Starting a actionscript project with width and height set

When using Flex for a Actionscript project development, I always run into a situation that the testing movie doesn't have a prefered size, even I set the mc.width and mc.height in the script.

The following is the solution:

package
{
import flash.display.MovieClip;

[SWF(width="1000", height="628", backgroundColor="0x000000", frameRate="30")]
public class SampleMovieClip extends MovieClip
{
}
}