Courage, Thank you so very much for your help so far!
After a sanity break, I got my app up in Tcl::Tk in Perl/Tk compatability mode. I've been reading demos, docs, and articles. This is the Tcl/Tk code that I think I need to run (followed by my questions): 
package require tkdnd
dnd bindsource .perl_hlist_object text/uri {\&Perl_Sub}
bind .perl_hlist_object <1> {dnd drag %W}

[download]

1) Do I need the interp object to setup DnD?

I can start a Tcl::Tk GUI in one of two ways: 
my $mw = MainWindow->new;    #Gives me the main window object, but not
+ the interpreter
my $interp = new Tcl::Tk;    #Gives me the interpreter, but not the ma
+in window

[download]

Do I need both objects? I think I need the interp object to make DnD calls, and the main window object to use perl/Tk compatability mode syntax. Is there a way to get both objects? Should I rewrite the GUI in Tcl/Tk syntax?

2) Can I get a Tcl/Tk path from a perl widget object?

This is related to #1. I can get object for a Tcl/Tk path with: my $hlist = widget(".f03.hlist01"); However, I have the ojbect and I think I need the path to set up DnD.

3) How do I make the actual calls?

Here's my stab at the Tcl/Tk objects under Tcl::Tk in perl (I haven't tested this because of #1):

My $i = new Tcl::Tk;
(... generate GUI ...)
$i -> call("package require", "tkdnd");
$i -> call("dnd bindsource", ".perl_hlist_object", "text/uri", {\&Perl
+_Sub});
$i -> call("bind", ".perl_hlist_object", "<1>", {dnd drag %W};

[download]
Is this correct, are there any gotchas?

  1. Can I put a use a perl object instead of a Tcl/Tk path (i.e. $results_l instead of .f03.hlist01)?
  2. Is the script on line 4 expecting a Tcl sub, or can I call a perl sub? Is there a special syntax?
  3. I don't understand the reference to %W. It's "The window the event is delivered to", and it doesn't make sense to me in this context. Would I leave it %W, or do I need to provide a value?
I greatly appreciate any help in this. It feels like I'm close, but I don't know where to look for the 'last mile'.

In reply to Tcl::Tk GUI working - Help with TkDnD through perl? by Ardemus
in thread Tk Drag and Drop Between Applications by Ardemus

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