ThemeData.primaryColor is currently the default background color for AppBar. Apps should configure the default background color for AppBar's with AppBar.color, AppBarTheme.backgroundColor, or the theme's ColorScheme.primaryColor.

Support for ThemeData.primaryColor is being phased out because it's redundant with ColorScheme.primary and not as clear as AppBar.color or AppBarTheme.backgroundColor.

Support for ThemeData.primaryColor, when it's not the same as the ColorScheme's primary, has been temporarily enabled for AppBar in ... until old applications have had a chance to update.