I thinks there is a misunderstanding. My proposal is just to not provide the
convenience constructor, so instead of:
new ButtonCell(resources);
You'd do:
new ButtonCell(new DefaultAppearance(resources));
Making it crystal-clear that your ButtonCell is using DefaultAppearance. The
convenience constructor leads you to believe you're using "resources"
together with the Appearance you bound in the .gwt.xml -- which is not true:
you are using DefaultAppearance no matter which <replace-with> you provided.
Sorry, that is far better, but there still is a problem. With that way of
doing things is then you've lost your ability to use the .gwt.xml file to
swap out the Appearance as you're now using a new instead of a GWT.create.
Now, addStyleName is very limited since you can only style the wrapping
<div>. It's good enough to add blank padding, but it wont let you make the
internal part of the button wider or taller... Unless you use CSS type
selectors but, as Stephen points out, this makes the app dependent on a
specific widget style, and the app breaks as soon as this widget DOM
structure changes. (So you can't easily upgrade to newer styles.)
In fact, I almost wish CellWidgets did not have a addStyleName given that
it's really not that useful. I would rather have a slightly richer set of
semantic styling methods in Appearance and having ways to access them from
ButtonWidget (and UiBinder).
All true, I guess if I'm looking to alter the height/width of a cell
widget's internals or its internal structure I would expect to extend the
bundle. If I'm just looking to do things like set the float, padding/margine
addStyleName is the perfect tool. Maybe there is a better way for dealing
with boilerplate code, maybe with UiBinder as the hook. I'm not sure I'm
still a little foggy on the best practices when dealing with CssResources
especially with UiBinder.
Another option would be an enhancement GEP to make it codegen that
boilerplate for you. Admittedly it doesn't get rid of the code smell, but it
does save your fingers some work.
--
http://groups.google.com/group/Google-Web-Toolkit-Contributors
