popupMenuF :: (Graphic b, Eq b) => [(a, b)] -> F c d -> F (Either [(a, b)] c) (Either a d)
popupMenuF alts fudget
popupMenuF
provides a popup menu. The menu is normally hidden, but pops up when
the a specific mouse button is pressed over the fudget to which the popup
menu is attached, so that an item can be picked from the
menu. The menu is removed as soon as the mouse button is released.
Left alts
causes the current menu to be replaced by a new
list of alternatives alts
.
Right y
causes y
to be passed to the argument fudget.
Left x
is output if menu item x
is selected.
Right y
is output if the argument fudget outputs y
.
alts :: [(a, b)]
fudget :: F c d
Left x
input
may change.