Problem exporting databound chart that isn't visible

[David Brubacher]

As part of my application I am storing some meta-data on the server. That meta-data needs to contain a chart.
I have a user control that contains all of the logic of the chart, which the user can see at any time just by clicking a button.

I'm trying to generate the same chart and export it to a PNG even if the chart isn't visible

        /// <summary>
        /// Send a chart image when asked
        /// </summary>
        public byte[] MakeChartImage()
        {
            chart.Arrange(new Rect(new Point(0, 0), new Size(1024, 768)));
            var stream = new MemoryStream();
            chart.ExportToImage(stream, new PngBitmapEncoder());
            return stream.ToArray();
        }

I'm using MEF and MVVM, so the cart gets a message that there is new chart data, does a Rebind, then
raises an event to let the calling app know its safe to call the above method.

The chart I get is devoid of all bound data (see attachment).
How do you force the chart to render despite it not being visible?
I've also included a chart as it looks when the user views it.

[David Brubacher]

This is what the chart should look like (minus the radwindow)

[David Brubacher]

Some progress.

Here is where I generate the meta-data in a view model

        /// <summary>
        /// Report metadata back to the server on what we are querying
        /// </summary>
        /// <param name="ignore">This value isn't used</param>
        private void GenerateData(string ignore)
        {
            var chart = new ChartView();
            chart.DataBound += ChartDataBound;
            _ChartWindow = new RadWindow
                               {
                                   Left = -2000,
                                   Top = -2000,
                                   Width = 1100,
                                   Height = 850,
                                   Content = chart
                               };
            _ChartWindow.Show();
            SendDataToChart(false);
        }
 
        private void ChartDataBound(object sender, EventArgs e)
        {
            var chart = sender as ChartView;
            if (chart == null)
            {
                _ChartWindow.Close();
                return;
            }
            var usage = new Usage
            {
                ...,
                Chart = chart.MakeChartImage(),
                ...,
            };
            _ChartWindow.Close();
            _Model.SubmitUsage(usage);
        }


and here is the MakeChartImage() method
        /// <summary>
        /// Send a chart image when asked
        /// </summary>
        public byte[] MakeChartImage()
        {
            chart.UpdateLayout();
            var stream = new MemoryStream();
            chart.ExportToImage(stream, new PngBitmapEncoder());
            return stream.ToArray();
        }
The some data it binding but not the bubbles

[Bartholomeo Rocca]

Hello David,

Try disabling the chart animations (RadChart.DefaultView.ChartArea.EnableAnimations = false) prior to exporting the image and you should be able to achieve the desired effect.


Greetings,
Bart.

[David Brubacher]

No change unfortunately. Thanks for the suggestion though.

[Yavor]

Hello David,

Based on the supplied information, it is hard to determine what is causing this unwanted behavior. If the issue persists, you can open a formal support ticket, and send us a small working project, demonstrating your implementation, and showing the unwanted behavior. We will review it locally, and advise you further.

All the best,
Yavor
the Telerik team

[David Brubacher]

Sorry for not supplying additional info - circumstances took me away from this project for a while.
I've returned to it today, applied the new service pack and voila! everything works as expected.

Thnk-you very much!

[Yavor]

Hi David,

I am glad that the issue has been resolved, and that the project is working as per your requirements now.
If further questions/issues arise, let us know.

Regards,
Yavor
the Telerik team