[Lazarus] RE : Embedding a standard dialogue

[Mark Morgan Lloyd]

Ludo Brands wrote:
>> OK, If I can lead on from this. The cause of bug 21792 that I raised 
>> yesterday is, I'm told, that I'd set the main form visible but 
>> minimised. The reason I'd done this is that before the form was 
>> displayed I wanted the user to provide database login credentials, I 
>> couldn't rely on a standard dialogue for that since I also needed to 
>> have him select what kind of database- PostgreSQL or Firefox- 
>> as well as 
>> the server and possibly port.
>>
>> What is the correct thing to do in this sort of situation? 
>> I've seen a 
>> description of a hack for Delphi which relied on creating the 
>> main form 
>> manually, should something like that be attempted for Lazarus?
>>
>> Or should I simply redo the app so that the login is the main form?
>>
> 
> In the OnCreate handler for the main form, you can create your login form
> and do a showmodal of that form. In Oncreate the main form isn't visible
> yet. In case the user can't provide correct credentials, call
> application.terminate: under gtk2 the main form will never show, windows
> shows the main form in a very short flash which can be avoided by setting
> windowstate:=wsminimized; just before application.terminate.
> 
> procedure TFormMain.FormCreate(Sender: TObject);
> begin
>   FormLogin:=TFormLogin.create(self);
>   while true do
>     case FormLogin.showmodal of
>       mrAbort:
>         begin
>         windowstate:=wsminimized;
>         application.terminate;
>         break;
>         end;
>       mrOK:
>         break;
>     end;  
>   FormLogin.destroy;
> end;
> 
> This will loop on the login form until the user aborts (mrAbort) or the
> correct login credentials are provided (mrOK). You can do the credential
> check in the login form or in the mrOK case if you like.

Thanks Ludo, "clear as a bell" :-)

I'm already tinkering in various apps with getting things to happen at 
various times relative to the validity of the main form object, it just 
hadn't occurred to me that I could forcibly create a premature login form.

-- 
Mark Morgan Lloyd
markMLl .AT. telemetry.co .DOT. uk

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