Here is my code. I am using KeyboardHelper library for managing keyboard states and getting keyboard height, and also SnapKit. I have a text field that triggers keyboard. When a keyboard is visible I want to raise blue box above keyboard bounds, so it's visible. So far I failed to do so. Can you please help me with my code?
private var keyboardHelper : KeyboardHelper?
let box = UIView()
override func viewDidLoad() {
super.viewDidLoad()
keyboardHelper = KeyboardHelper(delegate: self)
guard let superview = self.view else {
return
}
box.backgroundColor = UIColor.blue
superview.addSubview(box)
box.snp.makeConstraints { make in
make.bottom.equalTo(superview.snp.bottom).offset(-16)
make.width.equalTo(200)
make.centerX.equalTo(superview)
make.height.equalTo(100)
}
}
func keyboardWillAppear(_ info: KeyboardAppearanceInfo) {
UIView.animate(withDuration: TimeInterval(info.animationDuration), delay: 0, options: info.animationOptions, animations: {
self.box.snp.updateConstraints({ make in
make.bottom.equalTo(info.endFrame.size.height).offset(10)
})
self.box.layoutIfNeeded()
}, completion: nil)
}
According to SnapKit docs:
if you are only updating the constant value of the constraint you can use the method snp.updateConstraints
You need to use snp.remakeConstraints in your case. Furthermore, you should probably call layoutIfNeeded on superview.
Optionally you could get rid of changing constraints and just animate proper transforms on show:
box.transform = CGAffineTransform(translationX: 0.0, y: neededTranslation)
on hide:
box.transform = .identity
Related
FirebaseUI has a nice pre-buit UI for Swift. I'm trying to position an image view above the login buttons on the bottom. In the example below, the imageView is the "Hackathon" logo. Any logo should be able to show in this, if it's called "logo", since this shows the image as aspectFit.
According to the Firebase docs page:
https://firebase.google.com/docs/auth/ios/firebaseui
You can customize the signin screen with this function:
func authPickerViewController(forAuthUI authUI: FUIAuth) -> FUIAuthPickerViewController {
return FUICustomAuthPickerViewController(nibName: "FUICustomAuthPickerViewController",
bundle: Bundle.main,
authUI: authUI)
}
Using this code & poking around with subviews in the debuggers, I've been able to identify and color code views in the image below. Unfortunately, I don't think that the "true" size of these subview frames is set until the view controller presents, so trying to access the frame size inside these functions won't give me dimensions that I can use for creating a new imageView to hold a log. Plus accessing the views with hard-coded index values like I've done below, seems like a pretty bad idea, esp. given that Google has already changed the Pre-Built UI once, adding a scroll view & breaking the code of anyone who set the pre-built UI's background color.
func authPickerViewController(forAuthUI authUI: FUIAuth) -> FUIAuthPickerViewController {
// Create an instance of the FirebaseAuth login view controller
let loginViewController = FUIAuthPickerViewController(authUI: authUI)
// Set background color to white
loginViewController.view.backgroundColor = UIColor.white
loginViewController.view.subviews[0].backgroundColor = UIColor.blue
loginViewController.view.subviews[0].subviews[0].backgroundColor = UIColor.red
loginViewController.view.subviews[0].subviews[0].tag = 999
return loginViewController
}
I did get this to work by adding a tag (999), then in the completion handler when presenting the loginViewController I hunt down tag 999 and call a function to add an imageView with a logo:
present(loginViewController, animated: true) {
if let foundView = loginViewController.view.viewWithTag(999) {
let height = foundView.frame.height
print("FOUND HEIGHT: \(height)")
self.addLogo(loginViewController: loginViewController, height: height)
}
}
func addLogo(loginViewController: UINavigationController, height: CGFloat) {
let logoFrame = CGRect(x: 0 + logoInsets, y: self.view.safeAreaInsets.top + logoInsets, width: loginViewController.view.frame.width - (logoInsets * 2), height: self.view.frame.height - height - (logoInsets * 2))
// Create the UIImageView using the frame created above & add the "logo" image
let logoImageView = UIImageView(frame: logoFrame)
logoImageView.image = UIImage(named: "logo")
logoImageView.contentMode = .scaleAspectFit // Set imageView to Aspect Fit
// loginViewController.view.addSubview(logoImageView) // Add ImageView to the login controller's main view
loginViewController.view.addSubview(logoImageView)
}
But again, this doesn't seem safe. Is there a "safe" way to deconstruct this UI to identify the size of this button box at the bottom of the view controller (this size will vary if there are multiple login methods supported, such as Facebook, Apple, E-mail)? If I can do that in a way that avoids the hard-coding approach, above, then I think I can reliably use the dimensions of this button box to determine how much space is left in the rest of the view controller when adding an appropriately sized ImageView. Thanks!
John
This should address the issue - allowing a logo to be reliably placed above the prebuilt UI login buttons buttons + avoiding hard-coding the index values or subview locations. It should also allow for properly setting background color (also complicated when Firebase added the scroll view + login button subview).
To use: Create a subclass of FUIAuthDelegate to hold a custom view controller for the prebuilt Firebase UI.
The code will show the logo at full screen behind the buttons if there isn't a scroll view or if the class's private constant fullScreenLogo is set to false.
If both of these conditions aren't meant, the logo will show inset taking into account the class's private logoInsets constant and the safeAreaInsets. The scrollView views are set to clear so that a background image can be set, as well via the private let backgroundColor.
Call it in any signIn function you might have, after setting authUI.providers. Call would be something like this:
let loginViewController = CustomLoginScreen(authUI: authUI!)
let loginNavigationController = UINavigationController(rootViewController: loginViewController)
loginNavigationController.modalPresentationStyle = .fullScreen
present(loginNavigationController, animated: true, completion: nil)
And here's one version of the subclass:
class CustomLoginScreen: FUIAuthPickerViewController {
private var fullScreenLogo = false // false if you want logo just above login buttons
private var viewContainsButton = false
private var buttonViewHeight: CGFloat = 0.0
private let logoInsets: CGFloat = 16
private let backgroundColor = UIColor.white
private var scrollView: UIScrollView?
private var viewContainingButton: UIView?
override func viewWillAppear(_ animated: Bool) {
super.viewWillAppear(animated)
// set color of scrollView and Button view inside scrollView to clear in viewWillAppear to avoid a "color flash" when the pre-built login UI first appears
self.view.backgroundColor = UIColor.white
guard let foundScrollView = returnScrollView() else {
print("😡 Couldn't get a scrollView.")
return
}
scrollView = foundScrollView
scrollView!.backgroundColor = UIColor.clear
guard let foundViewContainingButton = returnButtonView() else {
print("😡 No views in the scrollView contain buttons.")
return
}
viewContainingButton = foundViewContainingButton
viewContainingButton!.backgroundColor = UIColor.clear
}
override func viewDidAppear(_ animated: Bool) {
super.viewDidAppear(animated)
// Create the UIImageView at full screen, considering logoInsets + safeAreaInsets
let x = logoInsets
let y = view.safeAreaInsets.top + logoInsets
let width = view.frame.width - (logoInsets * 2)
let height = view.frame.height - (view.safeAreaInsets.top + view.safeAreaInsets.bottom + (logoInsets * 2))
var frame = CGRect(x: x, y: y, width: width, height: height)
let logoImageView = UIImageView(frame: frame)
logoImageView.image = UIImage(named: "logo")
logoImageView.contentMode = .scaleAspectFit // Set imageView to Aspect Fit
logoImageView.alpha = 0.0
// Only proceed with customizing the pre-built UI if you found a scrollView or you don't want a full-screen logo.
guard scrollView != nil && !fullScreenLogo else {
print("No scrollView found.")
UIView.animate(withDuration: 0.25, animations: {logoImageView.alpha = 1.0})
self.view.addSubview(logoImageView)
self.view.sendSubviewToBack(logoImageView) // otherwise logo is on top of buttons
return
}
// update the logoImageView's frame height to subtract the height of the subview containing buttons. This way the buttons won't be on top of the logoImageView
frame = CGRect(x: x, y: y, width: width, height: height - (viewContainingButton?.frame.height ?? 0.0))
logoImageView.frame = frame
self.view.addSubview(logoImageView)
UIView.animate(withDuration: 0.25, animations: {logoImageView.alpha = 1.0})
}
private func returnScrollView() -> UIScrollView? {
var scrollViewToReturn: UIScrollView?
if self.view.subviews.count > 0 {
for subview in self.view.subviews {
if subview is UIScrollView {
scrollViewToReturn = subview as? UIScrollView
}
}
}
return scrollViewToReturn
}
private func returnButtonView() -> UIView? {
var viewContainingButton: UIView?
for view in scrollView!.subviews {
viewHasButton(view)
if viewContainsButton {
viewContainingButton = view
break
}
}
return viewContainingButton
}
private func viewHasButton(_ view: UIView) {
if view is UIButton {
viewContainsButton = true
} else if view.subviews.count > 0 {
view.subviews.forEach({viewHasButton($0)})
}
}
}
Hope this helps any who have been frustrated trying to configure the Firebase pre-built UI in Swift.
I have a custom presentation controller which shows a UIViewController as a "bottom sheet" above the current ViewController, and allows an interactive gesture to dismiss the presented modal. The modal's modalPresentationStyle is set to .current, and the transitioningDelegate is set to my custom class during init(). The current code works perfectly on iOS 11 and 12, but appears to "freeze" the device on iOS 9 and 10.
Here is where the animation takes place. I have confirmed the presentedFrame and dismissedFrame are correct.
extension BottomSheetPresentationManager: UIViewControllerAnimatedTransitioning {
func transitionDuration(
using transitionContext: UIViewControllerContextTransitioning?) -> TimeInterval {
return 0.25
}
func interactionControllerForPresentation(using animator: UIViewControllerAnimatedTransitioning) -> UIViewControllerInteractiveTransitioning? {
return self
}
func interactionControllerForDismissal(using animator: UIViewControllerAnimatedTransitioning) -> UIViewControllerInteractiveTransitioning? {
return self
}
func animateTransition(using transitionContext: UIViewControllerContextTransitioning) {
let key = presenting ? UITransitionContextViewControllerKey.to
: UITransitionContextViewControllerKey.from
let keyV = presenting ? UITransitionContextViewKey.to
: UITransitionContextViewKey.from
let controller = transitionContext.viewController(forKey: key)!
let view = transitionContext.view(forKey: keyV)!
if presenting {
transitionContext.containerView.addSubview(view)
}
let presentedFrame = transitionContext.finalFrame(for: controller)
var dismissedFrame = presentedFrame
switch direction {
case .left:
dismissedFrame.origin.x = -presentedFrame.width
case .right:
dismissedFrame.origin.x = transitionContext.containerView.frame.size.width
case .top:
dismissedFrame.origin.y = -presentedFrame.height
case .bottom:
dismissedFrame.origin.y = transitionContext.containerView.frame.size.height
}
let initialFrame = presenting ? dismissedFrame : presentedFrame
let finalFrame = presenting ? presentedFrame : dismissedFrame
// Runs when the animation finishes
let completionBlock: (Bool) -> Void = { (finished) in
// tell our transitionContext object that we've finished animating
if transitionContext.transitionWasCancelled {
if self.interactive {
transitionContext.cancelInteractiveTransition()
}
transitionContext.completeTransition(false)
} else {
if self.interactive {
finished ? transitionContext.finishInteractiveTransition() : transitionContext.cancelInteractiveTransition()
}
transitionContext.completeTransition(finished)
}
}
// Put what you want to animate here.
let animationBlock: () -> Void = {
view.frame = finalFrame
}
// Set up for the animation
let animationDuration = transitionDuration(using: transitionContext)
view.frame = initialFrame
// Perform a different animation based on whether we're interactive (performing a gesture) or not
if interactive {
// Do a linear animation so we match our dragging with our transition
UIView.animate(withDuration: animationDuration,
delay: 0,
options: .curveLinear,
animations: animationBlock,
completion: completionBlock)
} else {
// Do a spring animation with easing
UIView.animate(withDuration: animationDuration,
delay: 0,
usingSpringWithDamping: 0.8,
initialSpringVelocity: 0.45,
options: [.curveEaseInOut],
animations: animationBlock,
completion: completionBlock)
}
}
}
After much testing, I have figured out that the completion block on the UIView.animate block never gets called (completionBlock in the code), and in the Capture View Hierarchy view, it actually shows my presented view on top, with what looks like a screenshot of the view (UIVisualEffectView) directly under the presented menu.
What you are seeing there is my bottom menu (the UITableView with cells that you see in front), with a UIVisualEffectView behind it (appears to be a screenshot of the UICollection view behind that), and a UICollectionView that called the present() method for the menu.
What would cause the UIView.animate block not to complete? Is there any reason the behavior would differ between iOS 10 and 11? Any help would be greatly appreciated.
I want to create an animation like the iOS app facebook at tabswitch[1]. I have already tried to develop some kind of animation, the problem that occurs is that the old view controller becomes invisible directly on the switch, instead of fading out slowly while the new controller is sliding in fast.
I've found this SO question How to animate Tab bar tab switch with a CrossDissolve slide transition? but the as correct marked solution does not really work for me (it is not a slide it is a fade transition). What I'd also like to get is the function to make slide left or right to switch the tabs. Like it was on a older version of facebook.
What I've got so far is this:
extension TabBarController: UITabBarControllerDelegate {
func tabBarController(_ tabBarController: UITabBarController, shouldSelect viewController: UIViewController) -> Bool {
guard let fromView = selectedViewController?.view,
let toView = viewController.view else { return false }
if fromView != toView {
toView.transform = CGAffineTransform(translationX: -90, y: 0)
UIView.animate(withDuration: 0.25, delay: 0.0, options: .curveEaseInOut, animations: {
toView.transform = CGAffineTransform(translationX: 0, y: 0)
})
}; return true
}
}
class TabBarController: UITabBarController {
override func viewDidLoad() {
super.viewDidLoad()
delegate = self
}
}
How to fix this?
[1]
I would very much like to add a gif from the Facebook app. The problem is that I don't want to censor the video and just reveal too much of my data. (Even if fb already has them). Also on youtube I didn't find a suitable recording. Please try it yourself in the fb app in iOS.
You can use the following idea: https://samwize.com/2016/04/27/making-tab-bar-slide-when-selected/
Also, here's the code updated to Swift 4.1 and I also removed the force unwrappings:
import UIKit
class MyTabBarController: UITabBarController {
override func viewDidLoad() {
super.viewDidLoad()
delegate = self
}
}
extension MyTabBarController: UITabBarControllerDelegate {
func tabBarController(_ tabBarController: UITabBarController, shouldSelect viewController: UIViewController) -> Bool {
guard let tabViewControllers = tabBarController.viewControllers, let toIndex = tabViewControllers.index(of: viewController) else {
return false
}
animateToTab(toIndex: toIndex)
return true
}
func animateToTab(toIndex: Int) {
guard let tabViewControllers = viewControllers,
let selectedVC = selectedViewController else { return }
guard let fromView = selectedVC.view,
let toView = tabViewControllers[toIndex].view,
let fromIndex = tabViewControllers.index(of: selectedVC),
fromIndex != toIndex else { return }
// Add the toView to the tab bar view
fromView.superview?.addSubview(toView)
// Position toView off screen (to the left/right of fromView)
let screenWidth = UIScreen.main.bounds.size.width
let scrollRight = toIndex > fromIndex
let offset = (scrollRight ? screenWidth : -screenWidth)
toView.center = CGPoint(x: fromView.center.x + offset, y: toView.center.y)
// Disable interaction during animation
view.isUserInteractionEnabled = false
UIView.animate(withDuration: 0.3,
delay: 0.0,
usingSpringWithDamping: 1,
initialSpringVelocity: 0,
options: .curveEaseOut,
animations: {
// Slide the views by -offset
fromView.center = CGPoint(x: fromView.center.x - offset, y: fromView.center.y)
toView.center = CGPoint(x: toView.center.x - offset, y: toView.center.y)
}, completion: { finished in
// Remove the old view from the tabbar view.
fromView.removeFromSuperview()
self.selectedIndex = toIndex
self.view.isUserInteractionEnabled = true
})
}
}
So, you need to subclass UITabBarController and you also have to write the animation part, you can tweak the animation options (delay, duration, etc).
I hope it helps, cheers!
I've never seen Facebook so I don't know what the animation is. But you can have any animation you like when a tab bar controller changes its tab (child view controller), coherently and without any hacks, using the built-in mechanism that Apple provides for adding custom animation to a transition between view controllers. It's called custom transition animation.
Apple first introduced this mechanism in 2013. Here's a link to their video about it: https://developer.apple.com/videos/play/wwdc2013/218/
I immediately adopted this in my apps, and I think it makes them look a lot spiffier. Here's a demo of a tab bar controller custom transition that I like:
The really cool thing is that once you've decided what animation you want, making the transition interactive (i.e. drive it with a gesture instead of a button click) is easy:
Now, you might be saying: Okay, but that's not quite the animation I had in mind. No problem! Once you've got the hang of the custom transition architecture, changing the animation to anything you like is easy. In this variant, I just commented out one line so that the "old" view controller doesn't slide away:
So let your imagination run wild! Adopt custom transition animations, the way that iOS intends.
If you want something for pushViewController navigation, you can try this.
However, when switching between tabs on a TabBarController, this will not work. For that, I'd go with #mihai-erős 's solution
Change the Animation duration as per your liking, and assign this class to your navigation segues, for a Slide Animation.
class CustomPushSegue: UIStoryboardSegue {
override func perform() {
// first get the source and destination view controllers as UIviews so that they can placed in navigation stack
let sourceVCView = self.source.view as UIView!
let destinationVCView = self.destination.view as UIView!
let screenWidth = UIScreen.main.bounds.size.width
//create the destination view's rectangular frame i.e starting at 0,0 and equal to screenwidth by screenheight
destinationVCView?.transform = CGAffineTransform(translationX: screenWidth, y: 0)
//the destinationview needs to be placed on top(aboveSubView) of source view in the app window stack before being accessed by nav stack
// get the window and insert destination View
let window = UIApplication.shared.keyWindow
window?.insertSubview(destinationVCView!, aboveSubview: sourceVCView!)
// the animation: first remove the source out of screen by moving it at the left side of it and at the same time place the destination to source's position
// Animate the transition.
UIView.animate(withDuration: 0.3, animations: { () -> Void in
sourceVCView?.transform = CGAffineTransform(translationX: -screenWidth,y: 0)
destinationVCView?.transform = CGAffineTransform.identity
}, completion: { (Finished) -> Void in
self.source.present(self.destination, animated: false, completion: nil)
})
}
}
Im trying to implement a String list of messages to display on the screen for my login page. I need these messages to be able to scrolled through if the user decides to. I am using a label for my text. If the user does not scroll, then the messages will automatically scroll through. I tried using iCarousel but it does not achieve the effect I want.
You can use Libray https://github.com/cbpowell/MarqueeLabel
or easily you can also make auto scrollable label your own self like
func startAnimation()
{
//Animating the label automatically change as per your requirement
DispatchQueue.main.async(execute: {
UIView.animate(withDuration: 10.0, delay: 1, options: ([.curveLinear, .repeat]), animations: {
() -> Void in
self.demoLabel.center = CGPoint(x: 0 - self.demoLabel.bounds.size.width / 2, y: self.demoLabel.center.y)
}, completion: nil)
})
}
Usage
class ViewController: UIViewController {
let demoLabel: UILabel = {
let label = UILabel()
label.translatesAutoresizingMaskIntoConstraints = false
label.font = .systemFont(ofSize: 14)
label.textColor = .green
label.text = "This is the demo label for testing automatically scrolling of uilabel when user not clicked on label if user click on label the scrolling is stoped."
return label
}()
override func viewDidLoad() {
super.viewDidLoad()
view.addSubview(demoLabel)
startAnimation()
}
I have a UIView which contains subviews. The subviews are animated with constraints changes and layoutIfNeeded() function :
for i in 1...cardViews.count - 1 {
let currentCard = cardViews[i]
let previousCard = cardViews[i-1]
// Set new offset
currentCard.topConstraint?.constant = previousCard.contentView.frame.height + configuration.expandedOffset
}
// To animate constraints's changes
UIView.animate(withDuration: TimeInterval(duration), delay: 0, options: [.curveEaseOut], animations: {
self.layoutIfNeeded()
}, completion: nil)
But when I do this, it also animate the contraints changes of the parent. Something like this :
self.Height == containerView.Height
How can I call layoutIfNeeded() to animate my subviews but not the parent ?
EDIT : The side effect :
http://gph.is/2noI3w9
You can call this inside of your UIView.animate
for i in 1...cardViews.count - 1 {
let currentCard = cardViews[i]
currentCard.layoutIfNeeded()
}
Instead of
self.layoutIfNeeded()