在 UIVisualEffectView 的底部添加淡入淡出

如何解决在 UIVisualEffectView 的底部添加淡入淡出

大家好，我试图让我的模糊视图消失，而不是突然切到墙纸。我是新来的，并且很高兴让它更像我自己。

我最终想要的效果

关于我想要实现的目标的另一个例子

到目前为止我得到了什么

self.diaryPlayerView = [UIView new];
self.MediaPlayerblurEffect = [UIBlurEffect effectWithStyle:UIBlurEffectStyleSystemUltraThinMaterialDark];
self.MediaPlayerEffectView = [[UIVisualEffectView alloc] initWithEffect:[self MediaPlayerblurEffect]];
self.MediaPlayerEffectView.alpha = 1;
[[self diaryPlayerView] setHidden:YES];
[[self MediaPlayerEffectView] setHidden:YES];
[self addSubview:[self MediaPlayerEffectView]];
[self addSubview:[self diaryPlayerView]];

[[self diaryPlayerView] setTranslatesAutoresizingMaskIntoConstraints:NO];
[NSLayoutConstraint activateConstraints:@[
    [self.diaryPlayerView.topAnchor constraintEqualToAnchor:self.topAnchor],[self.diaryPlayerView.leadingAnchor constraintEqualToAnchor:self.leadingAnchor],[self.diaryPlayerView.trailingAnchor constraintEqualToAnchor:self.trailingAnchor],[self.diaryPlayerView.heightAnchor constraintEqualToConstant:140 + [mediaPlayerOffsetValue doubleValue]],]];

[[self MediaPlayerEffectView] setTranslatesAutoresizingMaskIntoConstraints:NO];
[NSLayoutConstraint activateConstraints:@[
    [self.MediaPlayerEffectView.topAnchor constraintEqualToAnchor:self.diaryPlayerView.topAnchor],[self.MediaPlayerEffectView.leadingAnchor constraintEqualToAnchor:self.diaryPlayerView.leadingAnchor],[self.MediaPlayerEffectView.trailingAnchor constraintEqualToAnchor:self.diaryPlayerView.trailingAnchor],[self.MediaPlayerEffectView.heightAnchor constraintEqualToConstant:140 + [mediaPlayerOffsetValue doubleValue]],]];