[reportlab-users] From intra-paragraph images to drawings?

[Robin Becker]

On 08/05/2013 10:53, Dinu Gherman wrote:

> Hi,

>

> I wonder if anybody has tried to generalize the concept of intra-para-

> graph images to drawings? This would enable nice features like something

> called "sparklines", which have been introduced by Edward R. Tufte, if

> I'm not mistaken. See also this nice jQuery package:

>


I don't think it would be too hard to make a drawing produce an image that could 
be injected into a paragraph. The main problem would be how to identify the 
chart code and data in a sensible way. The img tags have a lot of control over 
height / width etc etc, but they don't need much more than a uri to identify 
them. Presumably one could inject a namespace into the parser somehow as is done 
for various other cases eg callbacks are identified by name and are assumed to 
live directly on the canvas


> 	func = getattr(tx._canvas,name,None)

> 	if not func:

> 		raise AttributeError("Missing %s callback attribute '%s'" % (kind,name))

> 		tx._canvas._curr_tx_info=dict(tx=tx,cur_x=cur_x,cur_y=cur_y,leading=leading,xs=tx.XtraState)

> 		try:

> 			func(tx._canvas,kind,cbDefn.label)

> 		finally:

> 			del tx._canvas._curr_tx_info


that might work for a drawable object



>    http://omnipotent.net/jquery.sparkline


I looked at the front page and it looks OK, but I wasn't able to see how 
data/chart type were selected for the charts; one of the paras is described thus


>  <p>

> Inline

> <span class="sparkline">

> <canvas style="display: inline-block; width: 21px; height: 16px; vertical-align: top;" width="21" height="16"></canvas>

> </span>

> line graphs

> <span class="sparkline">

> <canvas style="display: inline-block; width: 63px; height: 16px; vertical-align: top;" width="63" height="16"></canvas>

> </span>

> </p>


but the two charts are different so I guess the data / chart is being pushed 
into them via the class.



> Regards,

>

> Dinu

........

-- 
Robin Becker