How can I implement a stock volume chart using core plot on iPhone?

Question

I'm writing a stock charting application on iPhone using core-plot. What kind of chart should I use to plot the volume chart? Since I will also need to overlay the price charts onto the volume chart, how should I go about doing this?

Here's an image for reference (By no means am I trying to reimplement stockcharts functionality, just wanted to create a simple charts with volume information overlaid on the price charts):

example http://www.imagechicken.com/uploads/1264166887000577000.png

Thanks!

Answer 1

What about using a Javascript charting library inside a WebView for your charts? You could then use something like Emprise: http://www.ejschart.com/

Answer 2

If you look at the latest builds of the framework, Drew just added an open-high-low-close plot type, which is a CPTradingRangePlot with a CPTradingRangePlotStyleOHLC plot style. For an example of this in action, along with a bar chart tracking trading volume, see the latest version of the AAPLot example application that ships with the framework:
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