Copying 3D graph to clipboard does not copy axis labels

[Martijn]

I use a RadCartesianChart3D for displaying a 3D graph. For copying this graph to Clipboard, I render the view model again and copy it to the Clipboard. But that copy does not contain the axis labels.

I use the following code to copy the view model to Clipboard:

            var data = new DataObject();

            var bitmap = RenderToBitmap(this);
            if (bitmap != null)
            {
                data.SetData(DataFormats.Bitmap, bitmap);
            }

            Clipboard.SetDataObject(data);

And RenderToBitmap is as follows:

        public BitmapSource RenderToBitmap(object viewModel, double dpi = 300.0)
        {
            var element = new Border()
            {
                Child = new ContentControl()
                {
                    Content = viewModel,
                },
                Background = new SolidColorBrush(Colors.White),
            };

            element.Measure(new Size(double.PositiveInfinity, double.PositiveInfinity));
            element.Arrange(new Rect(element.DesiredSize));
            element.InvalidateVisual();
            element.UpdateLayout();

            var target = new RenderTargetBitmap((int)(element.ActualWidth * dpi / 96.0), (int)(element.ActualHeight * dpi / 96.0), dpi, dpi, PixelFormats.Default);

            target.Render(element);

            return BitmapFrame.Create(target);
        }

 

Why is the copy not containing the axis labels?

[Martin Ivanov]

Hello Martijn,

We are aware of this behavior. It happens because the chart needs to be placed and loaded in the visual tree, in order to render its axes. This means that you cannot export the chart to an image until you render it. One way to achieve your requirement is to show the chart in a hidden Window, export it and then hide the window. For example:

var w = new Window();
w.WindowStyle = WindowStyle.None;
w.Height = 0;
w.Width = 0;
w.Content = elementHostingTheChart;
w.Loaded += (s, e) =>
{
    using (Stream stream = new FileStream("../../test.png", FileMode.Create))
    {
        Telerik.Windows.Media.Imaging.ExportExtensions.ExportToImage(
            elementHostingTheChart, stream, new System.Windows.Media.Imaging.PngBitmapEncoder());
    }
    w.Close();
};
 
w.Show();

This approach is mentioned also here.

I hope that helps.

Regards,
Martin Ivanov
Progress Telerik

[Martijn]

Hello Martin,

 

That solves a big part from my problem. But then the saved picture looks as attached. What parts do I need to bind to the view model to make sure that it is saved as visible on the screen?

[Martin Ivanov]

You should ensure that the panel (that hosts the legend and the chart) you are exporting provides enough space (width and height) for the elements. I will guess that the layout shown in your first picture (graph-original.png) provides more width and height, than the layout that is passed to the export method. So, using bigger width and height for the measure should do the job. Also, you can try changing the Distance of the chart's camera behavior, so the chart appears farther away, thus smaller.

[Martijn]

Hello Martin,

 

Sorry for the late reply, but you were right. I changed width/height settings for the exported version and now it is displaying correctly!