I'm using a UIScrollView to programatically animate some content.
However, I need to slow down the scrolling of the view.
This is the code I am using for the scrolling:
self.scrollView.setContentOffset(CGPoint(x: 0, y: self.view.frame.height), animated: true)
I have tried to add scrollView.decelerationRate = UIScrollViewDecelerationRateFast but it didn't seem to be working.
Try the following code:
UIView.animate(withDuration: 1.5) {
self.scrollView.contentOffset = CGPoint(x: 0, y: self.view.frame.height)
}
Related
I'm implementing a subview but I need to change the subview high programmatically but. This is how I'm changing the high:
func changeHigh() {
UIView.animate(withDuration: 1.0, animations: {
self.frame = CGRect(x: 0, y: 0, width: self.frame.width, height: self.frame.height - 50)
self.buttonConstraint.constant = 10
})
}
But the problem with this implementation is animating also the position of the view. All I want is to change the high with out changing the position.
Any of you knows why is changing the position of the subview?
I'll really appreciate you help.
First, to change the height, you can just modify the size.height property of the frame.
self.frame.size.height -= 50 /// this will make it 50 pts less
Also, you should change constraints outside the animation block, not inside. Then, call layoutIfNeeded() to animate it.
Here's how your code should look:
func changeHigh() {
self.buttonConstraint.constant = 10
UIView.animate(withDuration: 1.0, animations: {
self.frame.size.height -= 50
self.layoutIfNeeded()
})
}
I have an app that has a fullscreen PDFView, and I'm trying to add an animatable tab bar on the top of the screen. However, any time I animate the PDFView's frame to show the tab bar, the PDF loaded in the view jumps to another position.
I've tried to animate with UIView.animate and with UIViewPropertyAnimator, and adding the PDFView as a subview and animating the parent, but all result in the same problem.
Has anyone encountered this problem? Any ideas on how to create the animation in a way that would result in a smooth user experience? The tab bar could obviously animate itself on top of the PDFView, but I don't like the idea of it covering the PDF.
Thanks!
func CreatePDFView() {
pdfView.frame = CGRect(x: 0, y: 0, width: UIScreen.main.bounds.width, height: UIScreen.main.bounds.height)
view.addSubview(pdfView)
}
func AnimatePDFView() {
UIView.animate(withDuration: 1) {
self.pdfView.frame = CGRect(x: 0, y: 40, width: UIScreen.main.bounds.width, height: UIScreen.main.bounds.height - 40)
}
}
I've been looking to add this functionality for months, but haven't been able to solve this. As soon as I asked this question, though, it seems that I did.
You need to animate pdfView.documentView?.frame, and compensate for the current frame. I did this with UIEdgeInsets, and it seems to work.
if tabDocumentBrowserIsVisible {
tabDocumentBrowser.Animate(toState: .hidden)
UIView.animate(withDuration: 0.3) {
let inset = UIEdgeInsets(top: -80, left: 0, bottom: 0, right: 0)
self.pdfView.documentView?.frame = self.pdfView.documentView?.frame.inset(by: inset) as! CGRect
}
tabDocumentBrowserIsVisible = false
} else {
tabDocumentBrowser.Animate(toState: .visible)
UIView.animate(withDuration: 0.3) {
let inset = UIEdgeInsets(top: 80, left: 0, bottom: 0, right: 0)
self.pdfView.documentView?.frame = self.pdfView.documentView?.frame.inset(by: inset) as! CGRect
}
tabDocumentBrowserIsVisible = true
}
The PDF still behaves a bit funny if you are scrolling it while you animate it, but it's not too bad.
Im made and DropDown Menu to select Action like the GIF below.
Therefore I made a Subview and animated it in.
When animating the Subview out, it looks really weird.
In particular the problem is that it just looks like a blank small bar and not like the Menu.
Does anyone know where the problem might be?
The ViewController I'm making the Subview of is a simple ViewController with a TableView inside and 1 prototype cell.
Code:
let blackView = UIView()
var tvx: OptionsVC = OptionsVC()
var h: CGFloat!
.
func optionsClicked() {
self.h = CGFloat(70 + (52 * (OptionsVC().arrayFunctionCellNames.count)))
navigationController?.hidesBarsOnTap = false
tvx = self.storyboard?.instantiateViewController(withIdentifier: "options") as! OptionsVC
if let window = UIApplication.shared.keyWindow {
blackView.backgroundColor = UIColor(white: 0, alpha: 0.5)
blackView.addGestureRecognizer(UITapGestureRecognizer(target: self, action: #selector(handleDismiss)))
view.addSubview(blackView)
view.addSubview(tvx.view)
let y = (self.navigationController?.navigationBar.frame.size.height)! + UIApplication.shared.statusBarFrame.height
tvx.view.frame = CGRect(x: 0, y: (y - self.h), width: view.frame.width, height: h)
blackView.frame = CGRect(x: 0, y: y, width: view.frame.width, height: view.frame.height)
blackView.alpha = 0
UIView.animate(withDuration: 0.5, delay: 0, usingSpringWithDamping: 1, initialSpringVelocity: 1, options: .curveEaseOut, animations: {
self.blackView.alpha = 1
self.tvx.view.frame = CGRect(x: 0, y: y, width: self.view.frame.width, height: self.h)
self.blackView.frame = CGRect(x: 0, y: (y + self.h), width: self.view.frame.width, height: self.view.frame.height)
}, completion: nil)
}
}
.
func handleDismiss() {
UIView.animate(withDuration: 5.5, animations: {
let y = (self.navigationController?.navigationBar.frame.size.height)! + UIApplication.shared.statusBarFrame.height
self.blackView.alpha = 0
if let window = UIApplication.shared.keyWindow {
self.blackView.frame = CGRect(x: 0, y: y, width: self.view.frame.width, height: self.view.frame.height)
self.tvx.view.frame = CGRect(x: 0, y: (y - self.h), width: self.view.frame.width, height: self.h)
}
}, completion: {(finished:Bool) in
self.blackView.removeFromSuperview()
self.tvx.view.removeFromSuperview()
self.navigationController?.hidesBarsOnTap = true
})
}
GIF of BUG:
I made it so slow so you can better see it
Edit: My Solution
The problem was the constraints I set on my subview controller. Normally you set them to all sides, in my case, with was really weird I had to set them only to the bottom and sides. If I set some to the top, it would always do this bug.
You haven't really provided enough information for us to understand what's going on. What are tvx, blackView and self? What is the self.h variable? (From the animation it looks like you're changing the height of your "menu" view to be much shorter before you begin the animation code.)
Do you have a view controller contained inside another one using an embed segue?
If so, you should probably animate the constraints on the container view, not the child view controller's view.
As Glenn and D. Greg say in their comments, you should really be adding constraints to your views, hooking up outlets to those constraints, and animating changes to the constraint's constants rather than manipulating your view's frames directly. Animating changes to your view's frames isn't reliable when you're using AutoLayout, since AutoLayout can change your view's size and position out from under your animation code. That code looks like this, (in broad terms, no specific to your code)
myViewAConstraint.constant = someNewValue
myViewBConstraint.constant = someOtherValue
UIView.animate(withDuration: 5.5,
animations: {
someView.alpha = 0 //If you want the view to fade as it animates
self.view.layoutIfNeeded()
},
completion: { (finished:Bool) in
}
)
Is there a way to animate an object in swift (UIView, UIButton, etc.) so that it slides out on the left side of the screen and slides in at the same time on the right side of the screen, that the parts of f.e. an UIView that already slided out on the left side are already sliding in again from the right side.
I hope you can understand my question, its a bit tricky to explain this problem.
I'm using Xcode + Swift 3.0.
Thank you.
that the parts of f.e. an UIView that already slided out on the left side are already sliding in again from the right side
This almost slipped by me. The only way you have one "view" appear in two places on a screen is by really having two views, one on the left and one on the right.
Then, you could set the widthAnchors (properly), hide the subviews (properly), and animate. If the animation is fast enough (my one-sided slide out is set for 0.3 seconds) the user would think it's all one view.
You can use UIView.animate(). Trigger a second animation after the first has completed.
Possible implementation to get the idea:
var container = UIView(frame: CGRect(x: 0.0, y: 0.0, width: 200.0, height: 200.0))
let view = UIView(frame: CGRect(x: 0.0, y: 0.0, width: 50.0, height: 50.0))
view.center = CGPoint(x: 100, y: 100)
view.backgroundColor = UIColor.green
container.addSubview(view)
let screenWidth = CGFloat(356.0)
// animate to left
UIView.animate(withDuration: 2.0, delay: 0.0, options: [], animations: {
view.center = CGPoint(x: -view.frame.size.width, y: view.frame.origin.y)
}, completion: { (finished: Bool) in
//set view to right of screen
view.center = CGPoint(x: view.frame.size.width + screenWidth, y: view.frame.origin.y)
// animate back to center
UIView.animate(withDuration: 2.0, delay: 0.0, options: [], animations: {
view.center = CGPoint(x: 100, y: 100)
})
})
I am totally aware that you cannot push the same UIViewController from a UINavigationController. However my implementation demands so. I have to swipe gestures. On swiping right to left, I have to reload the content of view (which is a UIScrollView) along with animation. And vice versa on left to right swipe.
I have tried with following but it does not give the expected animation:
func leftSwipe()
{
self.scroll_course_detail.frame = CGRect(x: 2*self.scroll_course_detail!.frame.size.width, y: self.scroll_course_detail.frame.origin.y, width: self.scroll_course_detail.frame.size.width, height: self.scroll_course_detail.frame.size.height)
UIView.animate(withDuration: 0.25, animations: {() -> Void in
self.scroll_course_detail.frame = CGRect(x: 0, y: self.scroll_course_detail.frame.origin.y, width: self.scroll_course_detail.frame.size.width, height: self.scroll_course_detail.frame.size.height)
})
}
func rightSwipe()
{
self.scroll_course_detail.frame = CGRect(x: -self.scroll_course_detail!.frame.size.width, y: self.scroll_course_detail.frame.origin.y, width: self.scroll_course_detail.frame.size.width, height: self.scroll_course_detail.frame.size.height)
UIView.animate(withDuration: 0.25, animations: {() -> Void in
self.scroll_course_detail.frame = CGRect(x: 0, y: self.scroll_course_detail.frame.origin.y, width: self.scroll_course_detail.frame.size.width, height: self.scroll_course_detail.frame.size.height)
})
}
Before animation block, I am changing the frame of UIScrollView which makes the background clear for the animation duration. I was thinking that UIScrollView content is overriden along with animation
So what should be the best approach for reloading content along with animation on swipe ?