How to generate new APP components while a MATLAB APP is running?

I want to design a MATLAB APP to plot polygonal simply/multiply connected domain whose boundary vertices can be given by users. Here is an example of polygonal multiply connected domain, i.e. the gray area.

However, I can't find an existing APP component that can enable users to add boundaries and their vertices dynamically while the APP is running,

i.e..

How can I realize this function in my APP?

[Rik]

You need to implement a function that creates a new pair of text boxes and moves the plus button. I'm not aware of anything that already does what you want, but creating new components should not be hard. What have you tried so far?

[jiahao tian]

Oh, thank you very much! It's indeed a simple question, but I didn't know it in the past.