Re: Are multiple mainwindows possible?

On Sep 2, 2009, at 12:44 , Konovalov, Vadim (Vadim)** CTR ** wrote:

>> From: Michael Carman [mailto:[email protected]]
>> Does Tkx (or perhaps it would be Tcl.pm) support multiple  
>> mainwindows?
>> This doesn't complain, but even though $x and $y have different
>> addresses they refer to the same Tk widget.
>>
>>    my $x = Tkx::widget->new('.');
>>    my $y = Tkx::widget->new('.');
>>
>> That's not surprising since they have the same name. Methods like
>> _parent() and _kid() exploit this to "retrieve" the widget reference
>> from the Tcl name. Giving $x and $y different Tcl names doesn't  
>> appear
>> to be an option, either. Most of my attempts ended in "bad window  
>> path
>> name" errors. While there are lots of examples of using '.'
>> as the name
>> of the root window and it appears to be a requirement, the
>> documentation
>> never actually explains it.
>>
>> It looks like multiple mainwindows are not possible, in which
>> case I can
>> safely ignore that aspect of the Tk behavior. Is this true?
>
> In my vision, in tcl/tk world there is only one mainwindow (a  
> toplevel with path '.'), but this is per interpreter.
>
> With tk-enabled Tcl.pm you could do
>
> my $interp2 = $interp1->interp('create');
> and have another mainwindow for $interp2.

Dealing with multiple interpreters seems like a pain to me.  Multiple  
toplevels is the way to go.

> As it seems to me, the Tkx package creates only one tcl interpreter  
> within Tkx::i package and does not expose it to the user. So it  
> seems to me that seconf interpreter is not possible for Tkx, but  
> could be possible with a minor modifications to Tkx.

I would think that Tkx::interp_create("slavename") will allow you to  
create multiple interpreters from Tkx.  I have not tried to use this  
myself.  I never felt the need.

> On the contrary, in Tcl::Tk any widget has "interp" method, which  
> gives you an instance to widget's interpreter, so it is possible to  
> create another one, but I never used that feature, may be it is  
> never needed...
>
> Which makes me wonder - is my understanding true, that in Tkx a user  
> is not allowed to do tcl/tk's evals?

Tkx::eval() works fine since "eval" is a Tcl command too.

--Gisle

> IMO, this is a really nice feature! Really powerful!
>
> Best regards,
> Vadim.