Showing FMX or VCL Form Created with Delphi in Inno Setup through DLL?

Question

I am trying to show a FMX form in Inno Setup using an dll. i created a DLL and added the form to the DLL.dll. here is the code from the dll:

library DLL;

uses
  System.SysUtils,
  System.Classes,
  Winapi.Windows, Winapi.Messages, System.Variants,
  DLLForm in 'DLLForm.pas' {Form2};

{$R *.res}
procedure ShowForm; stdcall;
begin
  Form2:=TForm2.Create(nil);
  Form2.ShowModal;
  Form2.Free; //Added this line.
  end;

Exports ShowForm;
end.

and here it is the code for inno:

[Setup]
AppName=Windows
AppPublisher=Stack
AppVersion=1.0.0.0
DefaultDirName={pf}\FMXForm

[Files]
Source: Include\DLL.dll; DestDir: {tmp} Flags: dontcopy;

[code]
procedure Show;
external 'ShowForm@Files:DLL.dll stdcall delayload';

procedure InitializeWizard();
begin
  Show;
end;

Setup Compiles but did not showing the form and exits without showing any errors.

It is working fine with cmd,vcl apps but with inno it is not. I used following code to show the form from dll in cmd,vcl apps :

procedure ShowForm; stdcall; external 'DLL.dll';
...
procedure TForm1.FormCreate(Sender: TObject);
begin
Form1.Free;
ShowForm;
end;

Answer 1

You shouldn't really try to call an external Form from within Inno Setup unless absolutely necessary. Inno is a very powerful setup tool that allows you to create custom Pages (Forms) using it's own script. I really encourage you to read very thoroughly Inno's help about custom pages, the process is very well documented. Having said that, here's a piece of code that might get you started:

[Code]

var
  UserInfoPage: TWizardPage;

procedure CreateCustomUserInfoPage;
begin
  UserInfoPage := CreateCustomPage(wpWelcome, 'User information', 'Please insert user information.');

  { First Name Field }

  FNLabel := TLabel.Create(UserInfoPage);
  with FNLabel do
  begin
    Caption := 'First Name:';
    Parent := UserInfoPage.Surface;
  end;

  FNEdit := TEdit.Create(UserInfoPage);
  with FNEdit do
  begin
    Top := FNLabel.Top + FNLabel.Height + 4;
    Width := (UserInfoPage.SurfaceWidth div 2) - 8;
    Parent := UserInfoPage.Surface;
    OnKeyPress := @FNEditOnKeyPress; // Just an event handler. If assigned, it should be implemented in the [code] section.
  end;

  { ...The rest of the fileds here... }

end;

procedure InitializeWizard;
begin
  CreateCustomUserInfoPage;
end;

You declare a global variable of type TWizardPage, implement a procedure of your own to render the form (like: CreateCustomUserInfoPage), inside this procedure you assign the value returned by the built-in function CreateCustomPage to the TWizardPage global variable, add some components to the form, and later on you call this procedure from within the InitializeWizard built-in proc.

This is just a small practical example, it gets more complex depending on what your needs are. But the software's help should cover pretty much anything. As for the DLLs, I only leave those for really intricate work that is not covered by the Inno Setup Pascal Scripting functionality. Hope it helped.