How would I go about forgetting a widget that was created by a for loop?
For example, I have this code here:
for getSong in a.findAll('name'):
z += 1
x += 1
if z == 11:
break
else:
text = ''.join(getSong.findAll(text=True))
data = text.strip()
songLab = Label(frame1, text=data)
Afterwards, the user presses a Button and it updates the widget, like so:
def update():
try:
openArtist.pack_forget()
artistLab.pack_forget()
songLab.pack_forget()
getScrobbledTracksArtist()
except NameError:
getScrobbledTracksArtist()
The other widgets get removed by the one created in the for loop does not.
Example here:
Before updating widgets
After updating widgets
As you can see, only one line of the widget was removed.
Edit
I tried doing the duplicate but it is not working for me.
I made a list and made sure the labels were being added to the list, they are.
labels = []
for getSong in a.findAll('name'):
z += 1
x += 1
if z == 11:
break
else:
text = ''.join(getSong.findAll(text=True))
data = text.strip()
songLab = Label(frame1, text=data)
labels.append(songLab)
songLab.pack()
Then after a Button is pressed, the widgets update.
def update1():
try:
openArtist.pack_forget()
artistLab.pack_forget()
labels[0].destroy()
print labels
getScrobbledTracksArtist()
except NameError:
getScrobbledTracksArtist()
The labels are still in the list and are not being destroyed.
Like any other widget, you simply need to keep a reference to it. For example, you could append each widget to a list, then iterate over the list to remove the widgets.
Let's take a look at this code:
def update1():
try:
openArtist.pack_forget()
artistLab.pack_forget()
labels[0].destroy()
print labels
getScrobbledTracksArtist()
except NameError:
getScrobbledTracksArtist()
you are only ever deleting the first label in the list, and then you are failing to remove it from the list. What you need to do instead is to loop over the list, destroying each widget. Then you can reinitialize the list:
for label in labels:
label.destroy()
labels = []
However, you have another problem in that it appears that labels may be a local variable. You will need to declare it as global so that the two different functions will be able to access and modify the list.
None of this is related to tkinter, this is simply how all python objects work.
Related
I'm trying add/remove an item (text of checkbox) to/from a list whenever a checkbox is checked/unchecked in tkinter.
My idea was to add a command to the checkbutton, like:
cb = Checkbutton(master,...,command=some_fun)
but I cannot think of a way to define the function. I was thinking the function should contain the widget attribute cget('text'), but the problem is I have many checkboxes made with the help of a loop.
I guess the question is: how can I reference the checkbox whose state got changed and is therefore calling the function some_fun?
The way I generated the checkboxes is:
cb_identities = []
for i in range(cb_max_num):
cb = Checkbutton(frame_data,bg="white")
cb_identities.append(cb)
And then I'm dynamically changing them depending on some radiobuttons:
def fun_chck(): #shows or hides checkbuttons based on radiobutton input
data = read_data(rb_var.get())
for i in range(cb_max_num):
cbname = (cb_identities[i])
if len(data)-1 < i:
cbname.grid_forget()
else:
cbname.config(text=data[i]) #I would place some_fun here, which gets text option of checked box
cbname.grid(row=i,column=1,sticky=W)
Update! I managed with the following code for anyone interested:
cb_var_init = [0] * cb_max_num #create the initial list of inactive checkbuttons, all 0
input_params=[] #list which needs to be populated/depopulated based on checkbutton state
def get_data(data): #populates a list with parameter from checked checkbuttons,
global cb_var_init
cb_var_list = list(map(lambda var: var.get(),list(cb_var.values())))
for i in range(len(data)):
if cb_var_list[i] > cb_var_init[i]:
input_params.append(data[i])
elif cb_var_list[i] < cb_var_init[i]:
input_params.remove(data[i])
cb_var_init = cb_var_list
return(input_params)
cb_var is a dictionary of IntVars, and data is a list of checkbuttons' names.
As for the command on each checkbutton, I used cbname.config(text=data[i],command=lambda: get_data(data)) as suggested in another topic for functions with arguments.
Now each time I check a checkbutton, I immediately get a list of parameters which should show in the next Frame, which is dynamically updated.
I have a function, which based on the count generates the comboboxes. I want to destroy any combobox which is available already whenever my count variable changes. I used winfo_exists to do this...but it throws an attribute error every time. Please help me with this.
Here is the code of that function:
def create(event):
count = combo.current()
print ("count")
print(count)
for i in range(1,count+2):
if (create_combo[i].winfo_exists()):
create_combo[i].destroy()
for i in range (1,count+2):
create = tk.StringVar()
create_combo[i]= ttk.Combobox(new_window_2,width = 15,textvariable = create, values = sheets)
#create_combo.set("Sheet " + str(i))
create_combo[i].grid(column = i, row =4, padx=10,pady=10)
To delete the widgets which are created in loop, can be deleted by using the method available in this link
Python Tkinter :removing widgets that were created using a for loop
This worked for me... I dont understand why winfo_exists didn't work.
Anyway Thanks!!
list_of_owner_widgets = []
def create(event):
count = combo.current()
print(count)
for widget in list_of_owner_widgets:
widget.destroy()
for i in range (1,count+2):
create = tk.StringVar()
create_combo[i]= ttk.Combobox(new_window_2,width = 15,textvariable = create, values = sheets)
list_of_owner_widgets.append(create_combo[i])
create_combo[i].grid(column = i, row =4, padx=10,pady=10)
If you wish to destroy a Python widget, be it a Checkbox in your case, you use the following code.
It is a lot easier to remove and show widgets using the .grid method!
Your code:
create_combo[i].destroy()
I assume (as I can see further down the code file) that you used the grid method. In which case I would simply change the code to:
create_combo[i].grid_forget()
Hope This Helps!
From your post:
for i in range(1,count+2):
if (create_combo[i].winfo_exists()):
create_combo[i].destroy()
And the error:
AttributeError: 'str' object has no attribute 'winfo_exists'
I can infer that:Your create_combo must be a list full of string(Instead of Combobox widget).
You could add print(create_combo) before the first for loop to check the value in create_combo.It must be a list full of string.
And it seems that your problem is not here,you should check the way how you create the create_combo.
lets assume create_combo = ['a','b','c']. So I am creating three comboboxes create_combo[0...2]. So name of the comboboxes(widgets) is a, b, c.
No,you couldn't.
If really want to get a list of comboboxes you create,you should use:
create_combo = []
for i in range(3):
t = ttk.Combobox(xxxxx)
t.grid(xxxxxx)
create_combo.append(t) # append it to your create_combo
And then,you could use:
for i in create_combo:
if i.winfo_exists(): # i should be a widget,not string
xxxxxxx # your job
I have a table (grid) I'm creating, constituted of labels.
These labels are showing elements I'm adding to a list, therefore, when I add a new obj to the list, the table will grow, showing more labels.
My intent is that I can click a label and have it print the row of the table that that label is in.
import tkinter as tk
phrasesdb = []
def debug(event):
#this is where I'd have it print the row
#but how do I get it?
#for example, it the label I pressed was in the row 2, it'd print 2
print( ??? )
#Add obj to list
def addline():
##This creates new obj with values from the input fields, and inserts it in the list
newobj = {"text": newtext.get()} #This is getting the text from an Entery
phrasesdb.append(newobj)
##This shows new obj on the table
newesttext = tk.Label(tableframe, text=newobj["text"])
newesttext.grid(row=len(phrasesdb), column=1, sticky=tk.W)
newesttext.bind("<Double-Button-1>", debug)
I'm already able to show them in the table, and to have it recognize I'm pressing the correct label (tested with a simple print("yup, this is it") ), but I'm not being able to figure out how to access the row of the label I'm clicking.
I'm kinda new to python and especially tkinter, so sorry if this is a really easy question, but I'm not finding the answer anywhere else...
You can use the grid_info method which will return a dictionary of the item's grid attributes.
def debug(event):
widget = event.widget
info = widget.grid_info()
row = info['row']
If I understand your problem correctly using .grid_info()['row'] on the label you already received after clicking should return the result you need.
I am beginning GUI in Python 3.5, and I am trying to setup a simple qwerty keyboard. Based on the examples, I tried the following code
from tkinter import Tk, Label, RAISED, Button, Entry
self.window = Tk()
#Keyboard
labels = [['q','w','e','r','t','y','u','i','o','p'],
['a','s','d','f','g','h','j','k','l'],
['z','x','c','v','b','n','m','<']]
n = 10
for r in range(3):
for c in range(n):
n -= 1
label = Label(self.window,
relief=RAISED,
text=labels[r][c])
label.grid(row=r,column=c)
continue
This gives me the first row, but it does not return anything else. I tried simply using 10 as the range, which created the first two rows of the keyboard, but it still did not continue onto the last row.
Your issue is in the line n -= 1. Every time a label is created, you make n one less- after the first whole row, n==0, and thus the range is 0>0, and ranges never include the high bound- for c in range(0) will just drop from the loop (as it has looped through all the nonexistent contents).
A better solution involves iterating through the lists instead of through the indexes- for loops take any iterable (list, dictionary, range, generator, set, &c.);
for lyst in labels:
# lyst is each list in labels
for char in lyst:
# char is the character in that list
label = Label(... text=char) # everything else in the Label() looks good.
label.grid(...) # You could use counters for this or use ennumerate()-ask if you need.
# The continue here was entirely irrelevant.
Is this what you want it to do? Let me know if you need me to explain it further but basically what I'm doing is first filling the columns in each row. So row remains 0 and then as I loop through the column (the inner list) I fill in each of the keys, then on to the next row and etc.
from tkinter import Tk, Label, RAISED, Button, Entry
window = Tk()
#Keyboard
labels = [['q','w','e','r','t','y','u','i','o','p'],
['a','s','d','f','g','h','j','k','l'],
['z','x','c','v','b','n','m','<']]
for r in labels:
for c in r:
label = Label(window, relief=RAISED, text=str(c))
label.grid(row=labels.index(r), column=r.index(c))
window.mainloop()
I have a method that is suppose to take a search parameter and remove everything from the list that does not meet the parameter. But when it runs it removes list items at almost random. I've debugged it and it correctly determines if an item needs to be removed but it doesn't remove the right one. I think it has something to do with when I remove one item it messes up the indexes of the rest of the list, which doesn't with with my method of tracking the index.
I posted the whole class but the relevant code is towards the bottom
class StudentFinderWindow(Tkinter.Toplevel):
def __init__(self):
Tkinter.Toplevel.__init__(self) # Create Window
##### window attributes
self.title('Edit Students') #sets window title
##### puts stuff into the window
# text
editStudentInfoLabel = Tkinter.Label(self,text='Select the student from the list below or search for one in the search box provided')
editStudentInfoLabel.grid(row=0, column=0)
# entry box
self.searchRepositoryEntry = Tkinter.Entry(self)
self.searchRepositoryEntry.grid(row=1, column=0)
# list box
self.searchResults = Tkinter.Listbox(self)
self.searchResults.grid(row=2, column=0)
# search results initial updater
self.getStudentList()
for student in self.studentList:
self.searchResults.insert(Tkinter.END, student)
##### event handler
self.searchRepositoryEntry.bind('<KeyRelease>', self.updateSearch)
This is the relevant code
def updateSearch(self, event):
parameters = self.searchRepositoryEntry.get()
int = 0
currentList = self.searchResults.get(0, Tkinter.END)
length = len(parameters)
print(parameters)
print(length)
for i in currentList:
if not i[0:length] == parameters:
self.searchResults.delete(int)
print(i[0:length] == parameters)
print(i[0:length])
print(int)
int += 1
def getStudentList(self):
global fileDirectory # gets the directory that all the files are in
fileList = listdir(fileDirectory) # makes a list of files from the directory
self.studentList = [] # makes a new list
for file in fileList: # for loop that adds each item from the file list to the student list
self.studentList.append(file[:-4])
When you delete an item, everything below it moves up causing the index of all following items to change. The simplest solution to this sort of a problem (it's also common when deleting words from a text widget) is to delete backwards, starting at the end.
I think you already know the problem. When you delete an item, the index for the rest of the items change. For example, if you delete the 4th item, then the 5th item becomes the "new" 4th item. So you don't want to increment int whenever you delete an item. You can implement that with continue:
for i in currentList:
if not i[0:length] == parameters:
self.searchResults.delete(int)
continue # <-- Use continue so `int` does not increment.
int += 1
PS. It's not good coding style to use int as a variable name -- in Python it masks the built-in function of the same name.