Using CALayers for dynamic shadows

gistfile1.m

UIView *myView = [[UIView alloc] initWithFrame:CGRectMake(30, 30, 260, 260)]; 

/* It's important to remember to pass CG structs like floats and CGColors */
[[myView layer] setShadowOffset:CGSizeMake(0, 1)];
[[myView layer] setShadowColor:[[UIColor darkGrayColor] CGColor]];
[[myView layer] setShadowRadius:3.0];