RenderTargetBitmap.Render() creates blank image when element present in Grid.Row = "1"

Question

Save element (inherited from System.Windows.Controls.Control) as image using below code.

RenderTargetBitmap bmpSource = new RenderTargetBitmap((int)element.ActualWidth, (int)element.ActualHeight, 96, 96, PixelFormats.Pbgra32);  
bmpSource.Render(element);  
imgEncoder.Frames.Add(BitmapFrame.Create(bmpSource));  
using (Stream stream = File.Create(fileName))  
{  
    imgEncoder.Save(stream);  
}  
  

Works fine when element present in 0 th row, not works for 1st row inside grid. By as a workaround, added inside the stackpanel and then grid it works.
80054-customcontrol.txt

[Xaml]

<Grid.RowDefinitions>  
                                <RowDefinition Height="auto"/>  
                                <RowDefinition Height="25*"/>  
                                <RowDefinition Height="75*"/>  
                            </Grid.RowDefinitions>  
. . .  
<local:CustomControl x:Name="StackingColumnChart2" Template="{StaticResource Template}" Grid.Row="1"/>   
. . .  
  
  

Answer 1

I update your Save method as below shown to implement want you want

 public void Save(string fileName)  
        {  
            FrameworkElement element = this;  
            string imageExtension;  
            imageExtension = new FileInfo(fileName).Extension.ToLower(System.Globalization.CultureInfo.InvariantCulture);  
            BitmapEncoder imgEncoder;  
            switch (imageExtension)  
            {  
                case ".bmp":  
                    imgEncoder = new BmpBitmapEncoder();  
                    break;  
                case ".jpg":  
                case ".jpeg":  
                    imgEncoder = new JpegBitmapEncoder();  
                    break;  
                case ".png":  
                    imgEncoder = new PngBitmapEncoder();  
                    break;  
                case ".gif":  
                    imgEncoder = new GifBitmapEncoder();  
                    break;  
                case ".tif":  
                case ".tiff":  
                    imgEncoder = new TiffBitmapEncoder();  
                    break;  
                case ".wdp":  
                    imgEncoder = new WmpBitmapEncoder();  
                    break;  
                default:  
                    imgEncoder = new BmpBitmapEncoder();  
                    break;  
            }  
            if (element != null)  
            {  
                DrawingVisual drawingVisual = new DrawingVisual();  
                using (DrawingContext context = drawingVisual.RenderOpen())  
                {  
                    VisualBrush brush = new VisualBrush(element) { Stretch = Stretch.Fill };  
                    context.DrawRectangle(brush, null, new Rect(0, 0, element.ActualWidth, element.ActualHeight));  
                    context.Close();  
                }  
  
                RenderTargetBitmap bitmap = new RenderTargetBitmap((int)element.ActualWidth, (int)element.ActualHeight, 96, 96, PixelFormats.Pbgra32);  
                bitmap.Render(drawingVisual);  
  
                imgEncoder.Frames.Add(BitmapFrame.Create(bitmap));  
                using (Stream stream = File.Create(fileName))  
                {  
                    imgEncoder.Save(stream);  
                }  
            }  
        }  
   

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