Integrating a control-filter on a project manager with a "new project" button

This is a tiny little grace-note kinda thing, since what I have is completely functional, just not what I want!

I have a project management doc that allows you to manage multiple projects, but I want the user interface to be such that you only see a single project at a time. Easy, select-box and filter(). But I also want there to be a “new project” button. Easy, button and add row() to the project table.

Now the bit I can’t figure out. IF the user clicks “new project,” then the one project they should see should be the new project, right? But for the life of me, I can’t make it happen. I have put my select-box in a table so I can write to it, but I can’t get the button action to both create a new project AND write into the select box (and thus the filter). I am pretty sure the issue is that there are (perfectly natural) delays between the time the button actions complete (from the button’s point of view, as it were) and the time it takes to actually create the new row.

Any suggestions?

I have been trying something like this. But there is no pause with the pop-up table - it appears and immediately disappears.