[OpenLayers-Users] Google Summer of Code 2008

[Stephen Woodbridge]

Andrew,

Along these lines, I have had to overload some OL methods to get the 
behavior I wanted. So mostly I have not patched OL for my own purposes.

You can see this on my geofence editor (a work in progress) at
   http://imaptools.com/~woodbri/edit/index26.php?extent=-129,19+-60,60

I am using svn at the moment because it has a lot of features and fixes 
in feature editing code that I am referencing. Of course working in svn 
has some risks I have found it to be very stable. An the only changes I 
have had to workaround are bug fixes  and small changes the link page above.

For my two cents, I love the idea of plugins. I believe that if you 
build a plugin and later change OL version, you should be reasonably 
protected but now 100%. Like if the plugin uses from core features of OL 
that have been totally rewritten or replaced.

I yo have lots of application code that is dependent on some given 
version of OL, then you can give each  a unique name like:

/js/OpenLayers/2.4/OpenLayers.js
/js/OpenLayers/2.5/OpenLayers.js
/js/OpenLayers/2.5p1/OpenLayers.js  // patched version of OL2.5
/js/OpenLayers/svn/2008-03-12/OpenLayers.js

And then load the appropriate on in you HTML.

-Steve W

Andrew de Klerk wrote:
> Chris 
> 
> Thanks for the insightful reply. If I am hearing you correctly, I could
> include,  for example, the enhanced layer switcher through an additional
> script tag. Would this override the existing layer switcher?, or would I
> need to compile openlayers with the layer switcher excluded. This is
> essentially what I was referring to, but you have answered my question. 
> 
> The problem I was trying to get to, is if you replace controls etc within
> the main openlayers script, and a new release comes out, you would need to
> keep track Of what you have modified and apply that to the new version - I
> would like to keep away from that. A classic example is the styling of the
> map tools etc - we have changed their colours, and I currently have
> commented placeholders in the code so that when new versions come out, I can
> go and modify them again (although I realize that this is due to be moved to
> the stylesheet)
> 
> I was unaware of the addin section and will read through that to educate
> myself a bit more.
> 
> .....looking forward to 2.6!
> 
> Thanks
> Andrew
> 
> -----Original Message-----
> From: users-bounces at openlayers.org [mailto:users-bounces at openlayers.org] On
> Behalf Of Christopher Schmidt
> Sent: 12 March 2008 03:01 PM
> To: users at openlayers.org
> Subject: Re: [OpenLayers-Users] Google Summer of Code 2008
> 
> On Tue, Mar 11, 2008 at 11:45:43PM -0700, Andrew de klerk wrote:
>> Hi all
>>
>> I have had a look at the trac for this cited on the dev mailing list, and
> am
>> not sure if this is the appropriate place for this suggestion, but here
>> goes.
>>
>> Linda Rawson suggested to include plugin development for openlayers as
> part
>> of te summer of code. I was reminded of this when I saw the post by Jachym
>> Cepicky about his customised layerswitcher. In many cases as users, we
> would
>> like to use the most stable release eg 2.5, but sometimes need/want to use
>> enhancements such as this layerswitcher, or a scalebar etc. Currently the
>> only way is to download from trunk etc and essentially create your own
>> custom version of openlayers. 
> 
> I'm not sure that this is true? Certainly, if code would work with 2.5,
> you can simply include an additional script tag in your page (one for
> OL, one for your extra code).
> 
> This is essentially the design of the 'Addins' program we've set up.
> http://trac.openlayers.org/wiki/Addins tells more about this, and you
> can see that there is already the ScaleBar addin.
> 
>> I forsee this being a problem when future
>> release are released. 
> 
> I'm not sure I see the problem. Can you explain?
> 
>> I would like to see the development of a core base
>> with the ability to "plugin" these great enhancements. As it stands I
> would
>> already plugin the scalebar and the enhanced popups. 
> 
> The new popups belong in trunk, because in order to work, they need to
> work at a lower level. In general, I believe that Controls are most
> likely the case where 'Addins' is most appropriate, becasue they provide
> functionality that is dependent, but not *inter-*depenednet, on the
> core. (In other words: they depend on core, core doesn't depend on
> them.) It's unfortunate that the new popups have taken so long, but
> that doesn't mean that they're really a good fit for living outside of
> trunk.
> 
>> I have resisted trying
>> to create my own custom version in fear of breaking something.
> 
> Sure, understandably. That's part of the point of addins: you have a
> clear 'line' between what is trunk and what isn't, and although you can
> build a single file build with addins, it's not really neccesary.
> 
> http://dev.openlayers.org/addins/scalebar/trunk/examples/scalebar.html
> 
> is an example: clearly, it works with trunk, but that doesn't mean it
> has to be *in* the build to work.  
> 
> Regards,