Problème Econversion Error lors de l'affichage d'une info bulle dans une f
cs_DarkSky
Messages postés4Date d'inscriptionsamedi 18 janvier 2003StatutMembreDernière intervention 9 février 2003
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4 févr. 2003 à 15:34
Clorish
Messages postés48Date d'inscriptiondimanche 15 juin 2003StatutMembreDernière intervention 6 décembre 2007
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16 juin 2003 à 20:27
Salut a tous,
j'ai créer un projet MDI avec Delphi 6 donc les fenetre MDi Filles sont dans une DLL.
j'ai une erreur EConversionError a la place de l'affichage de l'info bulle Hint dans les composants de ma MDI Fille.
Le problème est visiblement lié avec l'utilisation de TScreen ?
Si quelqu'un a une idée, merci d'avance ......
thx a tous pour ce forum.
Voici le source des différents modules :
-------------------------------------
Voici le code du programme MDI Parent
-------------------------------------
unit MAIN;
// Définition des prototypes pour les fonctions de la DLL
TDLLEntryPoint = procedure(dwReason: DWORD); stdcall;
TCreateMDIChildForm = procedure(App: TApplication; Scr: TScreen);
TDestroyMDIChildForm = procedure;
var
MainForm: TMainForm;
// Déclaration des fonctions exportés par la DLL
LibHandle : THandle;
DLLEntryPoint : TDLLEntryPoint;
CreateMDIChildForm : TCreateMDIChildForm;
DestroyMDIChildForm: TDestroyMDIChildForm;
implementation
{$R *.dfm}
uses about;
procedure TMainForm.FileNew1Execute(Sender: TObject);
begin
CreateMDIChildForm(Application, Screen);
end;
procedure TMainForm.HelpAbout1Execute(Sender: TObject);
begin
AboutBox.ShowModal;
end;
procedure TMainForm.FileExit1Execute(Sender: TObject);
begin
Close;
end;
procedure TMainForm.FormCreate(Sender: TObject);
begin
if LibHandle <> 0 then
begin
ShowMessage('Library already loaded');
Exit;
end;
LibHandle := LoadLibrary('DLL.dll');
try
if LibHandle = 0 then
begin
raise Exception.Create('Unable to load DLL');
Exit;
end;
@DLLEntryPoint := GetProcAddress(LibHandle, 'DLLEntryPoint');
@CreateMDIChildForm := GetProcAddress(LibHandle, 'CreateMDIChildForm');
@DestroyMDIChildForm:= GetProcAddress(LibHandle, 'DestroyMDIChildForm');
except
FreeLibrary(LibHandle);
end;
end;
procedure TMainForm.FormClose(Sender: TObject; var Action: TCloseAction);
begin
@CreateMDIChildForm := nil;
@DestroyMDIChildForm:= nil;
if LibHandle = 0 then
begin
ShowMessage('Library already released');
Exit;
end;
//The two following procedures can be used to detach the dll
//FreeLibrary(LibHandle);
{ or }
DLLEntryPoint(DLL_PROCESS_DETACH); //The procedure call can be used for VB and/or Delphi
LibHandle := 0;
Action := caFree;
end;
end.
------------------------
Voici le code de la DLL
------------------------
library Dll;
uses
SysUtils,
Windows,
Forms,
Classes,
Unit1 in 'Unit1.pas' {Form1};
var
DLLApp: TApplication;
DLLScr: TScreen;
DLLAppHandle: THandle;
{$R *.res}
procedure RestoreAppAndScr;
begin
Screen := DLLScr;
Application := DLLApp;
end;
procedure CreateMDIChildForm(App: TApplication; Scr: TScreen);
begin
// if not Assigned(Form1) then
// begin
Application := App;
//Assign Screen Object
if Assigned(Scr) then Screen := Scr;
//DLLForm2 := TDLLForm2.Create(Application);
Form1 := TForm1.Create(Application.MainForm);
Form1.Caption := 'MDI Child Form';
Form1.Show;
// end
// else
// begin
// Form1.Show;
// end;
end;
procedure DestroyMDIChildForm;
begin
if Assigned(Form1) then
begin
Form1.Free;
end
else
begin
//ShowMessage('Form was already destroyed.');
end;
Form1 := nil;
RestoreAppAndScr;
end;
//DLL Entry Point
//----------------
procedure DLLEntryPoint(dwReason: DWORD); stdcall; //register; //stdcall;
begin
case dwReason of
DLL_PROCESS_ATTACH: //1
begin
DLLAppHandle := Application.Handle;
DLLApp := Application;
DLLScr := Screen;
end;
DLL_PROCESS_DETACH: //3
begin
// Destroy des fenetres
// Rend les handles au programme principal
RestoreAppAndScr;
Application.Handle := DLLAppHandle;
end;
DLL_THREAD_ATTACH : {ShowMessage('Thread Attach')}; //2
DLL_THREAD_DETACH : {ShowMessage('Thread Detach')}; //0
end;
end;
exports
DLLEntryPoint, // Point d'entrée de la DLL
CreateMDIChildForm, // Création de la fenetre MDI
DestroyMDIChildForm; // Destruction de la fenetre MDI
begin
//DLLEntryPoint is specifically a Win32 and C++ implementation
//DLLProc is a pointer variable from the SYSTEM Unit (automatically included)
//The SYSTEM Unit is responsible for executing code assinged to DLLEntryPoint
DLLProc := @DLLEntryPoint; //Assign the address of DLLEntryPoint to DLLProc
DLLEntryPoint(DLL_PROCESS_ATTACH); //Indicate that the DLL is attaching to the process
end.
//In VB Call this to detach the DLL before the main process terminates
//DLLEntryPoint(DLL_PROCESS_ATTACH);
-------------------------------------------------
Voici le code de la fenetre MDI Fille Dans la DLL
-------------------------------------------------
unit Unit1;
type
TForm1 = class(TForm)
Edit1: TEdit;
procedure FormDestroy(Sender: TObject);
procedure FormClose(Sender: TObject; var Action: TCloseAction);
private
{ Déclarations privées }
public
{ Déclarations publiques }
end;
var
Form1: TForm1;
implementation
{$R *.dfm}
procedure TForm1.FormDestroy(Sender: TObject);
begin
Form1 := nil;
end;
procedure TForm1.FormClose(Sender: TObject; var Action: TCloseAction);
begin
//if Action := caFree; then you should nil the form variable
Action := caFree;
end;
