Gets the background color of a component.
You can have both a backgroundColor and a backgroundImage set. Some components do not have a background. The DataGrid control ignores this style. The default value is undefined, which means it is not set. If both this style and the backgroundImage style are undefined, the component has a transparent background.
For the Application container, this style specifies the background color while the application loads, and a background gradient while it is running. Flex calculates the gradient pattern between a color slightly darker than the specified color, and a color slightly lighter than the specified color.
The default skins of most Flex controls are partially transparent. As a result, the background color of a container partially shows through to controls that are in that container. You can avoid this by setting the alpha values of the control's fillAlphas property to 1.