Object-oriented Software in Ada 95

344 TUI the implementation
procedure Create( The:in out Window;
Abs_X_Crd, Abs_Y_Crd: Positive;
Max_X_Crd, Max_Y_Crd: Positive ) is
begin
if Max_X_Crd < 3 or else Max_X_Crd > Window_Max_X or else
Max_Y_Crd < 3 or else Max_Y_Crd > Window_Max_Y or else
Abs_X_Crd + Max_X_Crd - 1 > Vdt_Max_X or else
Abs_Y_Crd + Max_Y_Crd - 1 > Vdt_Max_Y then
Window_Fatal("Creation window parameter error");
end if;
declare
Top_Bottom: String(1..Max_X_Crd) := (others => '-');
Spaces : String(2 .. Max_X_Crd-1) := (others => ' ');
begin
Top_Bottom(1) := '+'; Top_Bottom(Max_X_Crd) := '+';
The.Max_X := Max_X_Crd - 2; --For border
The.Max_Y := Max_Y_Crd - 2; --For border
The.Abs_Y := Abs_Y_Crd; --Abs position screen
The.Abs_X := Abs_X_Crd; --
The.Pane(1)(1..Max_X_Crd) := Top_Bottom; --Clear / set up
for Y in 2 .. Max_Y_Crd-1 loop
The.Pane(Y)(1..Max_X_Crd):= '|'&Spaces&'|';
end loop;
The.Pane(Max_Y_Crd)(1..Max_X_Crd) := Top_Bottom;
Position( The, 1, 1 );
end;
end Create;
--Top left hand corner
The user callable procedure framework defines the position of the window on the screen. This procedure
uses create to do most of the initialization of the window.
procedure Framework( The:in out Window;
Abs_X_Crd, Abs_Y_Crd: Positive;
Max_X_Crd, Max_Y_Crd: Positive;
Cb:in P_Cbf := null ) is
begin
Create( The, Abs_X_Crd, Abs_Y_Crd, Max_X_Crd, Max_Y_Crd );
Make_Window( The, Visible );
if Cb /= null then
Set_Call_Back( The, Cb );
Register( The'Unchecked_Access, C_Switch );
else
Register( The'Unchecked_Access, C_No_Char );
end if;
end Framework;
The call-back function is set by set_call_back and is called via call_call_back.
procedure Set_Call_Back( The:in out Window; Cb:in P_Cbf ) is
begin
The.Call_Back := Cb;
end Set_Call_Back;
function Call_Call_Back( The:in Window;
Str:in String ) return String is
begin
if The.Call_Back /= null then
return The.Call_Back(Str);
end if;
return "No call back function";
end;
Note:
The value returned by the call-back function is a string.
© M A Smith - May not be reproduced without permission