Error: Forward declaration not solved "Info(AnsiString);"

[Wladimir Kowtun]

Hello world!

While practicing to run a procedure from another unit I got this error:

Compilar proyecto, Objetivo: ValeryTweaks.exe: Código de salida 1, Errores: 1, Sugerencias: 1
ufrmmenu.pas(29,15) Error: Forward declaration not solved "Info(AnsiString);"
ufrmmenu.pas(9,15) Hint: Unit "uToolbox" not used in uFRMmenu

I create a unit named: "uToolbox"

and there in the "implementation" I wrote this complex procedure:

Code: Pascal  [Select][+][-]

1. Procedure Info(Mensaje : String);
2. begin
3.      ShowMessage(Mensaje);
4. end;
5.  

In the Form(Unit) named: uFRMmenu where I want to invoke it I:

• Include the uToolbox unit identifier in the uses clause
• Add the procedure header in the "interface > type" section of the Form(Unit) whose invoke the procedure

Then in the clic event of a button in the form that invokes call the procedure like this:

Code: Pascal  [Select][+][-]

1. Info('Mensaje de procedimiento de otra unidad');
2.  

And I got the error message showed above

When the error is generated the ide stops the compilation in the line of the interface> type section where I include the header of the procedure that I tried to invoke:

Code: Pascal  [Select][+][-]

1. interface
2.  
3. uses
4.     uFRMdatabase, Classes, SysUtils, Forms, Controls, Graphics, Dialogs, Menus, ExtCtrls,
5.     StdCtrls, uToolbox;
6.  
7. type
8.  
9.   { TFRMmenu }
10.  
11.   TFRMmenu = class(TForm)
12.     btnTestAnything: TButton;
13.     MainMenu: TMainMenu;
14.     MenuItem1: TMenuItem;
15.     MNUutilidades: TMenuItem;
16.     MNUconexion: TMenuItem;
17.     MNUsalir: TMenuItem;
18.     TimerTransparencia: TTimer;
19.     procedure btnTestAnythingClick(Sender: TObject);
20.     procedure FormCreate(Sender: TObject);
21.     procedure MNUconexionClick(Sender: TObject);
22.     procedure MNUsalirClick(Sender: TObject);
23.     procedure TimerTransparenciaTimer(Sender: TObject);
24.  
25.     Procedure Info(Mensaje : String); // <<<<<< HERE THE COMPILATION CRASHES
26.  

I leave the complete code of the two units:

Code: Pascal  [Select][+][-]

1. unit uToolbox;
2.  
3. {$mode objfpc}{$H+}
4.  
5. interface
6.  
7. uses
8.   Forms, Dialogs, LCLType, Classes, SysUtils;
9.  
10. implementation
11.  
12. Procedure Info(Mensaje : String);
13. begin
14.      ShowMessage(Mensaje);
15. end;
16.  
17. //Procedure Info(Mensaje, Titulo : PChar);
18. //begin
19. //     Application.MessageBox(Mensaje, Titulo, MB_ICONINFORMATION + MB_OK);
20. //end;
21.  
22.  
23. end.
24.  

Code: Pascal  [Select][+][-]

1. unit uFRMmenu;
2.  
3. {$mode objfpc}{$H+}
4.  
5. interface
6.  
7. uses
8.     uFRMdatabase, Classes, SysUtils, Forms, Controls, Graphics, Dialogs, Menus, ExtCtrls,
9.     StdCtrls, uToolbox;
10.  
11. type
12.  
13.   { TFRMmenu }
14.  
15.   TFRMmenu = class(TForm)
16.     btnTestAnything: TButton;
17.     MainMenu: TMainMenu;
18.     MenuItem1: TMenuItem;
19.     MNUutilidades: TMenuItem;
20.     MNUconexion: TMenuItem;
21.     MNUsalir: TMenuItem;
22.     TimerTransparencia: TTimer;
23.     procedure btnTestAnythingClick(Sender: TObject);
24.     procedure FormCreate(Sender: TObject);
25.     procedure MNUconexionClick(Sender: TObject);
26.     procedure MNUsalirClick(Sender: TObject);
27.     procedure TimerTransparenciaTimer(Sender: TObject);
28.  
29.     Procedure Info(Mensaje : String); // <<<<<< HERE THE COMPILATION CRASHES
30.  
31.     //Procedure Info(Mensaje, Titulo : PChar);
32.  
33.   private
34.  
35.   public
36.  
37.   end;
38.  
39. var
40.   FRMmenu: TFRMmenu;
41.  
42. implementation
43.  
44. {$R *.lfm}
45.  
46. { TFRMmenu }
47.  
48. procedure TFRMmenu.TimerTransparenciaTimer(Sender: TObject);
49. begin
50.   if FRMmenu.AlphaBlendValue < 255 then
51.     begin
52.          FRMmenu.AlphaBlendValue:= FRMmenu.AlphaBlendValue + 3;
53.     end
54.   Else
55.     begin
56.          TimerTransparencia.Enabled:=False;
57.     end
58. end;
59.  
60. procedure TFRMmenu.MNUsalirClick(Sender: TObject);
61. begin
62.   Application.Terminate;
63. end;
64.  
65. procedure TFRMmenu.MNUconexionClick(Sender: TObject);
66. begin
67.   frmDatabase.ShowModal;
68. end;
69.  
70. procedure TFRMmenu.btnTestAnythingClick(Sender: TObject);
71. begin
72.      Info('Mensaje de procedimiento de otra unidad');
73.  
74.      //Info('Mensaje del dialogo', 'Titulo del dialogo');
75. end;
76.  
77. procedure TFRMmenu.FormCreate(Sender: TObject);
78. begin
79.   If Not FileExists(ExtractFileDir(ParamStr(0)) + '\Config.ini') then ShowMessage('El archivo de configuracion no existe!')
80.   else ShowMessage('El archivo de configurcion Config.ini se encuentra en el mismo directorio del ejecutable de la aplicacion.');
81. end;
82.  
83. end.
84.  

I really appreciate any guidance, I really have no idea. 

[Bart]

Just remove line 24: Procedure Info(Mensaje : String); // <<<<<< HERE THE COMPILATION CRASHES

Bart

[lucamar]

Yes, remove it from the interface of uFRMmenu and put it on the interface of uToolBox.

The "interface" declaration must be in the same unit where the function is implemented, otherwise the compiler protests that in the unit where you're actually declaring it (uFRMmenu) there is no actual implementation for it, as you have discovered

[Wladimir Kowtun]

Wow thanks for answering so quickly.

I comment on the line you indicated, and now the following error is generated:

Compilar proyecto, Objetivo: ValeryTweaks.exe: Código de salida 1, Errores: 1
ufrmmenu.pas(72,6) Error: Identifier not found "Info"

In the line where I call the procedure in the event click of the button of the FRMmenu form:

Code: Pascal  [Select][+][-]

1. Info('Mensaje de procedimiento de otra unidad');  
2.  

 

[Wladimir Kowtun]

Wow thanks for answering so quickly.

I comment on the line you indicated, and now the following error is generated:

Compilar proyecto, Objetivo: ValeryTweaks.exe: Código de salida 1, Errores: 1
ufrmmenu.pas(72,6) Error: Identifier not found "Info"

In the line where I call the procedure in the event click of the button of the FRMmenu form:

Code: Pascal  [Select][+][-]

1. Info('Mensaje de procedimiento de otra unidad');  
2.  

 

Yes!! That was my mistake. I put the declaration in the right place and it executes well.

Thank you for giving me the most precious thing a man has: his time. Really thank you both.