Want to create an animation were user can slide the view from bottom similar to Apple Maps application in iOS. But having issues while handling gesture.
The code in my mainVC in which panVC is added as subview from bottom which works fine.(The panVC correctly comes at bottom)
func displayFromBottom {
let storyboard = UIStoryboard(name: "Main", bundle: nil)
listVC = storyboard.instantiateViewController(withIdentifier: “PanViewContr") as! PanViewContr
var startingFrame = self.view.bounds;
startingFrame.origin.y = startingFrame.size.height; //Starts from the bottom of the parent.
startingFrame.size.height = 100; //Has a height of 100.
var finalFrame = self.view.bounds;
finalFrame.origin.y = finalFrame.size.height - 100; //100 from the bottom of the parent.
listVC.view.frame = startingFrame
listVC.willMove(toParentViewController: self)
self.addChildViewController(listVC)
self.view.addSubview(listVC.view)
listVC.didMove(toParentViewController: self)
UIView.animate(withDuration: 0.5, animations: {
self.listVC.view.frame = finalFrame
}) { complete in
print("done”)
}
}
The code for PanVC were pan gesture is handled.
func slideViewVerticallyTo(_ y: CGFloat) {
self.view.frame.origin = CGPoint(x: 0, y: y)
}
#IBAction func panGesture(_ panGesture: UIPanGestureRecognizer) {
switch panGesture.state {
case .began, .changed:
// If pan started or is ongoing then
// slide the view to follow the finger
let translation = panGesture.translation(in: view)
let y = max(0, translation.y) //what should be value of y to make it dragable smoothly
self.slideViewVerticallyTo(y)
break
case .ended:
break
}
Any hint in right direction is highly appreciated.
I had created a movable extension that adds the ability to move UIView's around a screen the code for which you can see here: https://github.com/szweier/SZUtilities/blob/master/SZUtilities/Classes/UIView/Movable/UIView%2BMovable.swift you may be able to see something in this code that you are missing in your own. I'm sorry my answer isn't more specific but hopefully it gets you moving towards the correct answer.
I'm running into a weird situation where animating a UIImageView's alpha affects a UIButton which also exists on the same view.
My code:
func handleArrowAnimation(_ arrowImage: UIImageView, _ arrowImageXCenterConstraint: NSLayoutConstraint) {
arrowImageXCenterConstraint.constant = CGFloat(80)
UIView.animate(withDuration: 0.7, delay: 0, options: [.curveEaseInOut, .repeat, .autoreverse], animations: {
arrowImage.alpha = UIApplication.shared.userInterfaceLayoutDirection == .leftToRight ? 1 : 0.2
arrowImage.superview!.layoutIfNeeded()
}) { (completed) in
arrowImageXCenterConstraint.constant = CGFloat(0)
arrowImage.alpha = UIApplication.shared.userInterfaceLayoutDirection == .leftToRight ? 0.2 : 1
arrowImage.superview!.layoutIfNeeded()
}
}
The result:
I found that removing the call to layoutIfNeeded() prevents the UIButton alpha from changing, but of course it also prevents the arrow from moving - so it doesn't help me much.
The UIButton is not a subview of the arrowImage, and they don't share the same parent view (their parents share the same parent, though).
What am i missing here?
Thanks!
So apparently someone else had this issue and the answer is to make sure you start your animations after the view has loaded, for example in the viewDidAppear() method.
override func viewDidAppear(_ animated: Bool) {
super.viewDidAppear()
handleArrowAnimation()
}
Here is the link to previous question. There does not appear to be any explanation for the strange behaviour at this time.
I found this code online that implements the rubber band effect when panning a view:
#IBAction func viewDragged(sender: UIPanGestureRecognizer) {
let yTranslation = sender.translationInView(view).y
if (hasExceededVerticalLimit(topViewConstraint.constant)){
totalTranslation += yTranslation
topViewConstraint.constant = logConstraintValueForYPoisition(totalTranslation)
if(sender.state == UIGestureRecognizerState.Ended ){
animateViewBackToLimit()
}
} else {
topViewConstraint.constant += yTranslation
}
sender.setTranslation(CGPointZero, inView: view)
}
func logConstraintValueForYPoisition(yPosition : CGFloat) -> CGFloat {
return verticalLimit * (1 + log10(yPosition/verticalLimit))
}
The resulting effect is shown in the gif below:
However, I have trouble understanding how this code works, and reproducing this effect in my own projects. For instance, one of the things I do not understand is, when panning the green view upwards yTransition is going to be negative and negative numbers do not have logarithms (in the logConstraintValueForYPoisition(:) method). I would really appreciate it if someone could explain to me how this code works step by step.
The original post can be found here.
The log is not what you're thinking of. In fact, the snippet is incomplete. The repo can be found here.
The bouncing animation is here:
func animateViewBackToLimit() {
self.topViewConstraint.constant = self.verticalLimit
UIView.animateWithDuration(0.5, delay: 0, usingSpringWithDamping: 0.3, initialSpringVelocity: 10, options: UIViewAnimationOptions.AllowUserInteraction, animations: { () -> Void in
self.view.layoutIfNeeded()
self.totalTranslation = -200
}, completion: nil)
}
The log portion is for moving the green rectangle up. Once you reach an upward threshold (hasExceededVerticalLimit(topViewConstraint.constant)) you want the rectangle to stop moving as quick as you don't want it to keep up with your finger, you do this by calling logConstraintValueForYPoisition.
Note that if you have a positive value x, log(x) < x.
Note: I’ve already checked the following stack overflow issues:
27907570, 32229252, 26118141, 31604300
All I am trying to do is fade animate in a view (by alpha) when called by an IBAction attached to a button. Then reverse when a button on the view is hit.
My wrinkle may be that I'm using a secondary view that is on the ViewDock in the storyboard View. The view is added to the subview at the time of viewDidLoad where the frame/bounds are set to the same as the superview (for a full layover)
The reason this is done as an overlay view since it is a tutorial indicator.
The result (like many others who've listed this problem) is that the view (and contained controls) simply appears instantly and disappears as instantly. No fade.
I have tried animationWithDuration with delay, with and without completion, with transition, and even started with the old UIView.beginAnimations.
Nothing is working. Suggestions warmly welcomed.
The code is about as straight forward as I can make it:
Edit: Expanded the code to everything relevant
Edit2: TL;DR Everything works with the exception of UIViewAnimateWithDuration which seems to ignore the block and duration and just run the code inline as an immediate UI change. Solving this gets the bounty
#IBOutlet var infoDetailView: UIView! // Connected to the view in the SceneDock
override func viewDidLoad() {
super.viewDidLoad()
// Cut other vDL code that isn't relevant
setupInfoView()
}
func setupInfoView() {
infoDetailView.alpha = 0.0
view.addSubview(infoDetailView)
updateInfoViewRect(infoDetailView.superview!.bounds.size)
}
func updateInfoViewRect(size:CGSize) {
let viewRect = CGRect(origin: CGPointZero, size: size)
infoDetailView.frame = viewRect
infoDetailView.bounds = viewRect
infoDetailView.layoutIfNeeded()
infoDetailView.setNeedsDisplay()
}
override func viewWillTransitionToSize(size: CGSize, withTransitionCoordinator coordinator: UIViewControllerTransitionCoordinator) {
super.viewWillTransitionToSize(size, withTransitionCoordinator: coordinator)
updateInfoViewRect(size)
}
func hideInfoView() {
AFLog.enter(thisClass)
UIView.animateWithDuration(
2.0,
animations:
{
self.infoDetailView.alpha = 0.0
},
completion:
{ (finished) in
return true
}
)
AFLog.exit(thisClass)
}
func showInfoView() {
AFLog.enter(thisClass)
UIView.animateWithDuration(
2.0,
animations:
{
self.infoDetailView.alpha = 0.75
},
completion:
{ (finished) in
return true
}
)
AFLog.exit(thisClass)
}
// MARK: - IBActions
#IBAction func openInfoView(sender: UIButton) {
showInfoView()
}
#IBAction func closeInfoView(sender: UIButton) {
hideInfoView()
}
Please note, I started with the following:
func showInfoView() {
UIView.animateWithDuration(2.0, animations: { () -> Void in
self.infoDetailView.alpha = 0.75
})
}
func hideInfoView() {
UIView.animateWithDuration(2.0, animations: { () -> Void in
self.infoDetailView.alpha = 0.00
})
}
If you infoDetailView is under auto layout constraints you need to call layoutIfNeeded on the parent view inside animateWithDuration:
func showInfoView() {
self.view.layoutIfNeeded() // call it also here to finish pending layout operations
UIView.animate(withDuration: 2.0, animations: {
self.infoDetailView.alpha = 0.75
self.view.layoutIfNeeded()
})
}
Theoretically this should not be needed if you just change the .alpha value, but maybe this could be the problem in this case.
There are several strange things I can see,
first, remove:
infoDetailView.layoutIfNeeded()
infoDetailView.setNeedsDisplay()
Usually you don't need to call those methods manually unless you know exactly what you are doing.
Also, when you are changing the size:
infoDetailView.frame = viewRect
infoDetailView.bounds = viewRect
You never need to set both bounds and frame. Just set frame.
Also, you should probably make sure that the view actually doesn't ignore the frame by setting:
infoDetailView.translatesAutoresizingMaskIntoConstraints = true
Instead of resetting the frame, just set autoresize mask:
infoDetailView.autoresizingMask = [.FlexibleWidth, .FlexibleHeight]
Resulting in:
override func viewDidLoad() {
super.viewDidLoad()
// Cut other vDL code that isn't relevant
setupInfoView()
}
func setupInfoView() {
infoDetailView.alpha = 0.0
infoDetailView.translatesAutoresizingMaskIntoConstraints = true
infoDetailView.autoresizingMask = [.FlexibleWidth, .FlexibleHeight]
infoDetailView.frame = view.bounds
view.addSubview(infoDetailView)
}
func hideInfoView() {
...
}
I think this should actually help because immediate animations are often connected to size problems.
If the problem persists, you should check whether the infoDetailView in your animation is the same object as the infoDetailView you are adding to the controller.
For others looking to start an animation immediately when a view loads...
The animation won't work if you call UIView.animate(...) inside viewDidLoad. Instead it must be called from the viewDidAppear function.
override func viewDidAppear(_ animated: Bool) {
UIView.animate(withDuration: 3) {
self.otherView.frame.origin.x += 500
}
}
If the animation does not seem to execute then consider examining the state of each of your views, before you enter the animation block. For example, if the alpha is already set to 0.4 then the animation that adjusts your view alpha, will complete almost instantly, with no apparent effect.
Consider using a keyframe animation instead. This is what a shake animation in objective c looks like.
+(CAKeyframeAnimation*)shakeAnimation {
CAKeyframeAnimation *animation = [CAKeyframeAnimation animationWithKeyPath:#"transform"];
animation.values = #[[NSValue valueWithCATransform3D:CATransform3DMakeTranslation(-10.0, 0.0, 0.0)],
[NSValue valueWithCATransform3D:CATransform3DMakeTranslation(10.0, 0.0, 0.0)]];
animation.autoreverses = YES;
animation.repeatCount = 2;
animation.duration = 0.07;
return animation;
}
Here is a post that shows you how to adjust alpha with keyframes https://stackoverflow.com/a/18658081/1951992
Make sure infoDetailView's opaque is false.
https://developer.apple.com/library/ios/documentation/UIKit/Reference/UIView_Class/#//apple_ref/occ/instp/UIView/opaque
This property provides a hint to the drawing system as to how it should treat the view. If set to true, the drawing system treats the view as fully opaque, which allows the drawing system to optimize some drawing operations and improve performance. If set to false, the drawing system composites the view normally with other content. The default value of this property is true.
Try Below code. Just play with alpha and duration time to perfect it.
Hide func
func hideInfoView() {
AFLog.enter(thisClass)
UIView.animateWithDuration(
2.0,
animations:
{
self.infoDetailView.alpha = 0.8
},
completion:
{ (finished) in
UIView.animateWithDuration(
2.0,
animations:
{
self.infoDetailView.alpha = 0.4
},
completion:
{ (finished) in
self.infoDetailView.alpha = 0.0
}
)
}
)
AFLog.exit(thisClass)
}
Show func
func showInfoView() {
AFLog.enter(thisClass)
UIView.animateWithDuration(
2.0,
animations:
{
self.infoDetailView.alpha = 0.3
},
completion:
{ (finished) in
UIView.animateWithDuration(
2.0,
animations:
{
self.infoDetailView.alpha = 0.7
},
completion:
{ (finished) in
self.infoDetailView.alpha = 1.0
}
)
}
)
AFLog.exit(thisClass)
}
I've replicated your code and it work well, it's all ok.
Probably you must control constraints, IBOutlet and IBActions connections. Try to isolate this code into a new project if it's necessary.
Update: my code
and my storyboard and project folder photo:
Every object (view and buttons) are with default settings.
I've commented all AFLog lines (probably it's only any more "verbose mode" to help you) , the rest of your code is ok and it do what do you aspected from it, if you press open button the view fade in, and when you tap close button the view fade out.
PS Not relevant but i'm using xCode 7.3 , a new swift 2.2 project.
Use this code:
Swift 2
UIView.animateWithDuration(0.3, animations: { () -> Void in
self.infoDetailView.alpha = 0.0
})
Swift 3, 4, 5
UIView.animate(withDuration: 0.3, animations: { () -> Void in
self.infoDetailView.alpha = 0.0
})
Have you tried changing your showInfoView() to something more like toggleInfoView?
func toggleInfoView() {
let alpha = CGFloat(infoDetailView.alpha == 0 ? 1 : 0)
infoDetailView.alpha = alpha //this is where the toggle happens
}
It says that if your view's alpha is 0, then change it to 1. Else, make it 0.
If you need that to happen in an animation, try
#IBAction func openInfoView(sender: UIButton) {
UIView.animate(withDuration: 2.0, animations: {
self.toggleInfoView() //fade in/out infoDetailView when animating
})
}
You'll still want to keep that infoDetailView.alpha = 0.0 where you have it, coming from the viewDidLoad.
For UILabel component try to changes layer's background color instead.
Try this (Tested on Swift 4):
UIView.animate(withDuration: 0.2, animations: {
self.dateLabel.layer.backgroundColor = UIColor.red.cgColor;
})
Had a similar issue with animation not being performed.
Changed the function call use perform(aSelector: Selector, with: Any?, afterDelay: TimeInterval) in the form of perform(#selector(functionThatDoesAnimationOfAlphaValue), with: nil, afterDelay: 0) and it worked. Even with a TimeInterval set to 0.
In case someone else comes here wondering for a solution.
I want to rotate a UIImage, I have managed to do so with the code below, however when I press the rotate button again, the image does not rotate anymore, could someone please explain why?
#IBAction func rotate(sender: UIButton) {
UIView.animateWithDuration(0.2, animations: {
self.shape.transform = CGAffineTransformMakeRotation(CGFloat(M_PI_4) * 2)
})
}
You are changing your shape image view's transform to a new, fixed value. If you tap on it again, the transform already has that value. You set the transform to the same value again, which doesn't change anything.
You need to define an instance variable to keep track of the rotation.
var rotation: CGFloat = 0
#IBAction func rotate(sender: UIButton)
{
UIView.animateWithDuration(0.2, animations:
{
self.rotation += CGFloat(M_PI_4) * 2 //changed based on Daniel Storm's comment
self.shape.transform = CGAffineTransformMakeRotation(rotation)
})
}
That way, each time your tap the button you'll change the rotation variable from it's previous value to a new value and rotate to that new angle.