Chart not updating data changes in PowerPoint

Question

Dear Experts,

I am facing problems updating data in a chart.

What I am trying to achieve is the following: A chart is inserted into the presentation at design time. Then, when the slideshow is run, the data (numbers) of the chart need to be updated from csharp code (with some real-time measurements).

I am using Chart.SeriesCollection to update the data. Althought the figures are set correctly in the object model, is not updated on screen, but the columns in the chart disappear.

When I stop the slideshow and user the functions "Edit data..." (in the context menu of the chart) or "Select data" (in the ribbon) suddenly tha figures I have set are updated in the chart, and all is displayed correctly. As a "side-effect" these buttons will also display Excel to show the data entry for the charts.

Also, if I call Chart.ChartData.Activate() during the slideshow, Excel is opened with the (original) chart data, and the correct figures are shown in the chart. Obviously this is not a viable solution, as the Excel window is appearing during the slideshow, which is definitely a no-go.

I also tried using Chart.Refresh() but it does not seems to have any effect. Chart data is only updated when the associated Excelsheet is show.

Did any of you manage to update data in a Chart in Powerpoint "silently"?

Thanks,

Oliver

Answer 1

Hi Oliver

I've moved your question to the General Office Developer forum, as that's where PowerPoint questions are discussed on MSDN. However, most of the PowerPoint specialists (even the programmers) "live" in the Answers forums. We can't move or copy questions to that set of forums, so you might want to post there, as well.

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Cindy Meister, VSTO/Word MVP

Answer 2

I have been able to update embeded Excel charts on slides while they are in a presentation window. However, this was done from another Excel file (on a second monitor). I will have to test it under the conditions you have.

Where is the C# code running? Is it being referenced as a class from within PowerPoint?

Answer 3

I have the same problem - looks like a bug

Has anyone found a workaround?

In the VBA code below I have 2 arrays of variants of size nPoints + 1: values and xvalues.  Target is the chart object

    target.SetSourceData "='Sheet1'!$A$1:$B$" & CStr(nPoints + 1)
    target.SeriesCollection(1).xvalues = xvalues
    target.SeriesCollection(1).values = values

Nothing updates unless I edit the data

Answer 4

My code is within a class which is called by the VSTO AddIn.

I have used the following workaround:

- During the start of the slideshow open excel

- Either change the excel application to invisible or just minimize/deactivate the window

Is not a perfect solution but the best one I could come up with.

Answer 5

Hi Sviver

Thanks for taking a moment to come back and outline your workaround :-)

As I was reading through your original message again, it occurred to me that another possible work-around would be to link the chart in from Excel. It's possible, if you maintain the complete chart + data in Excel that it would render correctly when PowerPoint loads it. Might be worth a quick test if having to run the Excel application parallel to PowerPoint is undesirable.

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Cindy Meister, VSTO/Word MVP