Xcode6 自带毛玻璃效果

UIBlurEffect *blur = [UIBlurEffect effectWithStyle:UIBlurEffectStyleDark];

UIVisualEffectView *effectview = [[UIVisualEffectView alloc] initWithEffect:blur];

effectview.frame = CGRectMake(0,0, 320,320);

[self.view addSubview:effectview];