Shadow not showing when background color is clear color

Question

I've created an uiview in my xib with background color as clear color. When I apply the shadow on the layer of the view, the shadow is not appearing. But when i set the background color other than clear color, shadow is showing. Please help.

this is my code

self.cView.layer.shadowColor=[UIColor whiteColor].CGColor;
self.cView.layer.shadowOffset=CGSizeZero;
self.cView.layer.shadowRadius=30.0;
self.cView.layer.shadowOpacity=1.0;
self.cView.layer.cornerRadius=10.0;

Answer 1

The problem is, that shadow actually takes into account the 'upper' layer. If there's nothing on it there will be no shadow: How Shadows Work

EDIT:

There is this recipe copied from paste bin

view.layer.shadowColor = [UIColor colorWithWhite:.5 alpha:1].CGColor;
view.layer.shadowRadius = 4.0f;
view.layer.shadowPath = CGPathCreateWithRect(CGRectMake(0, 0, 50, 50), NULL);
view.layer.shadowOpacity = 1.0f;
view.layer.shadowOffset = CGSizeMake(1, 1);

But I doubt this will be of any use to you: the result is a view 'painted' with color of a shadow and a shadow around it.