I'm making the web-UI for my software more accessible by improving the usage of ARIA. In various places, I have multiple pop-up windows that get opened by a button. See the image below for an example. This window is shown when the 'Delete' button is pressed and is closed using the cross in the top right or the 'Cancel' button.
How do I make it clear to ARIA that a specific button shows a window-blocking section? It looks like the dialog role is appropriate? It seems to me like I should supply the ID of the window to the button so that ARIA knows which section is shown when I click the button. But I can't find any descriptor for that. How does ARIA know which element is the window, to which the focus should be given?
EDIT: And how do I tell ARIA that when you click the cross or 'Cancel' button, that the window closes and focus is put back to the 'main' window?