java, xml - Pop up menu in app to appear and add Layout dynamically

I've been googling this sort of stuff for several days now and found a couple pages that did say that it works, but it sorta doesn't explain the process and stuff.

http://ift.tt/1SqMgfe http://ift.tt/1I9MTSy

Other than these two, I wanted to know what it wanted me to do on the MainActivity.java to get this working.

I've already got the button on my menu_main.xml, but am I missing something to make it work? Does the method have to be in the MainActivity.java then call the method in the other java class to make it work? Or does the MainActivity.java have to just instantiate the other java class and the button can easily call the method in the other class?

Lastly, I'm making an app that will start off with an empty background with a text, implying that it is empty and there is nothing here. There is a button on the top right that you hit that will create a LinearLayout and after adding in information on the pop up menu on the earlier issue, you then add the LinearLayout onto the page and erase the text. I can easily erase the text but adding the LinearLayout is proving to be difficult. I couldn't find a proper answer for this one.

Image sample of how it will look initially:

What will happen after hitting the top right button and filling in info on pop up (ignore missing add and settings button):

Thank you for your help.