[Gambas-user] Getting an Object instance from a string

[nando]

...If I understand properly, I had a similar issue years ago.

You want to extend each class and override each with it's own personal .getproperty.
Dynamic dispatching will call the correct SUB

So, you want to wrap into a SUB the Object.GetProperty(sModule, "Var1")
so that it gets dynamically dispatched.

Although I know C++ doest this (which is how I solved my problem at that time)
my question for Benoit is does GAMBAS also work this way too?

-Fernando




---------- Original Message -----------
From: Sebastian Kulesz <sebikul at ...626...>
To: mailing list for gambas users <gambas-user at lists.sourceforge.net>
Sent: Thu, 29 Dec 2011 04:17:09 -0300
Subject: Re: [Gambas-user] Getting an Object instance from a string

> On Wed, Dec 28, 2011 at 11:20 PM, John Spikowski
> <support at ...2529...> wrote:
> > On Tue, 2011-12-27 at 22:03 -0300, Sebastian Kulesz wrote:
> >> Hi! I am having some problems when using the Object.GetProperty method
> >> when the object parameter to be used is stored in a string. The
> >> structure of my project is as follows
> >>
> >> ============
> >> Module Module1{
> >>
> >> public Var1 as string
> >>
> >> }
> >>
> >>
> >> ============
> >> Module Main (Starting class){
> >>
> >> public sub Main()
> >>
> >>     DIM sModule as String
> >>
> >>     sModule="Module1"
> >>
> >>     Object.GetProperty(sModule, "Var1")
> >>
> >> END
> >>
> >> }
> >> ============
> >>
> >> The normal behavior is to know the first parameter  of the GetProperty
> >> method, hence calling Object.GetProperty(Module1, "Var1"), but i need
> >> the first parameter to be dynamic, therefore being of a type different
> >> than object
> >>
> >> I would like to know if there is a way to get an instance of an object
> >> by knowing the class/module name, or if the GetProperty method can be
> >> modified to accept a string as a parameter, same as the second
> >> argument
> >>
> >> Thanks!
> >>
> > Benoît has already responded on this but I'm currious, before using
> > Gambas, were you using the IUP (Portable User Interface) GUI library?
> >
> > Your requests sounds very IUPish. ;-)
> >
> >
> 
> I understand that by looking this problem from the coding side, a
> pointer makes much sense. But my problem is this:
> I have a fixed set of modules. Each of them have the same properties
> and one method. By checking the user's system, a module may or may not
> be loaded and added into a treeview. Now, when the user clicks on a
> treeview item, I want to load the properties of the corresponding
> module. To do this, I can only know the selected module from the
> treeview key, which is a string that matches the module name.
> 
> The problem would be here, as I cannot tell the Object.GetProperty to
> fetch a property from this string.
> 
> I managed, though, to get around this problem. I just coded a huge
> select case function, which returns the object from a given string.
> But every time I add a module I have to add useless code that makes my
> app more error prone and less maintainable.
> 
> Thanks!
> 
> PD: I heard a few times about the IUP library, but I never actually used it ;)
> 
> ------------------------------------------------------------------------------
> Ridiculously easy VDI. With Citrix VDI-in-a-Box, you don't need a complex
> infrastructure or vast IT resources to deliver seamless, secure access to
> virtual desktops. With this all-in-one solution, easily deploy virtual 
> desktops for less than the cost of PCs and save 60% on VDI infrastructure 
> costs. Try it free! http://p.sf.net/sfu/Citrix-VDIinabox
> _______________________________________________
> Gambas-user mailing list
> Gambas-user at lists.sourceforge.net
> https://lists.sourceforge.net/lists/listinfo/gambas-user
------- End of Original Message -------