,get_text(self))
app = App(root)
root.mainloop()
try:
root.destroy() # optional; see description below
except:
pass
The first instance runs without any problems and updates the value from 0 to the number in the TXT file but is accompanied with an error
Exception in Tkinter callback
Traceback (most recent call last):
File "C:\...\Python35\lib\tkinter\__init__.py", line 1549, in __call__
return self.func(*args)
File "C:/.../pythonlab/GUI3.py", line 117, in get_text
self.after(1000,root,get_text())
NameError: name 'get_text' is not defined
EDIT:
When changed to the recommended "self.after(1000,self.get_text)"
class App:
...
def get_text(self):
fText = open("report.txt") #open a text file in the same folder
sContents = fText.read() #read the contents
fText.close()
# omitted code
if iLineCounter == 1 and iItemCounter == 3:
iAutoInEN = int(sItem)
self.tkAutoInEN.set(iAutoInEN)
self.after(1000,self.get_text)
Error changes
Traceback (most recent call last):
File "C:/.../pythonlab/GUI3.py", line 6, in <module>
class App:
File "C:/.../pythonlab/GUI3.py", line 117, in App
self.after(1000, self.get_text)
NameError: name 'self' is not defined
Also please consider this is my very first programme (not only) in Python, so I would appreciate if you are a little bit more explicit with your answers (e.g. when pointing out an indentation error, please refer to an exact line of code).
Because get_text is a method of App class you should call it as self.get_text.
After is a tkinter method. In that case you should call it as root.after. And self refers to the class you are in. So because get_text is a method of current class you should call is with self which is like this in other programming languages like Java.
...
root.after(1000, self.get_text)
...
Firstly, like James commented, you should fix your indentation so that the functions are a part of the class.
Then, change this line
root.after(1000,root,get_text(self))
to this
root.after(1000, self.get_text)
Check out the answer to the following question, which uses the code I just gave you:
Tkinter, executing functions over time