根据滚动视图位置移动 UILabel

Question

我的 headerView（图像视图）内有一个 titleLabel，它会根据滚动视图的滚动改变其大小。我正在尝试根据滚动视图的位置移动 titlelabel，因为它调整到与导航栏大致相同的大小我正在尝试将标签移动到反映导航标题的位置。这就是我目前正在尝试的方式。

    self.view.addSubview(self.imageView)
    self.imageView.translatesAutoresizingMaskIntoConstraints = false
    self.imageView.leadingAnchor.constraint(equalTo: self.view.leadingAnchor).isActive = true
    self.imageView.trailingAnchor.constraint(equalTo: self.view.trailingAnchor).isActive = true
    self.imageView.topAnchor.constraint(equalTo: self.view.topAnchor).isActive = true

    self.imageHeightConstraint = self.imageView.heightAnchor.constraint(equalToConstant: 400)
    self.imageHeightConstraint.isActive = true

    self.scrollView.delegate = self
    self.view.addSubview(self.scrollView)
    scrollView.anchor(top: imageView.bottomAnchor, left: view.leftAnchor, bottom: view.bottomAnchor, right: view.rightAnchor, paddingTop: -10, paddingLeft: 0, paddingBottom: 0, paddingRight: 0, width: 0, height: 0)

    self.scrollView.contentOffset = CGPoint(x: 0, y: -100)

ScrollViewDidScroll

func scrollViewDidScroll(_ scrollView: UIScrollView) {
    let y = 100 - (scrollView.contentOffset.y - 100)
    let height = max(y, 100)
    self.imageHeightConstraint.constant = height

    self.eventTitleLabel.center.y = scrollView.contentOffset.y 
}

Answer 1

您不仅需要更改 Y 值，还需要像这样更改所有框架

func scrollViewDidScroll(_ scrollView: UIScrollView) {
    let y = 100 - (scrollView.contentOffset.y - 100)
    let height = max(y, 100)
    self.imageHeightConstraint.constant = height

    //self.eventTitleLabel.center.y = scrollView.contentOffset.y 
    self.eventTitleLabel.frame = CGRect(x: 0, y: scrollView.contentOffset.y , width: label.frame.width, height: label.frame.height)

}

在这里，X 和 Y 管理你的 scrollview 作为你想要的位置。

根据滚动视图位置移动 UILabel

Move UILabel based on scrollview postion

uiscrollview

swift