hi.there am Gao from( south africa) just need some help with creating a function . am tryng to enabl

hi.there am Gao from( south africa)
just need some help with creating a function .
am tryng to enable buttons from xaml in c# xamarin studio meaning,
1. i have a login form and menu form both contain buttons.
and menu buttons are disabled from xaml.thus i wan to enable those buttons when the login button is clicked from the login form. so i dont know how to create its function.since am new in xamarin studio. any one
please. what i have tried so far : public bool frmenabled(bool enabled)
{
if (enabled)
{
sales.isenabled=true;
}
reutrn true;
}