毛玻璃

// 创建imageview
UIImageView *imageview = [[UIImageView alloc]initWithFrame:self.view.bounds];
imageview.image = [UIImage imageNamed:@"home2"];
[self.view addSubview:imageview];

//添加毛玻璃效果
UIToolbar *toobar = [[UIToolbar alloc]init];
toobar.frame = imageview.bounds;
toobar.barStyle = UIBarStyleBlack;
[imageview addSubview:toobar];