Programmatically scroll a UIScrollView to the top of a child UIView (subview) in Swift

Question

I have a few screens worth of content within my UIScrollView which only scrolls vertically.

I want to programmatically scroll to a view contained somewhere in it\'s

Answer 1

 scrollView.scrollRectToVisible(CGRect(x: x, y: y, width: 1, height:
1), animated: true)

or

scrollView.setContentOffset(CGPoint(x: x, y: y), animated: true)

Another way is

scrollView.contentOffset = CGPointMake(x,y);

and i do it with animated like this

[UIView animateWithDuration:2.0f delay:0 options:UIViewAnimationOptionCurveLinear animations:^{
scrollView.contentOffset = CGPointMake(x, y); }
completion:NULL];

Answer 2

For scroll to top or bottom with completion of the animation

// MARK: - UIScrollView extensions

extension UIScrollView {
    /// Animate scroll to bottom with completion
    ///
    /// - Parameters:
    ///   - duration:   TimeInterval
    ///   - completion: Completion block
    func animateScrollToBottom(withDuration duration:  TimeInterval,
                            completion:             (()->())? = nil) {

        UIView.animate(withDuration: duration, animations: { [weak self] in
            self?.setContentOffset(CGPoint.zero, animated: false)
            }, completion: { finish in
                if finish { completion?() }
        })
    }

    /// Animate scroll to top with completion
    ///
    /// - Parameters:
    ///   - duration:   TimeInterval
    ///   - completion: Completion block
    func animateScrollToBottomTop(withDuration duration:  TimeInterval,
                                  completion:             (()->())? = nil) {
        UIView.animate(withDuration: duration, animations: { [weak self] in
            guard let `self` = self else {
                return
            }
            let desiredOffset = CGPoint(x: 0, y: -self.contentInset.top)
            self.setContentOffset(desiredOffset, animated: false)

            }, completion: { finish in
                if finish { completion?() }
        })
    }
}

Answer 3

scrollView.setContentOffset(CGPoint, animated: Bool)

Where the point's y coordinate is the y coordinate of the frame of the view you want to show relatively to the scrollView's content view.

Answer 4

Here is my answer, this is in swift. This will scroll the pages in scrollview infinitely.

private func startBannerSlideShow()
{
UIView.animate(withDuration: 6, delay: 0.1, options: .allowUserInteraction, animations: {
    scrollviewOutlt.contentOffset.x = (scrollviewOutlt.contentOffset.x == scrollviewOutlt.bounds.width*2) ? 0 : scrollviewOutlt.contentOffset.x+scrollviewOutlt.bounds.width
}, completion: { (status) in
    self.startBannerSlideShow()
})
}

Answer 5

For me, the thing was the navigation bar which overlapped the small portion of the scrollView content. So I've made 2 things:

• Size Inspector - Scroll View - Content Insets --> Change from Automatic to Never.
• Size Inspector - Constraints- "Align Top to" (Top Alignment Constraints)- Second item --> Change from Superview.Top to Safe Area.Top and the value(constant field) set to 0

Answer 6

For me scrollRectToVisible() didn't work (see here), so I used setContentOffset() and calculated it myself, based on AMAN77's answer:

extension UIScrollView {

    func scrollToView(view:UIView, animated: Bool) {
        if let superview = view.superview {
            let child = superview.convert(view.frame, to: self)
            let visible = CGRect(origin: contentOffset, size: visibleSize)
            let newOffsetY = child.minY < visible.minY ? child.minY : child.maxY > visible.maxY ? child.maxY - visible.height : nil
            if let y = newOffsetY {
                setContentOffset(CGPoint(x:0, y: y), animated: animated)
            }
        }
    }

}

It is for a horizontal scroll view, but the same idea can be applied vertically too.