I have been thinking about that and I have some ideas. But I would like to
understand how often that use case actually comes up. I know CSS supports it,
but in practice (in Pivot specifically) I wonder how important it is?
On Jul 2, 2010, at 7:30 PM, Michael Allman wrote:
> Hi Greg,
>
> How would one specify multiple named styles for a component element? Like
>
> <PushButton styles="redButton bigFont"/>
>
> Cheers,
>
> Michael
>
> On Fri, 2 Jul 2010, Greg Brown wrote:
>
>> Hi all,
>>
>> I have been thinking about this and I think I have a fairly elegant solution
>> that will also significantly extend the capabilities of BXMLSerializer. I am
>> thinking of extending the <bxml:include> tag to support loading of arbitrary
>> content. Currently, it only supports includes of other BXML files, but there
>> is no reason that it couldn't be modified to include other types, such as
>> JSON, XML, or even images. All we'd have to do is determine an appropriate
>> serializer to use for the include - this could be inferred based on file
>> extension or could be specified explicitly via a "mimeType" attribute to the
>> include tag. The MIME type-to-serializer mappings could be configurable such
>> that an include could literally be used to load any type of object.
>>
>> One application of such an extension would be styling. <bxml:include> could
>> be used to load a "stylesheet" - a JSON file containing a "map of maps". The
>> format of this file would be identical to the format I had been considering
>> for the "named styles" approach - each key/value pair in the file would
>> essentially represent a "style class". For example, the following JSON file
>> would define a "redButton" class:
>>
>> { redButton: {
>> backgroundColor: "#aa0000",
>> color: "#ffffff"
>> }
>> }
>>
>> In a BXML document, this file could be included as follows:
>>
>> <bxml:include bxml:id="styles" src="styles.json"/>
>>
>> The "redButton" style could then be applied to a button as follows:
>>
>> <PushButton styles="$styles.redButton"/>
>>
>> Unlike the previous solution I proposed, this approach would require no
>> changes to the Component or Container classes whatsoever. With the exception
>> of extending the <bxml:include> tag, it relies entirely on existing
>> functionality (and existing BXML syntax, so developers will already be
>> familiar with it).
>>
>> There are obviously other applications as well. Some simple examples:
>>
>> <TableView>
>> <tableData>
>> <bxml:include src="table_data.json"/>
>> </tableData>
>> </TableView>
>>
>> <TreeView>
>> <treeData>
>> <bxml:include src="tree_data.xml"/>
>> </treeData>
>> </TreeView>
>>
>> One challenge might be how to specify the MIME/serializer mapping for an
>> include (we won't want BXMLSerializer to include all possible mappings by
>> default). This could be inherited from the parent serializer, but I think
>> that a BXML syntax for specifying it in markup is probably a good idea.
>>
>> Anyway, I think this would be an extremely flexible and useful addition to
>> the serializer, and I think it also handles the styling case pretty well.
>> Let me know what you think.
>>
>> G
>>
>>
>> On Jul 2, 2010, at 1:34 PM, Greg Brown wrote:
>>
>>> FYI, named styles are turning out to be a lot more challenging than I
>>> expected. The solution I proposed the other day doesn't work - elements in
>>> BXML aren't added to the parent element until the end tag is processed. So,
>>> given the following structure:
>>>
>>> <Window styleClasses="{foo:{...}}">
>>> <BoxPane>
>>> <PushButton styleClass="foo"/>
>>> </BoxPane>
>>> </Window>
>>>
>>> when the styleClass attribute of the PushButton is processed, the BoxPane
>>> hasn't yet been added to the Window, so the "foo" style class name resolves
>>> to null. :-(
>>>
>>> I'll keep thinking about it, though. Suggestions are welcome.
>>>
>>> Thanks,
>>> G
>>>
>>
