- CAGradientLayer *gradient = [CAGradientLayer layer];
- gradient.frame = self.view.bounds;
- gradient.colors = [NSArray arrayWithObjects:(id)[[UIColor redColor] CGColor], (id)[[UIColor whiteColor] CGColor], nil nil];
- [self.view.layer insertSublayer:gradient atIndex:0];
来源: http://www.phpxs.com/code/1005517/