wxNotebook and wx_object

[Mazen Harake-2]

Hi,

Before I post a patch to erlang-patches I was just wondering if it these
two things are intended behaviour:

1) If I add  a Panel to Notebook (as a page) and then destroy the Panel,
I can then ask for the panel on the same index (wxNotebook:getPage/2)
and get a different panel. further more, if I have added a panel and
then ask for an index outside of the number of panels I get a new Panel
which I never created. Also, why does the page index start at 0 when
everything else in Erlang is 1 based (pretty much).

E.g:
Nb = wxNotebook:new(Parent, ?wxID_ANY, []),
Panel = wxPanel:new(),
wxNotebook:addPage(Nb, Panel, "Whatever", []), %% this is the first page
added
P1 = wxNotebook:getPage(Nb, 0), %% this gives the first page added (Panel),
PUnknown = wxNotebook:getPage(Nb, 1), %% this gives a new page... why?
shouldn't it crash or something?
wxPanel:destroy(Panel), %% delete the panel
P2 = wxNotebook:getPage(Nb, 0),
%% P1 /= P2 /= PUnknown

Is this intended behaviour? I don't have a patch for this because I
don't know what is expected

2) firstly, when calling wx_object:start_link/X and returning {stop,
whatever} it exits the process. Why?
second, it patternmatches the return value (from the ack) to {ok, Pid},
again: Why? This causes the return value to exit with badmatch, I'm sure
that is not intended? Or is it?

/Mazen

________________________________________________________________
erlang-bugs mailing list. See http://www.erlang.org/faq.html
erlang-bugs (at) erlang.org

[Dan Gudmundsson-2]

Hi

wx(Erlang) is just an erlang port of wxWidgets, it marshals the arguments and
make the corresponding C++ calls and so it behaves exactly the same as the
original wxWidgets.

Thus since wxWidgets is coded in C++ everything in wx starts from 0 and not 1.

I can't answer the first question since it's not a feature of wxErlang
you have to
send those kind of questions to wxWidgets list, I'm no expert of the
implementation
of wxWidgets.

Also I don't think you can depend on that behavior (unless it's
documented) for all
platforms.

Question 2, is should mimic the gen_server behavior, I'll have a look
how it's handled
there.

/Dan

On Sun, Sep 27, 2009 at 11:41 AM, Mazen Harake
<mazen.harake@...> wrote:

> Hi,
>
> Before I post a patch to erlang-patches I was just wondering if it these two
> things are intended behaviour:
>
> 1) If I add  a Panel to Notebook (as a page) and then destroy the Panel, I
> can then ask for the panel on the same index (wxNotebook:getPage/2) and get
> a different panel. further more, if I have added a panel and then ask for an
> index outside of the number of panels I get a new Panel which I never
> created. Also, why does the page index start at 0 when everything else in
> Erlang is 1 based (pretty much).
>
> E.g:
> Nb = wxNotebook:new(Parent, ?wxID_ANY, []),
> Panel = wxPanel:new(),
> wxNotebook:addPage(Nb, Panel, "Whatever", []), %% this is the first page
> added
> P1 = wxNotebook:getPage(Nb, 0), %% this gives the first page added (Panel),
> PUnknown = wxNotebook:getPage(Nb, 1), %% this gives a new page... why?
> shouldn't it crash or something?
> wxPanel:destroy(Panel), %% delete the panel
> P2 = wxNotebook:getPage(Nb, 0),
> %% P1 /= P2 /= PUnknown
>
> Is this intended behaviour? I don't have a patch for this because I don't
> know what is expected
>
> 2) firstly, when calling wx_object:start_link/X and returning {stop,
> whatever} it exits the process. Why?
> second, it patternmatches the return value (from the ack) to {ok, Pid},
> again: Why? This causes the return value to exit with badmatch, I'm sure
> that is not intended? Or is it?
>
> /Mazen
>
> ________________________________________________________________
> erlang-bugs mailing list. See http://www.erlang.org/faq.html
> erlang-bugs (at) erlang.org
>
>

________________________________________________________________
erlang-bugs mailing list. See http://www.erlang.org/faq.html
erlang-bugs (at) erlang.org

[Mazen Harake-2]

Hi,

Thanks for the reply, I agree that one shouldn't depend on that
behaviour, that is why I don't, but now at least I know it is not an
erlang "bug" per se.

/Mazen


Dan Gudmundsson wrote:

> Hi
>
> wx(Erlang) is just an erlang port of wxWidgets, it marshals the arguments and
> make the corresponding C++ calls and so it behaves exactly the same as the
> original wxWidgets.
>
> Thus since wxWidgets is coded in C++ everything in wx starts from 0 and not 1.
>
> I can't answer the first question since it's not a feature of wxErlang
> you have to
> send those kind of questions to wxWidgets list, I'm no expert of the
> implementation
> of wxWidgets.
>
> Also I don't think you can depend on that behavior (unless it's
> documented) for all
> platforms.
>
> Question 2, is should mimic the gen_server behavior, I'll have a look
> how it's handled
> there.
>
> /Dan
>
> On Sun, Sep 27, 2009 at 11:41 AM, Mazen Harake
> <mazen.harake@...> wrote:
>  
>> Hi,
>>
>> Before I post a patch to erlang-patches I was just wondering if it these two
>> things are intended behaviour:
>>
>> 1) If I add  a Panel to Notebook (as a page) and then destroy the Panel, I
>> can then ask for the panel on the same index (wxNotebook:getPage/2) and get
>> a different panel. further more, if I have added a panel and then ask for an
>> index outside of the number of panels I get a new Panel which I never
>> created. Also, why does the page index start at 0 when everything else in
>> Erlang is 1 based (pretty much).
>>
>> E.g:
>> Nb = wxNotebook:new(Parent, ?wxID_ANY, []),
>> Panel = wxPanel:new(),
>> wxNotebook:addPage(Nb, Panel, "Whatever", []), %% this is the first page
>> added
>> P1 = wxNotebook:getPage(Nb, 0), %% this gives the first page added (Panel),
>> PUnknown = wxNotebook:getPage(Nb, 1), %% this gives a new page... why?
>> shouldn't it crash or something?
>> wxPanel:destroy(Panel), %% delete the panel
>> P2 = wxNotebook:getPage(Nb, 0),
>> %% P1 /= P2 /= PUnknown
>>
>> Is this intended behaviour? I don't have a patch for this because I don't
>> know what is expected
>>
>> 2) firstly, when calling wx_object:start_link/X and returning {stop,
>> whatever} it exits the process. Why?
>> second, it patternmatches the return value (from the ack) to {ok, Pid},
>> again: Why? This causes the return value to exit with badmatch, I'm sure
>> that is not intended? Or is it?
>>
>> /Mazen
>>
>> ________________________________________________________________
>> erlang-bugs mailing list. See http://www.erlang.org/faq.html
>> erlang-bugs (at) erlang.org
>>
>>
>>    

________________________________________________________________
erlang-bugs mailing list. See http://www.erlang.org/faq.html
erlang-bugs (at) erlang.org

[Mazen Harake-2]

Any news on this? Is the pattern match going to be removed?

I had a look at gen_server, and that doesn't have a pattern match. Just
wanted to know because otherwise I will have to work around it because
currently I'm working with a hacked wx_object :)

Cheers,

/Mazen

Mazen Harake wrote:

> Hi,
>
> Thanks for the reply, I agree that one shouldn't depend on that
> behaviour, that is why I don't, but now at least I know it is not an
> erlang "bug" per se.
>
> /Mazen
>
>
> Dan Gudmundsson wrote:
>> Hi
>>
>> wx(Erlang) is just an erlang port of wxWidgets, it marshals the
>> arguments and
>> make the corresponding C++ calls and so it behaves exactly the same
>> as the
>> original wxWidgets.
>>
>> Thus since wxWidgets is coded in C++ everything in wx starts from 0
>> and not 1.
>>
>> I can't answer the first question since it's not a feature of wxErlang
>> you have to
>> send those kind of questions to wxWidgets list, I'm no expert of the
>> implementation
>> of wxWidgets.
>>
>> Also I don't think you can depend on that behavior (unless it's
>> documented) for all
>> platforms.
>>
>> Question 2, is should mimic the gen_server behavior, I'll have a look
>> how it's handled
>> there.
>>
>> /Dan
>>
>> On Sun, Sep 27, 2009 at 11:41 AM, Mazen Harake
>> <mazen.harake@...> wrote:
>>  
>>> Hi,
>>>
>>> Before I post a patch to erlang-patches I was just wondering if it
>>> these two
>>> things are intended behaviour:
>>>
>>> 1) If I add  a Panel to Notebook (as a page) and then destroy the
>>> Panel, I
>>> can then ask for the panel on the same index (wxNotebook:getPage/2)
>>> and get
>>> a different panel. further more, if I have added a panel and then
>>> ask for an
>>> index outside of the number of panels I get a new Panel which I never
>>> created. Also, why does the page index start at 0 when everything
>>> else in
>>> Erlang is 1 based (pretty much).
>>>
>>> E.g:
>>> Nb = wxNotebook:new(Parent, ?wxID_ANY, []),
>>> Panel = wxPanel:new(),
>>> wxNotebook:addPage(Nb, Panel, "Whatever", []), %% this is the first
>>> page
>>> added
>>> P1 = wxNotebook:getPage(Nb, 0), %% this gives the first page added
>>> (Panel),
>>> PUnknown = wxNotebook:getPage(Nb, 1), %% this gives a new page... why?
>>> shouldn't it crash or something?
>>> wxPanel:destroy(Panel), %% delete the panel
>>> P2 = wxNotebook:getPage(Nb, 0),
>>> %% P1 /= P2 /= PUnknown
>>>
>>> Is this intended behaviour? I don't have a patch for this because I
>>> don't
>>> know what is expected
>>>
>>> 2) firstly, when calling wx_object:start_link/X and returning {stop,
>>> whatever} it exits the process. Why?
>>> second, it patternmatches the return value (from the ack) to {ok, Pid},
>>> again: Why? This causes the return value to exit with badmatch, I'm
>>> sure
>>> that is not intended? Or is it?
>>>
>>> /Mazen
>>>
>>> ________________________________________________________________
>>> erlang-bugs mailing list. See http://www.erlang.org/faq.html
>>> erlang-bugs (at) erlang.org
>>>
>>>
>>>    
>
>
> ________________________________________________________________
> erlang-bugs mailing list. See http://www.erlang.org/faq.html
> erlang-bugs (at) erlang.org
>

________________________________________________________________
erlang-bugs mailing list. See http://www.erlang.org/faq.html
erlang-bugs (at) erlang.org