Call GetYByValue() - ChartScale and GetXByBarIndex() - ChartControl in OnBarUpdate()

[lakman184]

Hi,

is there a way to call the methods mentioned above in the OnBarUpdate() method? I try to prepare my data in the OnBarUpdate method in order to render custom drawings in OnRender() Method.

Thanks,
Lukas

[NinjaTrader_Emily]

Hello Lukas,

Thank you for your post.

The ChartScale and ChartControl are provided by OnRender, so these should be used in OnRender():
protected override void OnRender(ChartControl chartControl, ChartScale chartScale)
{
}

The best practice is to precompute/prepare any values used for these methods instead of calculating them in OnRender(), which means setting the value you'd like to pass into GetYByValue() in OnBarUpdate by saving it to a variable, and then using that variable inside of the method in OnRender() or saving the bar index you would like to use to a variable (if it is not static) inside of OnBarUpdate() prior to passing it into the GetXByBarIndex() method in OnRender().

Another helpful practice that is generally more efficient is to use conditions to trigger your code for GetYByValue() or GetXByBarIndex(). This way the code is only triggered when it is needed instead of every time OnRender() is called.

There are some OnRender() performance practices listed on the following page:

https://ninjatrader.com/support/helpGuides/nt8/index.html?ninjascript_best_practices.htm#Performance

Please let us know if we may be of further assistance.