Object-oriented Software in Ada 95

352 TUI the implementation
23.8.1 Implementation of the class Menu
The implementation of the class is:
with Pack_Constants;
use Pack_Constants;
package body Class_Menu is
The procedure Set_Up populates the displayed menu window with the names of the menu items.
procedure Set_Up( The:in out Menu;
Active:in Positive ) is
Me: Menu_Item;
begin
Create( The, 1, 1, (1+Max_Menu)*Active+1, 3 );
for I in 1 .. Active loop --Display menu names
Get_Menu_Name( The, I, Me );
Put( The, Me ); Put( The, "|" );
null;
end loop;
Menu_Spot( The, C_Cursor ); --Mark current
end Set_Up;
In the procedure Framework the class type is described as Menu'Class. This is so that a run-time dispatch
will be performed on inherited procedures or functions in any class derived from this class.
procedure Framework( The:in out Menu'Class;
M1:in String:=""; W1:in P_Menu:=null; Cb1:in P_Cbf:=null;
M2:in String:=""; W2:in P_Menu:=null; Cb2:in P_Cbf:=null;
M3:in String:=""; W3:in P_Menu:=null; Cb3:in P_Cbf:=null;
M4:in String:=""; W4:in P_Menu:=null; Cb4:in P_Cbf:=null;
M5:in String:=""; W5:in P_Menu:=null; Cb5:in P_Cbf:=null;
M6:in String:=""; W6:in P_Menu:=null; Cb6:in P_Cbf:=null
) is
Spaces : Menu_Item := ( others => ' ' );
Active : Menus_Index := 1;
procedure Set_Up( Mi:in String; Wi:in P_Menu;
Cb:in P_Cbf; N:in Menus_Index ) is
begin
if Mi /= "" then Active := N; end if; --A menu item
The.Menu_Set( N ) :=
(" "&Mi&Spaces(1 .. Max_Menu-1-Mi'Length), Wi, Cb);
end Set_Up;
begin
Set_Up( M1, W1, Cb1, 1 ); Set_Up( M2, W2, Cb2, 2 );
Set_Up( M3, W3, Cb3, 3 ); Set_Up( M4, W4, Cb4, 4 );
Set_Up( M5, W5, Cb5, 5 ); Set_Up( M6, W6, Cb6, 6 );
The.Number := Active;
Set_Up( The, Positive(Active) );
end Framework;
Note: The procedure set_up which is called from within framework constructs the internal
representation for the window.
The procedure menu_spot highlights the menu item selected.
© M A Smith - May not be reproduced without permission