Namespaces would help all around.
-e
Pablo Kang wrote:
We could minimize name conflicts if resources had namespaces. :|
On Wed, 29 Aug 2007, Elliot Winard wrote:
I don't know about removing the platform warnings.
If I include two libraries that have resources with conflicting
names, I want to know about it. For example - I might include
multiple libraries , each defining a 'logo' resource and expecting
the logo to be sized a certain way -
<include "mailwindow" />
<include "stockwindow" />
I want the compiler to tell me that the stockwindow's logo is
overwriting the mailwindow's logo. Warnings are informative,
non-fatal and should be used to provide this kind of information.
This proposal skirts CSS altogether. If this gets implemented as
proposed then the display of warnings should be configurable at
compile-time. I think it would be confusing to users if resources
(or classes or instances) get clobbered without any warning.
-e
Sarah Allen wrote:
I think this is an excellent proposal. cc'ing laszlo-user to see
if other folks developing in LZX have strong feelings about this ...
On Tue, Aug 28, 2007 at 3:12 PM, Bret Simister wrote:
Currently, in the OpenLaszlo platform, it was decided that declaring
a resource twice within an LZX app causes a server warning. This was
intended to help developers just in case they accidentally overrode
a resource that had already been declared in another library.
<!-- the following code produces a warning, but still compiles -->
<canvas>
<resource name="logo" src="logo.gif" />
<resource name="logo" src="logo2.gif" />
<!-- view appears with logo2.gif -->
<view resource="logo" />
</canvas>
At this time, I would suggest that the platform remove these
warnings and have the last resource declaration override all other
previous declarations.
Here is why...
OpenLaszlo now has a CSS implementation. It gives developers an
elegant method of skinning their applications. This works,
currently, by first declaring a resource
<resource name="someimage_rsc" src="somepath/someimage.jpg" />
and then referring to that resource in a CSS selector
view[name="someview"] {
resource: someimage_rsc;
}
If a developer builds a library ....
myCustomLibrary ( folder )
library.lzx
myresources.lzx ( contains many resource definitions including
'lowerRightCorner_rsc' )
mystyles.css ( contains many selectors including one that
references 'lowerRightCorner_rsc' )
... ( other class and source image files )
where library.lzx includes both myresources.lzx and mystyles.css
Then library can be used with a simple inclusion in the main app.
<canvas>
<include name="myCustomLibrary" />
<!-- instance of a class from myCustomLibrary -->
<mycustomclass />
</canvas>
Let's assume that " mycustomclass " contains a number of resources,
and that you ( as a developer )
only want to change one of those resources . The simplest method to
accomplish this would be ...
<canvas>
<include name="myCustomLibrary" />
<!-- override resource definition "lowerRightCorner_rsc" defined
earlier in myresouces.lzx -->
<resource name="lowerRightCorner"
src="my_new_path/my_lower_right_corner.jpg" />
<!-- instance of mycustomclass that will now display the
new resource based on the unchanged css selector -->
<mycustomclass />
</canvas>
Currently, this code would cause a compiler warning. To avoid these
warnings ( without changing OpenLaszlo ) the resouces.lzx file(s)
and possibly the library .lzx would have to be edited.
If instead, we allow for resource overriding, then ...
1) the original CSS and resource files will remain unchanged
2) The old resource for " lowerRightCorner" would NOT be included
in the app 3) There would be clean separation between external
libraries and the skinning of theses libraries included in an
application.
