Bret mentioned placing the responsibility on the library developer is
preferable.
I think that both would be useful.
-e
Henry Minsky wrote:
Having a "replace is ok" flag seems like a good solution. I wonder
which would be preferable, placing the declaration on the base library
defs, or would the user put it in their code when overriding? Or
both?
On 8/29/07, Sarah Allen <[EMAIL PROTECTED]> wrote:
That is exactly the dilemma. The tension is between a the frustration of an
accidental override and the frustration if you want to set up your library
to allow customizing a resource, where you have to provide a resource file
and library separately and then the user of the library needs to create a
new resource file and include all your resources except the logo and include
the logo.
I suppose there could be some kind of flag that says that I meant to
override this resource, like:
<resource name="logo" src="logo.png" replace="true"/>
I don't know if that would complicate the implementation or the language
folk would consider it weird, but as a user of the language it would work
for me.
Sarah
On Wed, Aug 29, 2007 at 5:01 AM, 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.
