Shrink heightConstraint animation issue - ios

I'm trying to make pull up menu view
I made this pull up view using xib and attached to ViewController
and added pan gesture on pull up view
lastly, I updated height constraint using pan gesture for animation.
func pullUpControlView(_ pullUpControlView: PullUpControlView, didPanned height: CGFloat, animated: Bool) {
self.pullUpControlViewHeightConstraint?.constant = height
if animated {
UIView.animate(withDuration: 10, delay: 0, usingSpringWithDamping: 0.7, initialSpringVelocity: 0, options: .curveEaseOut, animations: {
self.view.layoutIfNeeded()
}, completion: nil)
}
}
this is my code it's animation works fine when view got maximum height,
but when minimising view, view is minimised immediately and start move to down slowly (weird animation)
how can I make this animation correctly (shrink height from top to bottom)

func pullUpControlView(_ pullUpControlView: PullUpControlView, didPanned height: CGFloat, animated: Bool) {
UIView.animate(withDuration: 5, animations: {() -> Void in
self.view.layoutIfNeeded()
}, completion: {(_ finished: Bool) -> Void in
self.pullUpControlViewHeightConstraint?.constant = height
self.view.layoutIfNeeded()
//if animation is finished ("finished" == *YES*), then hidden = "finished" ... (aka hidden = *YES*)
})
}

Related

How to move UITableViewCell back and forth to show it can be swiped?

I see in some apps when you come to a screen with a tableview there's a short animation of the cell starting to be swiped, showing the red "swipe to delete" button (UIContextualAction button) and then it returns to normal. It is giving the user the hint: "These rows can be swiped."
Is there a way to achieve this effect? Maybe a way to programmatically start a row swipe then cancel it?
Swift Solution
Well, about 1.5 years later I finally came up with a solution.
Step 1 - Cell UI Setup
I set up my custom table view cell like this:
A and B represent the swipe action colors.
C is the UIView that I will animate side-to-side.
Step 2 - Add Animation to Cell
func animateSwipeHint() {
slideInFromRight()
}
private func slideInFromRight() {
UIView.animate(withDuration: 0.5, delay: 0.3, options: [.curveEaseOut], animations: {
self.cellBackgroundView.transform = CGAffineTransform(translationX: -self.swipeHintDistance, y: 0)
self.cellBackgroundView.layer.cornerRadius = 10
}) { (success) in
UIView.animate(withDuration: 0.2, delay: 0, options: [.curveLinear], animations: {
self.cellBackgroundView.transform = .identity
}, completion: { (success) in
// Slide from left if you have leading swipe actions
self.slideInFromLeft()
})
}
}
private func slideInFromLeft() {
UIView.animate(withDuration: 0.5, delay: 0, options: [.curveEaseOut], animations: {
self.cellBackgroundView.transform = CGAffineTransform(translationX: self.swipeHintDistance, y: 0)
}) { (success) in
UIView.animate(withDuration: 0.2, delay: 0, options: [.curveLinear], animations: {
self.cellBackgroundView.transform = .identity
})
}
}
Step 3 - Trigger the Animation
In the viewDidLoad of the view controller that has the table view, I have this code:
if self.tableView.visibleCells.count > 0 {
let cell = self.tableView.visibleCells[0] as! TableViewCell
cell.animateSwipeHint()
}
Example:
Video Solution
I created a video if you'd like a more in-depth walkthrough of this solution:
https://youtu.be/oAGoFd_GrxE
I have a piece of code that I saw long time ago to animate a view. Since our UITableViewCell is also a view, we can use it :) You just need to get your visible cell to animate, like so:
if let visibleCell = self.tableView.cellForRow(at: IndexPath(row: 0, section: 0)) as? CustomCell {
print("Started animation...")
let animation = CAKeyframeAnimation(keyPath: "transform.translation.x")
animation.timingFunction = CAMediaTimingFunction(name: kCAMediaTimingFunctionLinear)
animation.duration = 0.6
animation.values = [-20.0, 20.0, -20.0, 20.0, -10.0, 10.0, -5.0, 5.0, 0.0 ]
visibleCell.layer.add(animation, forKey: "shake")
}
Let me know if this helps. Tested it.
EDIT:
Animating your UITableView to let the user see that they can swipe on a cell is pretty easy, try it like so:
DispatchQueue.main.asyncAfter(deadline: .now() + .seconds(1)) {
self.tableView.setEditing(true, animated: true)
DispatchQueue.main.asyncAfter(deadline: .now() + .seconds(1)) {
self.tableView.setEditing(false, animated: true)
}
}
HOWEVER, if you want to swipe programmatically your cell to show your custom row actions, (I've been researching this for an hour), you can only achieve this, as far as I know, by using method swizzling. See this SO answer: http://codejaxy.com/q/186524/ios-swift-uitableview-how-to-present-uitableviewrowactions-from-pressing-a-button

UIView animation with autolayout and child views

I have a weird problem that seems to be fairly easy to solve. I think I could use some workaround to be able to have the behavior that I want but I want to know if there is a better way to do it.
I have a view called contentView (blue in the image) that it will expand its height using a UIView.animation, this is no problem at all and works as expected.
The problem here is that this view has a child component (a button) that has an autolayout constraint to its bottom equal to 22 like this:
This is the autolayout constraint:
If I do the height resize without the animation it works fine, the view height change and the button are always 22 points of the bottom of the contentView. But when I use an animation to make this change more smoothy and user-friendly the button moves to the end position before the animation even start.
I want to know how I could achieve a smooth animation here but with the button moving along its parent view
The part of the code that handles the animation is pretty straightforward but I'll post it in here:
#IBAction func openDetail(_ sender: ExpandCourseDetail) {
let rotation = sender.getOpen() ? CGAffineTransform.identity : CGAffineTransform(rotationAngle: CGFloat.pi)
UIView.animate(withDuration: 0.5, delay: 0.1, options: [.curveEaseInOut], animations: {
sender.transform = rotation
}, completion: {
success in
sender.setOpen(!sender.getOpen())
})
UIView.animate(withDuration: 1.0, delay: 0.5, options: [.curveEaseInOut], animations: {
self.contentView.frame.size.height = sender.getOpen() ? self.contentView.frame.height - 300 : self.contentView.frame.height + 300
}, completion: nil)
}
As a side note, the button itself has an animation that rotates the button 180 degrees to show the user that the view is expanding.
Thank you so much for your help.
It's super easy with constraints, just create a superView height constraint IBOutlet and change its constant value.
#IBAction func btnPressed(_ sender: UIButton) {
self.toggleButton.isSelected = !sender.isSelected
//Animation starts here
self.view.layoutIfNeeded()
UIView.animate(withDuration: 0.7) {
if self.toggleButton.isSelected {
//transform button
self.toggleButton.transform = CGAffineTransform(rotationAngle: CGFloat(Double.pi))
//change your ParentView height to desired one
self.constContentViewHeight.constant = self.view.frame.size.height - 220
self.view.layoutIfNeeded()
} else {
self.toggleButton.transform = CGAffineTransform(rotationAngle: CGFloat(Double.pi*2))
// Set height constraint to original value
self.constContentViewHeight.constant = 250
self.view.layoutIfNeeded()
}
}
}
I have created a demo, check it out.
The issue you are facing is due to two animation blocks. So I have changed some lines and put both button transformation and height animation into one animation block.
func openDetail(_ sender: ExpandCourseDetail) {
let isOpen = sender.getOpen() ? CGAffineTransform.identity : CGAffineTransform(rotationAngle: CGFloat.pi)
UIView.animate(withDuration: 1.0, delay: 0.5, options: [.curveEaseInOut], animations: {
sender.transform = rotation
self.contentView.frame.size.height = self.contentView.frame.height + (isOpen ? 300 : -300)
}, completion: { (success) in
sender.setOpen(!isOpen)
})
}

Perfect Swift3 Boing

To animate a bar opening...
#IBOutlet var barHeight: NSLayoutConstraint!
barHeight.constant = barShut?30:100
self.view.layoutIfNeeded()
t = !barShut?30:100
UIView.animate(withDuration: 0.15,
delay: 0,
options: UIViewAnimationOptions.curveEaseOut,
animations: { () -> Void in
self.barHeight.constant = t
self.view.layoutIfNeeded()
},
completion: {_ in
Screen.barShut = !Screen.barShut
}
)
That's great ...
But how would you make it boing like this?
(The only way I'd know to do this is, use CADisplayLink, with a few lines of code for a spring decaying.) Is this available in UIKit?
You can use the spring animation method that is built in to UIView:
func toggleBar() -> Void {
self.view.layoutIfNeeded()
let newHeight:CGFloat = !barShut ? 30:100
barShut = !barShut
barHeightConstraint.constant = newHeight
UIView.animate(withDuration: 1.5, delay: 0, usingSpringWithDamping: 0.2, initialSpringVelocity: 3, options: [], animations: {
self.view.layoutIfNeeded()
}, completion: nil)
}
You will want a longer animation duration than 0.15 of a second in order for the bounce to seem realistic; I think the values I have look pretty good, but you can play with them to get the exact effect you are after.
Since the animation duration is longer, I found that I could tap the button the triggered the open/shut while the previous animation was still running. Setting barShut in the completion block meant that the bar didn't react to all taps. I moved the toggle outside of the animation to address this.

Custom Segue Class UIView Animation Issue

I am having trouble creating a custom segue using swift 3 and iOS 8. I am trying to transition between view controllers by fading from one VC to a black screen and then fading from black to my second VC. I tried to implement the segue by creating a custom segue using the code below, but it is not working as I would like it to. My goal is to perform an animation when the black square goes from 0.5 alpha to 1.0 alpha, then present my second view controller, then set the black square from 1.0 alpha back to 0.5 alpha and delete it. Right now, it does the first part correctly but after the animation finishes you can see the first VC for a brief instant before the second VC pops up. How should I change my code to make the transition smoother and get the desired result?
override func perform() {
let sourceVC = self.source
let destinationVC = self.destination
let square = UIView(frame: CGRect(x: 0, y: 0, width: UIScreen.main.bounds.width, height: UIScreen.main.bounds.height))
square.alpha = 0.5
square.backgroundColor = UIColor.black
sourceVC.view.addSubview(square)
UIView.animate(withDuration: 0.2, animations: {
square.alpha = 1.0
})
UIView.animate(withDuration: 0.2, delay: 0.2, animations: {
square.alpha = 0.5
}) { (finished) in
sourceVC.present(destinationVC, animated: false, completion: nil)
}
}
Update your code like below and try:
UIView.animate(withDuration: 0.2, animations: {
square.alpha = 1.0
UIView.animate(withDuration: 0.2, delay: 0.2, animations: {
square.alpha = 0.5
}) { (finished) in
DispatchQueue.main.async {
sourceVC.present(destinationVC, animated: false, completion: nil)
}
})
}

Take control of scrollView mid animation of contentOffset

When I tap my scrollView it activates a UITapGestureRecognizer that animates the contentOffset for about 2 seconds. How could I allow the user to interrupt the animation and take full control of the scrollView again when they drag? Right now the user has to wait until the end of the animation to start interacting with the scrollView again.
Note: self refers to the scrollView
Tap set up:
let singleTap = UITapGestureRecognizer(target: self, action: "subtleBounce:")
singleTap.cancelsTouchesInView = false
self.addGestureRecognizer(singleTap)
So when the user taps:
func subtleBounce(gesture : UITapGestureRecognizer) {
let originalFrame = self.frame
UIView.animateWithDuration(0.1, delay: 0.0, usingSpringWithDamping: 1.5, initialSpringVelocity: 1.5, options: UIViewAnimationOptions.CurveLinear, animations: {
self.contentOffset.y -= 10.0
}, completion: {
Void in
UIView.animateWithDuration(0.6, delay: 0.0, usingSpringWithDamping: 0.1, initialSpringVelocity: 3.0, options: UIViewAnimationOptions.CurveLinear, animations: {
self.contentOffset.y += 10.0 }, completion: { Void in
})
})
}
So the code above works as intended.
Here is what I've tried to stop the animation and give the user control of the scrollView again:
let drag = UISwipeGestureRecognizer(target: self, action: "stopScrollAnimation:")
drag.cancelsTouchesInView = false
self.addGestureRecognizer(drag)
and elsewhere:
func stopScrollAnimation(gesture : UISwipeGestureRecognizer) {
self.layer.removeAllAnimations()
self.setContentOffset(CGPoint(x: 0.0, y: 0.0), animated: false)
}
However this DOES NOT work as intended. The animation still controls the scrollView and the user cannot interact with it.
If you want an example what I mean, look at the iOS7/8 lockscreen. After tapping the screen it also starts an animation. The user can take control of the scrollView mid animation however.
edit: accepting answers in swift or obj-c.
Add AllowUserInteraction to your animation options.

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