Web chart into a datalist

tenaris · Post by **tenaris** » Fri Aug 10, 2007 2:23 pm

Hello, we are working with an asp.net 2.0 web form which contains a Datalist with a WebChart (Version=2.0.2670.26521) inside the items template. When I run the page the chart sometimes repeats the code generated for the different items in the datalist. For that reason some chart images doesn’t appear in the page, and other ones does appear repeated.
I’m using the DataList’s OnItemDataBound event in order to fill the chart series and I’m using the Session option for chart streaming.
I made the following test: I inserted a delay in the chart’s AfterDraw event and it work better, but I don't know why.
Could you help us with with this problem?
Thanks

Narcís · Post by **Narcís** » Fri Aug 10, 2007 2:30 pm

Hi tenaris,

Your problem could be something similar to what was discussed on this thread. A solution could be asynchronous repaint technique using TeeChart's AutoRepaint property.

Hope this helps!

tenaris · Post by **tenaris** » Fri Aug 10, 2007 4:59 pm

I read the thread but my problem is different.
I'll try to explain it in a different way.
Suppose you bind a datalist to a dataset with three rows. For each row you do a subquery to fill a chart with different points.
When you execute the web form you will receive something like the following code. If you pay attention, the third row is wrong. I don’t know why the Webchart repeats the third number instead of to generate a new one. This behavior is random, for that reason I try with a delay. This is not a multithreading problem, the execution is sequential.

<table id="ctl00_Contents_TurnoList" >
<tr>
<td>
<IMG SRC="GetChart.aspx?Chart=GanttChart127001393045836934954" id="GanttChart" Name="GanttChart">
</td>
</tr>
<tr>
<td>
<IMG SRC="GetChart.aspx?Chart=GanttChart127001393045671627199" id="GanttChart" Name="GanttChart">
</td>
</tr>
<tr>
<td>
<IMG SRC="GetChart.aspx?Chart=GanttChart127001393045671627199" id="GanttChart" Name="GanttChart">
</td>
</tr>
</table>

Regards

Narcís · Post by **Narcís** » Mon Aug 13, 2007 7:19 am

Hi tenaris,

Thanks for the information. Would you be so kind to arrange a simple example project we can run "as-is" to reproduce the problem here?

For the example you can try manually creating datasets as shown in the example Christopher Ireland posted here.

Files can be posted at news://www.steema.net/steema.public.attachments newsgroup or at our upload page.

Thanks in advance.

tenaris · Post by **tenaris** » Mon Aug 13, 2007 6:26 pm

Hello, i made a sample project named "TestChart" with these problem and i submit it at your upload page. Please tell me if you could not receive it. Use the refresh button to check the sample.

Narcís · Post by **Narcís** » Tue Aug 14, 2007 11:22 am

Hi tenaris,

Thank you very much for the example. We have been able to reproduce the problem here and have enhanced the unique name generation for the chart files. I've sent you a debug version of TeeChart.dll. Would you be so kind to test it at your end and let us know if this solution is acceptable for you?

Thanks in advance.

tenaris · Post by **tenaris** » Tue Aug 14, 2007 2:49 pm

Hi Narcis, thanks for your help
I did the same test that i sent you yesterday with the new dll the and the problem is still there. Is the version ok? the new dll's version is previous than the last version available.
Regards

Narcís · Post by **Narcís** » Tue Aug 14, 2007 3:01 pm

Hi tenaris,

Thanks for the information. Yes, the assembly I sent you is correct, it is a debug build and the build number is not significative.

Could you please check that your project reference to TeeChart.dll has been updated? To be 100% sure of that you could run your application, right-click on the page and select "View Source", check that file names have 33 digit names.

If all this is correct and the problem persists, would you be so kind to let us know the exact test you did so that we can reproduce the problem here?

Thanks in advance.

tenaris · Post by **tenaris** » Tue Aug 14, 2007 3:13 pm

Hi, I've checked the reference and it is ok
The last run of the sample page genereted the following code.
The third or fourth item is wrong.
Regards.

<table id="ChartList" cellspacing="0" border="0" style="border-collapse:collapse;">
<tr>
<td>
<span id="ChartList_ctl00_ItemTitle">Item 0 - Start Date 1/1/2007 12:00:00 AM</span><br/>
<IMG SRC="GetChart.aspx?Chart=GanttChart1270011465650043633226901983791708" id="GanttChart" Name="GanttChart" style="height:35px; width:800px;" Border=0>
</td>
</tr><tr>
<td>
<span id="ChartList_ctl01_ItemTitle">Item 1 - Start Date 1/1/2007 6:00:00 AM</span><br/>
<IMG SRC="GetChart.aspx?Chart=GanttChart127001814609723633226901985041812" id="GanttChart" Name="GanttChart" style="height:35px; width:800px;" Border=0>
</td>
</tr><tr>
<td>
<span id="ChartList_ctl02_ItemTitle">Item 2 - Start Date 1/1/2007 12:00:00 PM</span><br/>
<IMG SRC="GetChart.aspx?Chart=GanttChart12700144081795633226901985198075" id="GanttChart" Name="GanttChart" style="height:35px; width:800px;" Border=0>
</td>
</tr><tr>
<td>
<span id="ChartList_ctl03_ItemTitle">Item 3 - Start Date 1/1/2007 6:00:00 PM</span><br/>
<IMG SRC="GetChart.aspx?Chart=GanttChart12700144081795633226901985198075" id="GanttChart" Name="GanttChart" style="height:35px; width:800px;" Border=0>
</td>
</tr><tr>
<td>
<span id="ChartList_ctl04_ItemTitle">Item 4 - Start Date 1/2/2007 12:00:00 AM</span><br/>
<IMG SRC="GetChart.aspx?Chart=GanttChart127001395453686633226901985354338" id="GanttChart" Name="GanttChart" style="height:35px; width:800px;" Border=0>
</td>
</tr>
</table>

Narcís · Post by **Narcís** » Thu Aug 16, 2007 3:59 pm

Hi tenaris,

We haven't been able to reproduce the problem here. However, we added an enhancement on how the unique ID is created so that it avoids repetition. I've sent you a new debug version of TeeChart.dll. Would you be so kind to let us know how it goes at your end?

Thanks in advance!

tenaris · Post by **tenaris** » Thu Aug 16, 2007 8:36 pm

Thank you very much Narcis, this time it works.
Will you include this enhancement in the next maintenance release?
Best Regards

Narcís · Post by **Narcís** » Fri Aug 17, 2007 8:42 am

Hi tenaris,

You're very welcome. I'm glad to hear that works now. Yes, we will include this change in the next v2 and v3 releases.