How to declare dependent style names with UiBinder

Question

I have a simple UiBinder widget containing a TextArea:

<!DOCTYPE ui:UiBinder SYSTEM "http://dl.google.com/gwt/DTD/xhtml.ent"> <ui:UiBinder xmlns:ui="urn:ui:com.google.gwt.uibinder"     xmlns:g="urn:import:com.google.gwt.user.client.ui">      <g:TextArea visibleLines="3" /> </ui:UiBinder> 

I want to control the background color of this textarea for writeable and read only states. GWT uses the "-readonly" style name decorator to achieve this. So I try this:

<!DOCTYPE ui:UiBinder SYSTEM "http://dl.google.com/gwt/DTD/xhtml.ent"> <ui:UiBinder xmlns:ui="urn:ui:com.google.gwt.uibinder"     xmlns:g="urn:import:com.google.gwt.user.client.ui">      <ui:style>         .textBoxStyle {             background-color:yellow;         }         .textBoxStyle-readonly {             background-color:lightgray;         }     </ui:style>      <g:TextArea styleName="{style.textBoxStyle}" visibleLines="3" /> </ui:UiBinder> 

Obviously this won't work because style names are obfuscated for CssResources resulting in something like this:

.G1x26wpeN {     background-color:yellow  } .G1x26wpeO {     background-color: lightgray; } 

The result HTML for writeable textarea looks like this:

<textarea tabindex="0" class="G1x26wpeN" rows="3"/> 

The read only textarea looks like this:

<textarea tabindex="0" class="G1x26wpeN G1x26wpeN-readonly" readonly="" rows="3"/> 

How do I declare the style so GWT will obfuscate the primary part but not the "-readonly" decdorator?

I know that I can disable the obfuscation for the entire style name. But I'd like to keep the obfuscation while making use of the decorators.

Answer 1

At this moment (GWT 2.4) it is not supported, and it's not clear if/when it will be supported, see issue 4746 in the GWT issue tracker.

The workaround is to add @external, which disables obfuscation for those styles. In this case that would be:

@external textBoxStyle, textBoxStyle-readonly; 

Answer 2

If you want to use this style for all your read-only TextAreas then I'd suggest just modifying the .gwt-TextArea-readonly style in your GWT theme CSS file.
Otherwise, I can only think of adding your custom style programmatically when you set the TextArea read-only.

PS: from the docs:

<set-configuration-property name="CssResource.obfuscationPrefix" value="empty" />` can be used for minimal-length selector names, but this is only recommended when the GWT module has total control over the page.  

I recommend using this (with "empty" or "X" or other unused prefix) for much shorter class names - because at default settings you don't gain that much through obfuscation (textBoxStyle - 12chars, G1x26wpeN - 9chars, X0 - 2 chars ;)).