[Laszlo-dev] Feature proposal: Add CSS2 box model support (padding, margins, borders) to views

[Raju Bitter]

I like that approach. We already had the same discussion earlier this year: how to manage a quickly increasing number view attributes once we implement more and more of CSS2/CSS3 across runtimes. Using mixins will redruce complexity in the documentation as well, keeping the number of attributes lower for classes.

But here's an interesting question: does the documentation support mixins? If not, that's a huge problem!

- Raju

On Dec 3, 2009, at 9:21 PM, Max Carlson wrote:

> That's done :)
> 
> Rami Ojares / AMG Oy wrote:
>> Just remember that Henry still needs to implement mixins for instances.
>> Or is that already done?
>> - rami
>> Max Carlson wrote:
>>> Agreed!  A mixin is the way to go.  I'll fix up the change, now that the riskier version has been backed out.
>>> 
>>> Rami Ojares / AMG Oy wrote:
>>>> I am currently so in love with the mixins that I recommend that approach
>>>> <view with="boxmodel" padding=".."/>
>>>> 
>>>> - rami
>>>> 
>>>> P T Withington wrote:
>>>>> I think this is a great feature, but that it is too close to the end of the 4.7 cycle to put in.  We can't just add a whole bunch of public slots to <view> without more community feedback.
>>>>> 
>>>>> If you want to 'try this out', I would suggest putting these attributes in another 'namespace'.  E.g., name the attributes `future$padding`, etc. (pick your meaningful prefix).  That way, people who want to take advantage of this code can, and their code will be easily marked so they can adapt it when we finalize the API, but we will greatly reduce the likelihood of breaking existing applications that subclass <view>.  I think it is correct to use the real CSS names for how these attributes would be controlled by a style sheet.  So you would do something like:
>>>>> 
>>>>> <attribute name="future$padding" value="0" style="padding" />
>>>>> 
>>>>> etc.
>>>>> 
>>>>> Of course, there is the issue that CSS actually specifies many of its box-model attributes as 'trbl' vectors.  For animation purposes, you probably want each vector component to be a separate attribute.  For API compactness, you probably just want a single vector for each of, margin/border/padding.  Border also has a pile of other attributes, not just the trbl dimensions...
>>>>> 
>>>>> Bottom line, I think we should defer implementation of this to 4.8.  If you _must_ have it in 4.7, please 'namespace' it.
>>>>> 
>>>>> And let's discuss what the ideal 4.8 API should be.
>>>>> 
>>>>> [One other approach would be to break out the box-model extension as a mixin, which would essentially namespace it because you'd have to explicitly request it in a `with` clause.]
>>>>> 
>>>>> On 2009-12-03, at 13:43, Max Carlson wrote:
>>>>> 
>>>>>> See here for more details on how box model works:
>>>>>> http://www.w3.org/TR/CSS2/box.html#box-dimensions
>>>>>> 
>>>>>> I propose adding four attributes to view, to support CSS2 box model:
>>>>>> 
>>>>>> padding: Specifies the number of pixels used for padding around the view
>>>>>> margin: Specifies the number of pixels used for margins inside th view.
>>>>>> borderwidth: Specifies the width of the border, in pixels.
>>>>>> bordercolor: Specifies the color of the border, as a CSS color value.
>>>>>> 
>>>>>> The risk is, padding, border and margin may be used in existing applications.  I already found a case in lz/tabs.lzx that used 'padding'.  In most cases, these attributes can simply be renamed.
>>>>>> 
>>>>>> Please send your thoughts!  I'd like to get this finalized in time for the 4.7 release.
>>>>>> 
>>>>>> -- 
>>>>>> Regards,
>>>>>> Max Carlson
>>>>>> OpenLaszlo.org
>>>>> 
>>>>> 
>>> 
> 
> -- 
> Regards,
> Max Carlson
> OpenLaszlo.org