Area series null points

[jhhd]

I am trying to create a timeline using the TAreaSeries. Its aim is to show what regions data is present for, and as such the Y-axis is not applicable.

I am trying to add data through the use of regions:

Code: Select all

for (int i = 0; i < iNumRegions; ++i)
{
  pSeries->AddX(pRegions[i].dStart);
  pSeries->AddX(pRegions[i].dEnd);
  pSeries->AddNull();
}

with the intention being that if my regions array has two items, one which is 10->20, and one which is 40->50, I would get two areas with a blank gap inbetween.

The above code causes one area from start to end (10->50 in this case), with lines at the boundaries.

Am I missng something?

[Narcís]

Hi jhhd,

Code below does what you request using TeeChart Pro v8.02 VCL. Which TeeChart version are you using? Could you please check if this code works fine at your end?

Code: Select all

  Series1.Add(10);
  Series1.Add(20);
  Series1.AddNull('');
  Series1.Add(40);
  Series1.Add(50);

Thanks in advance.

[jhhd]

That works, but the figure in the Add() function refers to the Y-value, auto-incrementing the X-value, does it not? I have X-data, and don't care for Y-values.

If I could attempt to illustrate what I want:

Code: Select all

 #######     ################           ############################
 .     .     .     .     .     .     .     .     .     .     .     .
Jan   Feb   Mar   Apr   May   Jun   Jul   Aug   Sep   Oct   Nov   Dec

DateTime values are stored as doubles, so using simply Add() wouldn't work (as far as I could tell).

I am using TChart Pro v7.05.

Thanks.

[Narcís]

Hi jhhd,

Ok, in that case you should use AddXY adding X DateTime values and a constant Y value.

[jhhd]

For me, the following code doesn't work (there are no gaps):

Code: Select all

Series1.AddXY(10, 1);
Series1.AddXY(20, 1);
Series1.AddNull('');
Series1.AddXY(40, 1);
Series1.AddXY(50, 1);

[Narcís]

Hi jhhd,

Sorry, yes, this is because AddNull adds a point to X position being Series1.Count, you shoud do something like this:

Code: Select all

  Series1.AddXY(10, 1);
  Series1.AddXY(20, 1);
  Series1.AddNullXY(30,0);
  Series1.AddNullXY(35,0);
  Series1.AddXY(40, 1);
  Series1.AddXY(50, 1);

[jhhd]

Ah ha!

And it appears possible to simply do:

Code: Select all

for (int i = 0; i < iNumRegions; ++i)
{
  pSeries->AddXY(pRegions[i].dStart, 1);
  pSeries->AddXY(pRegions[i].dEnd, 1);
  pSeries->AddNullXY(pRegions[i].dEnd, 1);
}

Thanks for the quick help.