Dynamically set flash chart height?

Question

Hi,
I have a flash chart that includes a selector that alters the query for the chart. Depending on what the user selects, the chart shows a different number of rows (this happens to be a stacked horizontal bar chart, but this could apply to any chart type). I would like to be able to dynamically set the chart height based on the number of rows the query returns. If I set it too small and the user makes a choice that returns a larger number of rows, the chart bars are compressed to the point where the labels are unreadable or omitted altogether. Conversely, if I set the height to a larger value and the user makes a selection that results in a small number of rows, the chart is overly extended and hard to read.
I am able to calculate what I'd like the chart height to be using a page item and a before header process. But I can't figure out how to pass this value to AnyChart. I tried using an item substitution (e.g., &P7_CHART_HEIGHT.) as the value for the chart height on the Chart Attributes/Chart Settings page, but this attribute requires a non-zero numeric value. I tried to figure out if I could alter the chart XML, but could not figure out how to do it and I'm not sure item substitutions would be passed in the XML anyway.
Is there a way to dynamically set the height attribute of a chart at page load time?
Thanks,
Mike

Answer 1

Hi Mike,
You can update the Region Source of your chart, replacing the substitution strings *#HEIGHT#* with the reference to your page item *&P7_CHART_HEIGHT.*. So your chart region source should then look something like the following(note that I've trimmed some lines for display purposes), and when the chart is run it will pick up your setting for the height, based upon the value returned from your Before Header process:
<object classid="clsid:D27CDB6E-AE6D-11cf-96B8-444553540000"
    codebase="#HOST_PROTOCOL#://download.macromedia.com/pub/shockwave/cabs/flash/swflash.cab#version=6,0,0,0"
    width="#WIDTH#"
    height="&P7_CHART_HEIGHT."
    id="#CHART_NAME#"
    align="top">
<param name="movie" value="#IMAGE_PREFIX#flashchart/anychart_5/swf/...............................">
<param name="quality" value="high">
<param name="allowScriptAccess" value="sameDomain">
<param name="allowNetworking" value="all">
<param name="scale" value="noscale">
<param name="wmode" value="transparent">
<param name="FlashVars" value="initText=#FLASH_INIT#&xmlLoadingText=............................................">
<embed src="#IMAGE_PREFIX#flashchart/anychart_5/.......................................
       quality="high"
       width="#WIDTH#"
       height="&P7_CHART_HEIGHT."
       name="#CHART_NAME#"
       scale="noscale"
       align=""
       allowScriptAccess="sameDomain"
       allowNetworking="all"
       type="application/x-shockwave-flash"
       pluginspage="#HOST_PROTOCOL#://www.macromedia.com/go/getflashplayer"
       wmode="transparent"
       FlashVars="initText=#FLASH_INIT#&xmlLoadingText=#FLASH_................................................">
</embed>
</object>
#CHART_REFRESH#
{code}
I hope this helps.
Regards,
Hilary