@Phuket2 thanks for your reply and comments.
I had played a little with tkinter befor trying pythonista. There, I made a frame called root and placed all of my widgets in the root.
When I start to think of parent child relationships at different levels, things are starting to make sense.
I will read up on superview.
I am using Pythonista 3
I have made a pyui file with a button and a label.
In my py file I have a defined a function for button action.
I want the function to change the text in the label.
Now I am stuck, what am I missing?
If you think you can help, thank you 😊