Steema Central

Hi. I've noticed some strange behaviour with axes not being displayed on polar charts. My system has: Windows XP Pro (SP2), RAD Studio (so it's Delphi 2007) and TeeChart 8.02 (full source version). Don't know if this happens in other versions too.

Here's the simplest way to replicate the problem:

* Open a new VCL forms application (Delphi for Win32)
* Drop a TChart on the form
* Set AxisBehind to false
* Add two Polar series
* Deactivate the bottom of the two series

The top series still displays, but all the axes, ticks, labels and grid lines vanish. The problem still persists at runtime - it's not just a bug in the design environment. Axes return if you set AxisBehind to true, but sometimes that's not what you want...

Do you have any idea why it's happening?

Nick

edit:

I've found a work-around. The problem only occurs when AxesBehind is false and the bottom polar series (or polar-derived series, such as wind rose) is disabled. So, to stop it happening:

* Create an extra polar series
* Set its data source to Manual, and only put in data points you know are going to be in the region of interest
* Make its Pen and Point properties invisible and untick Show In Legend (so it won't ever be seen)
* Ensure it's the bottom listed series and that it's enabled

That seems to work. Strange behaviour, though. So I'd still be interested to know why, if you have any idea.

Hello Nick,

I've tried to reproduce the problem here with no luck, what do you mean when you say : * Deactivate the bottom of the two series ? Do you mean make bottom axes invisible ?

Hi Pep,

Sorry - I wasn't to clear about that. What I mean is:

When you double-click on the form's TChart component, and get the Chart Editor tool, it displays a list of the series you have. Untick the bottom one of those in the list and you should see the bug I'm talking about.

Nick

Hi Nick,

ok, now I've been able to reproduce it. It's a bug, I've added it on our defect list and a fix for it will be considered to inclusion in one of the next maintenance releases.
In meantime the better way would be to use the workaround you've found.

Thanks for the advise !