OnClick to run code.
Creation
SetIcon
nil to remove.
OnClick
cb() when the button is clicked.
() -> ()
Unsubscribe function.
RequireConfirm
"Confirm?", default timeout is 2.5 seconds.
ClearConfirm
Click
Also has everything from ElementHandle: labels, visibility, tooltips, and Destroy. There is no
GetValue / OnChange on a button.