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We have prepared sample to customize the color of Animation by using Foreground property. Please find the sample from below attachment .
Please let us know if the above sample meets your requirements or not. If not please provide more information like image file of your expected customization in SfBusyIndicator.
Sorry for the inconvenience.
We have prepared a sample to apply gray shadow effect for entire window by changing the window background as gray and also modified the controls opacity which is in the window. Please find the sample from the attached file.
Please let us know whether the below sample meets your requirement or not. If not please provide more details which will help to provide appropriate solution.
In fact ,I think this should be the default feature of SfBusyIndicator.Beause when you loading data,you just barely see the text on busyindicator.