backgroundColor property
final
The background color of the surface of this Dialog.
This sets the Material.color on this Dialog's Material.
If null, then the DialogThemeData.backgroundColor is used. If that is also null, defaults to ColorScheme.surfaceContainerHigh. If ThemeData.useMaterial3 is false, defaults to Colors.grey with a shade of 800 in dark theme and Colors.white in light theme.
If Dialog.fullscreen is used, defaults to ColorScheme.surface.
Implementation
final Color? backgroundColor;