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All series points on FastLine disappearing

Posted: Tue Nov 24, 2009 10:58 pm
by 13052841
Hello, I am seeing a weird issue with the FastLine. Every so often, all of the x and y points will disppear from the series (fastLine1.XValues.Count == 0) for a very brief moment in time and then right after this all of the points will be there again.

When I watch the XValues.Count using a timer, I basically see:
# XValues
200
200
200
200
0
200
200
...

My program design is as follows:

A backgroundWorker reads data in a while loop over a network connection and saves this data in a List
A second backgroundWorker makes a local copy of the newest data from this List, parses it and adds it to a DataTable.

A Windows Forms timer then periodically refreshes the graph using the following function:

Code: Select all

        private void RefreshGraph()
        {
            for (int i = 0; i < tChartWeldTelem.Series.Count; i++)
            {
                try
                {
                    tChartWeldTelem[i].CheckDataSource();
                }
                catch { }
            }
        }
As mentioned, the FastLine has this behaviour periodically and nothing in my code is resetting or .Clear-ing the fastLine.

Has anyone experienced anything similar to this?

Re: All series points on FastLine disappearing

Posted: Wed Nov 25, 2009 7:48 am
by narcis
Hi LibDundas,

Which is the exact TeeChart version are you using? Have you tried using most recent version available at the client area? If the problem persists can you please attach a simple example project with which we can reproduce the issue here?

Thanks in advance.

Re: All series points on FastLine disappearing

Posted: Wed Nov 25, 2009 8:48 pm
by 13052841
Hi NarcĂ­s, thanks for the reply. I upgraded to the newest build of v4.0 and the problem still exists. I uploaded a stripped down version of my application to the Support Uploads page titled: "RealTime DataLogger Stripped-down Tchart 4.0.zip"

The app is fairly simple. Launch and click Start Logger. It will generate random points, add them to a DataTable, and then refresh the graph with the data points.

Watch the graph for a short while. The problem is that each line will flicker periodically at random intervals when the line itself contains ZERO points..even though the dataTable behind the line still contains a large number of points.

Please let me know if you have any questions about the test program. This bug is very important and is present in all of my applications using v3.5 and v4.0.

Thanks in advance!

Re: All series points on FastLine disappearing

Posted: Fri Nov 27, 2009 3:34 pm
by yeray
Hi LibDundas,

Thank you for the project. I can see how the chart flickers. I've taken a look over the code but I'm afraid the main problem doesn't look obvious to me. There are more than 1300 lines of code and it uses threads.
Could you please try to arrange a simple example project we can run as-is to reproduce the problem here and easily identify where the main problem could be?

Thanks in advance.

Re: All series points on FastLine disappearing

Posted: Fri Nov 27, 2009 4:05 pm
by 13052841
Hi Yeray, thanks for the reply. I will try to simplify the program further and let you know how it goes.