User input in overlay bubble

Here is my requirement:

After clicking add reminder, there is a overlay like the screenshot showing in the page. There are some input fields which need users to input. After clicking Add button, the overlay closes and the input field value will be displayed in the parent page. I can't use Popup_Editor. I just want to have this. It appears after clicking add reminder and it disappears when clicking somewhere else in the page. How can I do that? 

Thanks very much.

Hi Nina,

It seems you want to have something that's not available :). Joking aside, the info balloon is not meant for user input. If you need something like that, you'll need to create it yourself. You can start by cloning RichWidgets and taking a look at how it's implemented.