I am running a script with tkinter that captures user input and then opens a second and possibly a third window based on the input. The issue I am having is capturing user input from the third and final window. Each window is divided up into it's own python class on execution.
Here is the code that calls the third window, which executes properly:
test_assign = TestAssign(mylist)
Here is the third window code:
class TestAssign:
def __init__(self, mylist):
self.mylist = mylist
self.selected_values = []
self.master = Tk()
for i in range(len(mylist)):
setattr(self, 'item'+mylist[i], IntVar())
ch = Checkbutton(master, text='item'+mylist[i], variable=getattr(self, 'item'+mylist[i])
ch.pack()
b = Button(master, text='Next', command=self.get_selected_values)
b.pack()
mainloop()
def get_selected_values(self):
for i in range(len(self.mylist)):
if getattr(self, 'item'+self.mylist[i]) == 1:
self.selected_values.append(self.mylist[i])
self.master.destroy()
Control then returns to the call point (at least I believe it does). Where I attempt to print the selected values:
test_assign = TestAssign(mylist)
while not test_assign.selected_values:
pass
print test_assign.selected_values
Everytime execution gets to the print statement it prints an empty list whether there are boxes checked or not. If I call dir(test_assign) for testing purposes, the checkbox attrs are there. Not sure why I am not able to capture it like this.
Can anyone see the flaw in my code?
Two things:
1)
ch = Checkbutton(master, text='item'+mylist[i], variable=getattr(self, 'item'+mylist[i])
and
b = Button(master, text='Next', command=self.get_selected_values)
I think master should be self.master (but honestly, that almost certainly just a copy/pasting error.)
2) The important one:
if getattr(self, 'item'+self.mylist[i]) == 1:
should be
if getattr(self, 'item'+self.mylist[i]).get() == 1:
(you need to call get on your IntVars to read the value.)
Related
I want to add another widget, in this case a scale widget, to a menu widget in tkinter.
Right now the only solutions I see are creating a new command and open a new window with the scale widget or creating the scale widget elsewhere. Both don't seem too appealing to me.
Any ideas how to archive this are welcome :)
You cant add a scrollbar to it, but I have coded something similar to this. Its a hacky way and maybe its hard to understand but I can try to explain.
Note as Bryan mentioned in the linked Thread, this seems to be a a Windows only solution.
import tkinter as tk
def my_first_function():
print('first')
def my_second_function():
print('second')
def check_for_scroll(event):
check = root.call(event.widget, "index","active")
if check == 0: #index of button up
scroll_up()
root.after(100,lambda e=event:check_for_scroll(e)) # check again after 100ms
if check == file_menu.index('end'):
scroll_down()
root.after(100,lambda e=event:check_for_scroll(e))
def scroll_up():
index_of_first_command=1
index_of_last_command=1
label_of_last_command = file_menu.entrycget(index_of_first_command, 'label')
try:
for i, k in enumerate(dict_of_commands):
if k == label_of_last_command:
previous_command_label = list(dict_of_commands)[i-1]
previous_command = list(dict_of_commands.values())[i-1]
if i != 0: #avoid to get the last as first
file_menu.delete(index_of_first_command) #first before pull down button
file_menu.insert_command(index_of_first_command,
label=previous_command_label,
command=previous_command)
except Exception as e:
print(e)
def scroll_down():
index_of_first_command=1
index_of_last_command=1
label_of_last_command = file_menu.entrycget(index_of_last_command, 'label')
try:
for i, k in enumerate(dict_of_commands):
if k == label_of_last_command:
next_command_label = list(dict_of_commands)[i+1]
next_command = list(dict_of_commands.values())[i+1]
file_menu.delete(index_of_first_command) #first after pull up button
file_menu.insert_command(index_of_last_command,
label=next_command_label,
command=next_command)
except:
pass
space = ' '
dict_of_commands = {'first' : my_first_function,
'second': my_second_function}
root = tk.Tk()
menubar = tk.Menu(root)
root.config(menu=menubar)
file_menu = tk.Menu(menubar,tearoff=0)
menubar.add_cascade(label='File', menu=file_menu)
file_menu.bind('<<MenuSelect>>', check_for_scroll)
file_menu.add_command(label=space+u'\u25B2'+space, font=["Arial", 8,'bold'])
file_menu.add_command(label='first', command=my_first_function)
file_menu.add_command(label=space+u'\u25BC'+space, font=["Arial", 8,'bold'])
root.mainloop()
So this code creates your window and a menubar on it as usal:
root = tk.Tk()
menubar = tk.Menu(root)
root.config(menu=menubar)
file_menu = tk.Menu(menubar,tearoff=0)
menubar.add_cascade(label='File', menu=file_menu)
file_menu.add_command(label=space+u'\u25B2'+space, font=["Arial", 8,'bold'])
file_menu.add_command(label='first', command=my_first_function)
file_menu.add_command(label=space+u'\u25BC'+space, font=["Arial", 8,'bold'])
root.mainloop()
Important for you, is this line here:
file_menu.bind('<<MenuSelect>>', check_for_scroll)
This line binds the event MenuSelect and it happens/triggers if your cursor hovers over a command of your menu. To this event I have bound a function called check_for_scroll and it looks like this:
def check_for_scroll(event):
check = root.call(event.widget, "index","active")
if check == 0: #index of button up
scroll_up()
root.after(100,lambda e=event:check_for_scroll(e)) # check again after 100ms
if check == file_menu.index('end'):
scroll_down()
root.after(100,lambda e=event:check_for_scroll(e))
The line below checks for the index of the command that has triggered the event. With this we check if its button of our interest like the first or last, with the arrows.
check = root.call(event.widget, "index","active")
if its the first for example this code here is executed:
if check == 0: #index of button up
scroll_up()
root.after(100,lambda e=event:check_for_scroll(e)) # check again after 100ms
it calls/triggers the function scroll_up and uses then the after method of tkinter to retrigger itself, like a loop. The scroll_up function is build like the scroll_down just in the opposite direction. Lets have a closer look:
def scroll_up():
index_of_first_command=1
index_of_last_command=1
label_of_last_command = file_menu.entrycget(index_of_first_command, 'label')
try:
for i, k in enumerate(dict_of_commands):
if k == label_of_last_command:
previous_command_label = list(dict_of_commands)[i-1]
previous_command = list(dict_of_commands.values())[i-1]
if i != 0: #avoid to get the last as first
file_menu.delete(index_of_first_command) #first before pull down button
file_menu.insert_command(index_of_first_command,
label=previous_command_label,
command=previous_command)
except Exception as e:
print(e)
In this function we need to know the first and the last position of commands, because we want to delete one and insert another on that position/index. To achieve this I had created a dictionary that contains the label and the the function of the command item of tkinter like below. (This could be created dynamically, but lets keep it for another question)
dict_of_commands = {'first' : my_first_function,
'second': my_second_function}
So we iterate over this enumerated/indexed dictionary in our function and check if the k/key/label is our item of interest. If true, we get the previous_command by listing the dictionary keys and get the extract the key before by this line:
next_command_label = list(dict_of_commands)[i+1]
similar to the value of the dictionary with this line:
next_command = list(dict_of_commands.values())[i+1]
After all we can delete one and insert one where we like to with this:
file_menu.delete(index_of_first_command) #first after pull up button
file_menu.insert_command(index_of_last_command,
label=next_command_label,
command=next_command)
I know that this code can improved by a lot but it seems hard enough to understand as it is. So dont judge me please.
I hope this solves your question, even if it isnt in the way you wanted to. But this code avoids you from hardly code a own menubar.
If there are questions left on my answer, let me know.
i am facing a problem. I'm runnig this code.
import tkinter as tk
root = tk.Tk()
def check():
if len(e.get().split("a")) > 1:
print("contains a")
e = tk.Entry(frame1)
e.grid(row=4,column=1,columnspan=2,padx = (10,10), pady=(5,10), sticky="w e")
e.bind("<Key>",check)
when i type "a" to the entry I wont get nothing printed. I'll get the result by tiping a second character. I think that it happens because the function gets executed before the content has actualy changed. I tried to add a timer on the beginning of the function but it does nothing.
I want get the result by entering the first "a". What should I do?
I think that it happens because the function gets executed before the content has actualy changed.
You're right. If you want the callback to be able to see the character you just typed, you should create a StringVar and bind to that instead of binding to a "<Key>" event on the widget.
import tkinter as tk
frame1 = tk.Tk()
def check(*args):
if "a" in s.get():
print("contains a")
s = tk.StringVar()
e = tk.Entry(frame1, textvariable=s)
s.trace("w", check)
e.grid(row=4,column=1,columnspan=2,padx = (10,10), pady=(5,10), sticky="w e")
frame1.mainloop()
--UPDATE:
I changed
variable=self.optionVal.get()
to
variable=self.optionVal
But nothing changed.Also I wonder why it automatically call self.selected while compiling?
----Original:
I'm trying to get familiar with radiobutton, but I don't think I understand how radiobutton works. Here's a brief code for demonstration:
self.optionVal = StringVar()
for text, val in OPTIONS:
print(text,val)
radioButton = Radiobutton(self,
text=text,
value=val,
variable=self.optionVal.get(),
command = self.selected())
radioButton.pack(anchor=W)
def selected(self):
print("this option is :"+self.optionVal.get())
In my opinion this should work like once I choose certain button, and it prints out "this option is *the value*", however now what it does is once compiled, it prints out everything, and the self.optionVal.get() is blankspace, as if value wasn't set to that variable.
I wonder what happens to my code,
Many thanks in advance.
AHA! I beleive I've figured it out. I had the exact same issue. make sure you are assigning a master to the IntVar like self.rbv=tk.IntVar(master) #or 'root' or whatever you are using):
import Tkinter as tk
import ttk
class My_GUI:
def __init__(self,master):
self.master=master
master.title("TestRadio")
self.rbv=tk.IntVar(master)#<--- HERE! notice I specify 'master'
self.rb1=tk.Radiobutton(master,text="Radio1",variable=self.rbv,value=0,indicatoron=False,command=self.onRadioChange)
self.rb1.pack(side='left')
self.rb2=tk.Radiobutton(master,text="Radio2",variable=self.rbv,value=1,indicatoron=False,command=self.onRadioChange)
self.rb2.pack(side='left')
self.rb3=tk.Radiobutton(master,text="Radio3",variable=self.rbv,value=2,indicatoron=False,command=self.onRadioChange)
self.rb3.pack(side='left')
def onRadioChange(self,event=None):
print self.rbv.get()
root=tk.Tk()
gui=My_GUI(root)
root.mainloop()
try running that, click the different buttons (they are radiobuttons but with indicatoron=False) and you will see it prints correctly changed values!
You're very close. Just take out the .get() from self.optionVal.get(). The Radiobutton constructor is expecting a traced variable, you're giving it the result of evaluating that variable instead.
You need to:
Remove the .get() from the variable=self.optionVal argument in the constructor the button. You want to pass the variable, not the evaluated value of the variable; and
Remove the parenthesis from command=self.selected() and use command=self.selected instead. The parenthesis says "call this function now and use the return value as the callback". Instead, you want to use the function itself as the callback. To better understand this, you need to study closures: a function can return a function (and, if that was the case, that would be used as your callback).
EDIT: A quick reminder, also: Python is not compiled, but interpreted. Your callback is being called while the script is being interpreted.
def view(interface):
choice = interface.v.get()
if choice == 0:
output = "0"
elif choice == 1:
output = "1"
elif choice == 2:
output = "2"
elif choice == 3:
output = "3"
else:
output = "Invalid selection"
return tk.messagebox.showinfo('PythonGuides', f'You Selected {output}.')
class Start:
def __init__(self):
self.root = tk.Tk()
self.root.geometry('500x500')
self.root.resizable(False, False)
self.root.title('find out the degree of severity')
self.v = tk.IntVar()
dolori_ossa = {"nessun dolore": 0,
"dolori articolari": 1,
"frattura composta": 2,
"frattura scomposta": 3}
for (txt, val) in dolori_ossa.items():
tk.Radiobutton(self.root,
text=txt,
variable=self.v,
value=val,
command=lambda:view(self)
).pack()
hey back again with the same code, well edited so it works better. anyway trying to add the button input into the array and that works. what doesn't work is the fact every time i call the function do() the values reset due to them being local. i tried to fix this by making it global(within the class) using the self.store array. this didn't seem to fix the problem so if someone could help would be much appreciated here is the relevant code
def __init__(self,master):#is the master for the button widgets
self.count=0
self.store=["0"]
frame=Frame(master)
frame.pack()
self.addition = Button(frame, text="+", command=self.add)#when clicked sends a call back for a +
self.addition.pack()
self.subtraction = Button(frame, text="-", command=self.sub)#when clicked sends a call back for a -
self.subtraction.pack()
self.equate = Button(frame, text="=", command=self.equate)#when clicked sends a call back for a =
self.equate.pack()
self.one = Button(frame, text="1", command=self.one)#when clicked sends a call back for a -
self.one.pack()
def add(self):
self.do("+")
self.count=self.count+1
def sub(self):
self.do("-")
self.count=self.count+1
def equate(self):
self.do("=")
def one(self):
self.do("1")
self.count=self.count+1
def do(self, X):#will hopefully colaborate all of the inputs
cont, num = True, 0
strstore="3 + 8"#temporarily used to make sure the calculating works
self.store=["2","1","+","2","3","4"]#holds the numbers used to calculate.
for num in range(1):
if X == "=":
cont = False
self.store[self.count]=X
print(self.store[self.count])
print(self.store[:])#test code
if cont == False:
print(self.eval_binary_expr(*(strstore.split())))
self.store=["2","1","+","2","3","4"]
If you initialize it this way in the do function, self.store will be reset to ["2","1","+","2","3","4"] every time you call do(X)
Initialize it outside of the do function if you don't want it to be overwritten.
But if you want to add a value to a list, use append(), extend, or += operator:
self.store+=["2","1","+","2","3","4"]
(if you want it to be done only once, do it in the constructor, __init__ function!)
also,
self.store[self.count]=X
If you try to append to the END of the list self.store, you should just do:
self.store.append(X)
This way, you won't need to count anything, with the risk of forgetting an incrementation and replacing a value by X instead of appending X.
As said above, range(1), it's 0...
Let's do it another way:
def do(self, X):
cont, num = True, 0
liststore=['3', '+', '8']#splitting your string.
#initialize str.store elsewhere!
if X == "=":
cont = False
self.store.append("X")
print(self.store[-1])#getting the last
print(self.store)#the same as self.store[:]
if cont == False:
print(self.eval_binary_expr(*(liststore)))
Simpler, and probably better.
Last thing: in Python, you are usually working with lists (like self.store), not arrays (which come from the module array)
ive tried searching for a solution but couldn't find one that works. I have a 2d list of tkinter Buttons, and i want to change their Text when it is clicked by the mouse. I tried doing this:
def create_board(number):
print(number)
for i in range (0,number):
buttonList.append([])
for j in range(0,number):
print(i,j)
buttonList[i].append(Button(root, text = " ", command = lambda: update_binary_text(i,j)))
buttonList[i][j].pack()
Then when it is clicked it calls this function:
def update_binary_text(first,second):
print(first,second)
buttonList[first][second]["text"] = "1"
When i click a button, it simply does nothing, i had the program display the indexes of the button that was clicked, and they ALL show 4, 4 (this is when the variable number=5) Is there an solution to this?
this is my first python attempt for a class.
Thanks
You can fix this problem by creating a closure for i and j with the creation of each lambda:
command = lambda i=i, j=j: update_binary_text(i, j)
You could also create a callback factory with references to the button objects themselves:
def callback_factory(button):
return lambda: button["text"] = "1"
And then in your initialization code:
for j in range(0, number):
new_button = Button(root, text=" ")
new_button.configure(command=callback_factory(new_button))
new_button.pack()
buttonList.append(new_button)
Whenever I need a collection of similar widgets, I find it's simplest to enclose them in an object and pass a bound-method as callback rather than playing tricks with lambda. So, instead of having a list like buttonList[] with widgets, create an object:
class MyButton(object):
def __init__(self, i, j):
self.i = i
self.j = j
self.button = Button(..., command = self.callback)
def callback(self):
. . .
Now, you have a list buttonList[] of these objects, rather than the widgets themselves. To update the text, either provide a method for that, or else access the member directly: buttonList[i].button.configure(. . .) And when the callback is activated, it has the entire object and whatever attributes you might need in self.