How to self invoke the tkinter button?-CodePudding

I m new to GUI and Tkinter.

I m trying to invoke a function or script without pressing a button from the GUI. It should run the function as soon as the GUI opens.

def example_fun():
    print("this does something...")

img0 = PhotoImage(file = f"img0.png")
b0 = Button(
    image = img0,
    borderwidth = 0,
    highlightthickness = 0,
    command = example_fun,
    relief = "flat")

What is the best way to run the script as soon as GUI opens?

CodePudding user response：

You can run (also referred to as call) the function once when the code first runs by simply calling the function in the main body. Something like

example_fun()
b0 = Button(
    master = root,
    image = img0,
    borderwidth = 0,
    highlightthickness = 0,
    command = example_fun,
    relief = "flat")

will call your function once, while also assigning the same function to your button. Note you were missing the parent argument in your Button, I added it in for you.

CodePudding user response：

The main Python term usually describes the part of code where there is no identation because that is the main scope. In this code example_fun() at the end of your code with no identation to get that running. But this code won't pass the interpreter because main() in that function is calling a function main that is not defined here.