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tkinter global variable


On Fri, 13 Nov 2020 16:04:03 +0000, Stefan Ram wrote:

> ChalaoAdda <chalao.adda at gmail.com> writes:
>>On Fri, 13 Nov 2020 15:41:20 +0000, Stefan Ram wrote:
>>> ChalaoAdda <chalao.adda at gmail.com> writes:
>>>>I am trying to read a file from askopenfilename outside the function.
>>>>I am getting blank file name. What am I doing wrong? Here is my code.
>>>It is possible that you try to read from "pic" before "on_openfile"
>>>ever was executed.
>>I didn't get you. I click on the menu item "Open" and then from the
>>filedialog select a file. And then outside that function I am trying to
>>read and print the file.
> 
>   I have added two additional statements to your source code:
>   print( "A" ) and print( "B" ).
> 
>   If you now execute this new source code, you might observe that "B" is
>   being printed before "A" is being printed.
> 
> from tkinter import *
> from tkinter import filedialog
> 
> def on_openfile():
>     print( "A" )
>     global pic pic = filedialog.askopenfilename()
> 
> 
> root = Tk()
> 
> menubar = Menu(root)
> root.config(menu=menubar)
> file_menu = Menu(menubar) file_menu.add_command(label="Open",
> command=on_openfile) file_menu.add_command(label="Exit",
> command=root.destroy)
> menubar.add_cascade(label="File", menu=file_menu)
> 
> 
> print( "B" )
> f = open(pic)
> print(f.read())
> 
> root.mainloop()

Ok. I got the point. So what do I need to do access the variable? How do 
I return a value from that function?

Thanks.