滚动时对 TableViewCell 的模糊效果

Posted 2023-03-04

【中文标题】滚动时对 TableViewCell 的模糊效果

【英文标题】：Blur Effect on TableViewCell when scroll

【发布时间】：2015-06-10 22:44:41

【问题描述】：

现在我正在使用LBBlurredImage 来模糊图像，但我想改为ios8 的UIVisualEffectView 来模糊。

我很难实施，有什么想法吗？

用LBBLurredImage实现：

- (void)updateData 
    // Set up Screen
    self.screenHeight = [UIScreen mainScreen].bounds.size.height;
    //UIImage *background = [UIImage imageNamed:@"gray"];
    UIImage *background = [UIImage imageNamed:backgroundImageGlobal];

    // Background Image
    self.backgroundImageView = [[UIImageView alloc] initWithImage:background];
    self.backgroundImageView.contentMode = UIViewContentModeScaleAspectFill;
    [self.view addSubview:self.backgroundImageView];

    // Background Image Blurred
    self.blurredImageView = [[UIImageView alloc] init];
    self.blurredImageView.contentMode = UIViewContentModeScaleAspectFill;
    self.blurredImageView.alpha = 0.0; // 0.0
    [self.blurredImageView setImageToBlur:background blurRadius:10 completionBlock:nil]; // blurRadius:10
    [self.view addSubview:self.blurredImageView];


- (void)scrollViewDidScroll:(UIScrollView *)scrollView 
    CGFloat height = scrollView.bounds.size.height;
    CGFloat position = MAX(scrollView.contentOffset.y, 0.0);
    CGFloat percent = MIN(position / height, 1.0);
    self.blurredImageView.alpha = percent;

到目前为止，我在之前的代码中添加/更改的最好的镜头，使用UIVisualEffectView 实现：

// iOS8
@property (nonatomic) UIVisualEffect *blurEffect;
@property (nonatomic) UIVisualEffectView *visualEffectView;

// iOS8 Blur
self.blurredImageView = [[UIImageView alloc] init];
self.blurredImageView.contentMode = UIViewContentModeScaleAspectFill;
self.blurredImageView.alpha = 0.0;
UIBlurEffect *blurEffect = [UIBlurEffect effectWithStyle:UIBlurEffectStyleLight];
UIVisualEffectView *visualEffectView = [[UIVisualEffectView alloc] initWithEffect:blurEffect];
visualEffectView.frame = self.blurredImageView.bounds;
[self.blurredImageView addSubview:visualEffectView];
[self.view addSubview:self.blurredImageView];

【参考方案1】：

我想通了。我用过：

// iOS8 Blur
UIBlurEffect *blurEffect = [UIBlurEffect effectWithStyle:UIBlurEffectStyleLight];
self.visualEffectViewGlobal = [[UIVisualEffectView alloc] initWithEffect:blurEffect];
self.visualEffectViewGlobal.frame = self.view.bounds;
self.visualEffectViewGlobal.alpha = 0.0;
[self.view addSubview:self.visualEffectViewGlobal];