Line Class / DrawHorizontalLine problems.

[xTrader1]

Hi,

I need an indicator, which looks like one in enclosed image - there is a red/yellow/green zone. The zones are just bunch of horizontal lines.

Values of the lines are computed parameters passed to the indicator.

I tried to create new Line objects during Initialize(). This approach works, however the lines are fixed - if I'm changing values of parameters, it seems Initialize() is not called, the lin values remain, but are not relevant anymore.

Therefore I tried to using DrawHorizontalLine() in OnBarUpdate() . I tried to ensure it's done only once e.g.
if (CurrentBar == 5)
{
for (i=y1 to y2)
{
strL = "Line" + i.ToString() ;
// Add(new Line(new Pen(Color.Red,3), i, strL));
DrawHorizontalLine(strL, true, i, Color.Red, DashStyle.Solid , 4) ;

}

for (i=y3 to y4)
{
strL = "Line" + i.ToString() ;
// Add(new Line(new Pen(Color.Yellow,3), i, strL));
DrawHorizontalLine(strL, true, i, Color.Yellow, DashStyle.Solid , 4) ;

}

for (i=y5 to y6)
{
strL = "Line" + i.ToString() ;
// Add(new Line(new Pen(Color.Green,3), i, strL));
DrawHorizontalLine(strL, true, i, Color.Green, DashStyle.Solid , 4) ;

}

This time NinjaTrader enters indefinite loop with 100% CPU utilization.
}

It seems, it's possible to use DrawRegion() , but I understand that in order to achieve the effect as in attached image, I should create 3 dummy data series and feed them with constant values in every bar. This approach seems to be resource consuming and I suspect there will be the same problem as described above with horizontal line, because I need to ensure DrawRegion is called only once in a particular bar.

Did I misunderstand something ? Any other solution ? Thanks.

[NinjaTrader_Bertrand]

xTrader1, correct for DrawRegion you would need two dataseries as region boundaries or one dataseries and a double value - http://www.ninjatrader-support.com/H...rawRegion.html

I don't think you need to create your horizontal line with a unique tag for each bar if you work with DrawExtendedLine - http://www.ninjatrader-support.com/H...endedLine.html

[xTrader1]

Drawing lines

xTrader1, correct for DrawRegion you would need two dataseries as region boundaries or one dataseries and a double value - http://www.ninjatrader-support.com/H...rawRegion.html

I don't think you need to create your horizontal line with a unique tag for each bar if you work with DrawExtendedLine - http://www.ninjatrader-support.com/H...endedLine.html

Much thanks for a quick reply.
Could you comment what's wrong trying to create new line objects in OnBarUpdate() event, doing it only once ? I forgot to mention that in this case I received just an empty indicator display - probably an exception was thrown, I don't know about.

What went wrong with DrawHorizontalLine that caused indefinite loop?


Eventually a suggestion, I think an important one. Please provide an event OnParameterChanged() which will be fired when user changes indicator/strategy parameters. If there is something like that undocumented, please let me know. I'm not going to ask support regarding such issue.

[NinjaTrader_Bertrand]

xTrader1, you're welcome - there's nothing wrong with your lines creation in the OnBarUpdate() but I think your loop is not incrementing correctly and thus never ending, please see this link for the various available loop commands in NinjaScript - http://www.ninjatrader-support.com/H...gCommands.html

Also: if you change parameters in your indicators and hit 'Apply' or 'Ok' the study will be recalculated based on your new inputs.

If you can live without the region coloring the easiest for you would be to use a Plot in the Initialize() for your needed lines - http://www.ninjatrader-support.com/H...deV6/Plot.html

For example like -

 
Add(new Line(Color.DarkGray, 80, "Upper2"));
Add(new Line(Color.DarkGray, 70, "Upper1"));

The y values for the lines are then adjustable under the 'Lines' paramter entry when you startup the indicator for display.