[Tutor] FW: NameError: name 'pics' is not defined

[Alan Gauld]

On 15/04/2021 19:49, derek wrote:

>  from tkinter import filedialog
> 
>  global pics

This does not do what you think it does.
In fact at this point in the code I don't think
it does anything! Certainly nothing useful.

global is used inside a function to resolve name
conflicts. To tell Python that a given name should
refer to the global(ie module) scope and not be
created as a local variable inside the function.

It does not create the variable.

>  # definitions
>  def openFile():
>      pics = filedialog.askopenfilename()

And this pics is local to the function because
you did not declare it global inside the function.
You need to move the global line inside this function.

>  win = tk.Tk()
>  button = Button(text=TitleOfOFD, command=openFile)

You need to tell the Button who its parent is otherwise
it will be an orphan control. ie you need win as the first
argument.

>  canvas = Canvas(win, width=300, height=300)
>  canvas.create_image(200, 200, anchor=NW, image=pics)

And here you refer to a non existent pics. So presumably,
this is where the error comes from.

When posting always include the full error trace,
it contains a lot of useful details


-- 
Alan G
Author of the Learn to Program web site
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