几行代码实现图片的模糊效果
// 创建一个imageView
UIImageView * backImageView = [[UIImageView alloc]initWithFrame:self.view.bounds];
backImageView.image = [UIImage imageNamed:@"guidance03@3x.jpg"];
[self.view addSubview:backImageView];
//添加模糊效果
UIBlurEffect * blurEffect = [UIBlurEffect effectWithStyle:UIBlurEffectStyleLight];
UIVisualEffectView * effectView = [[UIVisualEffectView alloc]initWithEffect:blurEffect];
effectView.frame = CGRectMake(0, 64, self.view.frame.size.width, 300);
[backImageView addSubview:effectView];