Action button to close a current tab

I am having a action button
I need to close the current browser tab when i click the action button
Is this possible ??

What do you mean with browser tab?

It means ,When i click the action button , i need to close the appsheet application in the Chrome , when i am using in web .and
I need to launch a external URL like
Is this possible ?

Not that I know of.

Not possible.