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LablGTK Reading Properties
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Date: -- (:)
From: Gregory Malecha <gmalecha@r...>
Subject: Re: [Caml-list] LablGTK Reading Properties
I've modified the function and I'm still getting the same behavior. Here 
is my new code:

let points item =
  let prop = {Gobject.name = "points";
          Gobject.conv = GnomeCanvas.Conv.points} in
  let x = Gobject.get prop item in
  match x with
    None -> print_string "NONE!\n"; []
  | Some ary ->
      print_string "SOME!\n";
      Array.to_list ary

Is there a particular thing that I have to do before I can get the 
points? Does anyone have an example where they are able to do this?

Thanks.

Olivier Andrieu wrote:
> Hi,
>
> On Feb 5, 2008 5:39 PM, Gregory Malecha <gmalecha@rice.edu> wrote:
>   
>> Hi,
>>
>> I've been working on some code with GnomeCanvas and I'm having
>> difficulty reading properties off of objects. For example, I've created
>> a polygon and I want to read the points from it, but I always get back
>> None. Here's my current code:
>>
>> let points item =
>>   let prop = {Gobject.name = "points";
>>           Gobject.conv = GnomeCanvas.Conv.path_def} in
>>   let x = Gobject.get prop item in
>>   match x with
>>     None -> print_string "NONE!\n"; [] (* I always end up in this case *)
>>   | Some ary ->
>>       print_string "SOME!\n";
>>       let ary = GnomeCanvas.Conv.get_points ary in
>>       Array.to_list ary
>>     
>
> you're getting None because you're using the wrong conversion
> function: this "points" property is basically a float array and here
> you're using the path_def conversion which is for bpath (bezier path).
>
> Your code should work with:
>     let prop = {Gobject.name = "points"; conv = GnomeCanvas.Conv.points} in ...
>
>   

-- 
gregory malecha
wiess college
computer science
219.510.3400