I have created this custom code to create a loader in my project. The problem is that I have to copy and paste this function in all my classes. Is there any way I can declare this code in one global functions class and just use them wherever I want to use by calling.
import NVActivityIndicatorView
let activityIndicatorView = NVActivityIndicatorView(frame: CGRect(x: 80, y: 80, width: 60, height:60), type: .ballTrianglePath, color: .black)
let blurView = UIView()
func startLoader(){
DispatchQueue.main.async
{
self.blurView.isHidden = false
self.blurView.frame = self.view.frame
self.blurView.backgroundColor = UIColor.gray.withAlphaComponent(0.5)
self.view.addSubview(self.blurView)
self.activityIndicatorView.center = self.blurView.center
self.view.addSubview(self.activityIndicatorView)
self.activityIndicatorView.startAnimating()
}
}
func stopLoader(){
DispatchQueue.main.async {
self.activityIndicatorView.stopAnimating()
self.blurView.isHidden = true
}
}
First Create function to get activityIndicatorView and blurView. Because you don't need to repeat code in everywhere.And easily change entire loader views in one place
Class Helper {
static func getLoaderViews()->(UIView,NVActivityIndicatorView){
let activityIndicatorView = NVActivityIndicatorView(frame: CGRect(x: 80, y: 80, width: 60, height:60), type: .ballTrianglePath, color: .black)
let blurView = UIView()
// create your components,customise and return
return (blurView,activityIndicatorView)
}
}
now create a UIViewController Extension to start or stop loader
extension UIViewController {
func addLoaderToView(view:UIView,blurView:UIView ,activityIndicatorView:NVActivityIndicatorView) {
blurView.isHidden = false
blurView.frame = view.frame
blurView.backgroundColor = UIColor.gray.withAlphaComponent(0.5)
view.addSubview(blurView)
activityIndicatorView.center = blurView.center
view.addSubview(activityIndicatorView)
activityIndicatorView.startAnimating()
}
func removeLoader(activityIndicatorView:NVActivityIndicatorView,blurView:UIView) {
activityIndicatorView.stopAnimating()
blurView.isHidden = true
}
}
Now you can easily add or remove loader in any UIViewController
let (blurView,activityIndicatorView) = Helper.getLoaderViews() //In your class scope
//where you want to start
addLoaderToView(view:self.view,blurView:blurView ,activityIndicatorView:activityIndicatorView)
//where you want to stop
removeLoader(activityIndicatorView:activityIndicatorView,blurView:blurView)
You can create UIView extension
extension UIView {
func showActivity() {
let activityIndicatorView = NVActivityIndicatorView(frame: CGRect(x: 80, y: 80, width: 60, height:60), type: .ballTrianglePath, color: .black)
let blurView = UIView()
DispatchQueue.main.async {
self.blurView.isHidden = false
self.blurView.frame = self.frame
self.blurView.backgroundColor = UIColor.gray.withAlphaComponent(0.5)
self.addSubview(self.blurView)
self.activityIndicatorView.center = self.blurView.center
self.addSubview(self.activityIndicatorView)
self.activityIndicatorView.startAnimating()
}
}
}
I'm creating a wallpaper app for iOS. I've created a UIImageView, but am stuck on saving the image. I have solved the permissions but am unable to have the user save the image. I created the save button itself, but I don't know to make save any image from the image array in the user's image gallery.
Here is my code so far:
class ViewController: UIViewController {
#IBOutlet var imageview: [UIScrollView]!
#IBOutlet weak var saveButton: UIButton!
#IBAction func saveButtonPressed(_ sender: UIButton) {
// TODO: - How to save the image here
}
let scrollView: UIScrollView = {
let scroll = UIScrollView()
scroll.isPagingEnabled = true
scroll.showsVerticalScrollIndicator = false
scroll.showsHorizontalScrollIndicator = false
scroll.frame = CGRect(x: 0, y: 0, width: UIScreen.main.bounds.width, height: UIScreen.main.bounds.height)
return scroll
}()
var imageArray = [UIImage]()
func setupImages(_ images: [UIImage]){
for i in 0..<images.count {
let imageView = UIImageView()
imageView.image = images[i]
let xPosition = UIScreen.main.bounds.width * CGFloat(i)
imageView.frame = CGRect(x: xPosition, y: 0, width: scrollView.frame.width, height: scrollView.frame.height)
imageView.contentMode = .scaleAspectFit
scrollView.contentSize.width = scrollView.frame.width * CGFloat(i + 1)
scrollView.addSubview(imageView)
//scrollView.delegate = (self as! UIScrollViewDelegate)
}
}
override func viewDidLoad() {
super.viewDidLoad()
// Do any additional setup after loading the view.
view.addSubview(scrollView)
imageArray = [#imageLiteral(resourceName: "1"),#imageLiteral(resourceName: "10"),#imageLiteral(resourceName: "9"),#imageLiteral(resourceName: "8"),#imageLiteral(resourceName: "3")]
setupImages(imageArray)
}
}
You will need to add a saveImage function:
func saveImage(image: UIImage) -> Bool {
guard let data = UIImageJPEGRepresentation(image, 1) ?? UIImagePNGRepresentation(image) else {
return false
}
guard let directory = try? FileManager.default.url(for: .documentDirectory, in: .userDomainMask, appropriateFor: nil, create: false) as NSURL else {
return false
}
do {
try data.write(to: directory.appendingPathComponent("fileName.png")!)
return true
} catch {
print(error.localizedDescription)
return false
}
}
And then in saveButtonPressed:
let success = saveImage(image: imageArray[0])
print("Did \(success ? "" : "not ")store image successfully")
You'll need to add some logic to actually select the image.
how can i select a subview and interact with it using swift and n subview. For now i have only 3 subviews and select 3 image with for.
But for example how can I remove the subview with tag 2 after i create it?
func addSubView() {
for index in 1...3 {
let image: UIImage = UIImage(named: String(index))!
imageView = UIImageView(image: image)
imageView.tag = index
imageView.isUserInteractionEnabled = true
let tapGesture = UITapGestureRecognizer(target: self, action: #selector(ViewController.removeSubview))
imageView.addGestureRecognizer(tapGesture)
imageView.frame = CGRect(x: randomNumber(range: 60...300), y: randomNumber(range: 60...400), width: 50, height: 50)
print(imageView)
self.backgroundImageView.addSubview(imageView)
}
}
func removeSubview() {
}
You could write a function removeSubviewWithTag(_:) that would take a tag number as a parameter:
func removeSubviewWithTag(_ tag: Int) {
if let viewWithTag2 = backgroundImageView.viewWithTag(tag) {
viewWithTag2.removeFromSuperview()
}
}
And then call it as desired:
removeSubviewWithTag(2)
If you want to know if the function was able to find and remove a subview, you could make it return a discardable Bool result:
#discardableResult func removeSubviewWithTag(_ tag: Int) {
if let viewWithTag2 = backgroundImageView.viewWithTag(tag) {
viewWithTag2.removeFromSuperview()
return true
} else {
return false
}
}
And call it as follows:
if removeSubviewWithTag(2) {
print("Removed view")
} else {
print("unable to remove view")
}
Maybe add them to an array? Using tags is rarely the best solution.
var imageViews = [UIImageView]()
func addSubView() {
for index in 1...3 {
let image: UIImage = UIImage(named: String(index))!
imageView = UIImageView(image: image)
imageView.tag = index
imageView.isUserInteractionEnabled = true
let tapGesture = UITapGestureRecognizer(target: self, action: #selector(ViewController.removeSubview))
imageView.addGestureRecognizer(tapGesture)
imageView.frame = CGRect(x: randomNumber(range: 60...300), y: randomNumber(range: 60...400), width: 50, height: 50)
print(imageView)
self.backgroundImageView.addSubview(imageView)
imageViews.append(imageView)
}
}
func removeSubview(at index: Int) {
imageViews[index].removeFromSuperview()
}
On Swift 3.0 how can I apply some animation effect to this slideshow? Cannot find animation effects related to animationWithDuration method.
let image1 = UIImage(named: "image1")!
let image2 = UIImage(named: "image2")!
let image3 = UIImage(named: "image3")!
var imagesArray : [UIImage] = []
override func viewDidLoad() {
super.viewDidLoad()
imagesArray = [image1, image2, image3]
myView.clipsToBounds = true
myView.animationImages = imagesArray
myView.animationDuration = 10.0
myView.animationRepeatCount = 0
myView.startAnimating()
}
It looks like you are using the build in frame animation for UIImageView. This is designed to just cycle through the images, like an animated gif. It doesn't really have more sophisticated animation than that. What you can do if you want transition effects is alternate between two image views and use the UIView Animation methods to switch between them. This just does a crossfade by manipulating alpha:
var images = [UIImage]()
var currentImageindex = 0
func animateImageViews() {
swap(&firstImageView, &secondImageView)
secondImageView.image = images[currentImageindex]
currentImageindex = (currentImageindex + 1) % images.count
UIView.animate(withDuration: 1, animations: {
self.firstImageView.alpha = 0
self.secondImageView.alpha = 1
}, completion: { _ in
self.animateImageViews()
})
}
Here is playground that shows how it works. You need to drop 2 images into the resources folder named 1.png and 2.png for it to work. Note that setting the view frames like this is horrible programming practice i just did it here for brevity. use interface builder and autolayout in your actual code.
import PlaygroundSupport
import UIKit
class Demo: UIViewController {
let button = UIButton()
var firstImageView = UIImageView()
var secondImageView = UIImageView()
var images = [UIImage]()
var currentImageindex = 0
override func viewDidLoad() {
view.addSubview(firstImageView)
view.addSubview(secondImageView)
images.append(UIImage(named: "1.png")!)
images.append(UIImage(named: "2.png")!)
firstImageView.image = images[0]
secondImageView.image = images[1]
}
override func viewDidLayoutSubviews() {
super.viewDidLayoutSubviews()
firstImageView.frame = view.frame
secondImageView.frame = view.frame
}
override func viewDidAppear(_ animated: Bool) {
animateImageViews()
}
func animateImageViews() {
swap(&firstImageView, &secondImageView)
secondImageView.image = images[currentImageindex]
currentImageindex = (currentImageindex + 1) % images.count
UIView.animate(withDuration: 1, animations: {
self.firstImageView.alpha = 0
self.secondImageView.alpha = 1
}, completion: { _ in
self.animateImageViews()
})
}
}
let viewcontroller = Demo()
viewcontroller.view.frame = CGRect(x: 0, y: 0, width: 100, height: 100)
PlaygroundPage.current.liveView = viewcontroller.view
When I switch between my tabs it loads some seconds and I want to know that my data is loading. For that I decided to add an activity indicator.
I wrote a little function:
func showActivityIndicator() {
dispatch_async(dispatch_get_main_queue()) {
self.spinner = UIActivityIndicatorView(activityIndicatorStyle: .WhiteLarge)
self.spinner.frame = CGRect(x: 0.0, y: 0.0, width: 80.0, height: 80.0)
self.spinner.center = CGPoint(x:self.loadingView.bounds.size.width / 2, y:self.loadingView.bounds.size.height / 2)
self.loadingView.addSubview(self.spinner)
self.view.addSubview(self.loadingView)
self.spinner.startAnimating()
}
}
that will show my indicator. And try to use it when I tapped from my infoController to button:
#IBAction func goToMainFromInfo(sender: AnyObject) {
self.showActivityIndicator()
self.performSegueWithIdentifier("fromMainToInfoWActivity", sender: nil)
self.hideActivityIndicator()
}
}
I show it before segue perform and hide after. It doesn't help me. When I did try to use sync:
#IBAction func goToMainFromInfo(sender: AnyObject) {
dispatch_async(dispatch_get_main_queue()) {
self.showActivityIndicator()
self.performSegueWithIdentifier("fromMainToInfoWActivity", sender: nil)
self.hideActivityIndicator()
}
}
But it doesn't help too. When I press to tab it opacity becomes 0.5 and I wait while it loading. But I do not see my activity indicator.
What is the problem?
Just try this:
var indicator = UIActivityIndicatorView()
func activityIndicator() {
indicator = UIActivityIndicatorView(frame: CGRectMake(0, 0, 40, 40))
indicator.activityIndicatorViewStyle = UIActivityIndicatorViewStyle.Gray
indicator.center = self.view.center
self.view.addSubview(indicator)
}
And where you want to start animating
indicator.startAnimating()
indicator.backgroundColor = UIColor.whiteColor()
For stop:
indicator.stopAnimating()
indicator.hidesWhenStopped = true
Note: Avoid the calling of start and stop at the same time. Just give some conditions.
SWIFT : 4.2
Just try this:
var indicator = UIActivityIndicatorView()
func activityIndicator() {
indicator = UIActivityIndicatorView(frame: CGRect(x: 0, y: 0, width: 40, height: 40))
indicator.style = UIActivityIndicatorView.Style.gray
indicator.center = self.view.center
self.view.addSubview(indicator)
}
And where you want to start animating
activityIndicator()
indicator.startAnimating()
indicator.backgroundColor = .white
For stop:
indicator.stopAnimating()
indicator.hidesWhenStopped = true
Swift 3.0
// UIView Extension
fileprivate var ActivityIndicatorViewAssociativeKey = "ActivityIndicatorViewAssociativeKey"
public extension UIView {
var activityIndicatorView: UIActivityIndicatorView {
get {
if let activityIndicatorView = getAssociatedObject(&ActivityIndicatorViewAssociativeKey) as? UIActivityIndicatorView {
return activityIndicatorView
} else {
let activityIndicatorView = UIActivityIndicatorView(frame: CGRect(x: 0, y: 0, width: 40, height: 40))
activityIndicatorView.activityIndicatorViewStyle = .gray
activityIndicatorView.color = .gray
activityIndicatorView.center = center
activityIndicatorView.hidesWhenStopped = true
addSubview(activityIndicatorView)
setAssociatedObject(activityIndicatorView, associativeKey: &ActivityIndicatorViewAssociativeKey, policy: .OBJC_ASSOCIATION_RETAIN_NONATOMIC)
return activityIndicatorView
}
}
set {
addSubview(newValue)
setAssociatedObject(newValue, associativeKey:&ActivityIndicatorViewAssociativeKey, policy: .OBJC_ASSOCIATION_RETAIN_NONATOMIC)
}
}
}
// NSObject Extension
public extension NSObject {
func setAssociatedObject(_ value: AnyObject?, associativeKey: UnsafeRawPointer, policy: objc_AssociationPolicy) {
if let valueAsAnyObject = value {
objc_setAssociatedObject(self, associativeKey, valueAsAnyObject, policy)
}
}
func getAssociatedObject(_ associativeKey: UnsafeRawPointer) -> Any? {
guard let valueAsType = objc_getAssociatedObject(self, associativeKey) else {
return nil
}
return valueAsType
}
}
start animation
tableView.activityIndicatorView.startAnimating()
stop animation
tableView.activityIndicatorView.stopAnimating()
You can find more code in Magic
Swift 2+
class ViewController: UITableViewController {
weak var activityIndicatorView: UIActivityIndicatorView!
override func viewDidLoad() {
super.viewDidLoad()
let activityIndicatorView = UIActivityIndicatorView(activityIndicatorStyle: UIActivityIndicatorViewStyle.Gray)
tableView.backgroundView = activityIndicatorView
self.activityIndicatorView = activityIndicatorView
activityIndicatorView.startAnimating()
}
...
}
I use two extension methods to add an UIActivityIndicatorView as the backgroundView of the tableview.
extension UITableView {
func showActivityIndicator() {
DispatchQueue.main.async {
let activityView = UIActivityIndicatorView(style: .medium)
self.backgroundView = activityView
activityView.startAnimating()
}
}
func hideActivityIndicator() {
DispatchQueue.main.async {
self.backgroundView = nil
}
}
}
You can show/hide it like this.
tableView.showActivityIndicator()
tableView.hideActivityIndicator()
This code can help you :)
let indicator:UIActivityIndicatorView = UIActivityIndicatorView (activityIndicatorStyle: UIActivityIndicatorViewStyle.Gray)
indicator.color = UIColor .magentaColor()
indicator.frame = CGRectMake(0.0, 0.0, 10.0, 10.0)
indicator.center = self.view.center
self.view.addSubview(indicator)
indicator.bringSubviewToFront(self.view)
indicator.startAnimating()
SWIFT
Place this below your class:
let indicator:UIActivityIndicatorView = UIActivityIndicatorView (activityIndicatorStyle: UIActivityIndicatorViewStyle.Gray)
Place this in your loadView():
indicator.color = UIColor .magentaColor()
indicator.frame = CGRectMake(0.0, 0.0, 10.0, 10.0)
indicator.center = self.view.center
self.view.addSubview(indicator)
indicator.bringSubviewToFront(self.view)
indicator.startAnimating()
In my case, I am requesting json objects through a func request, so I placed this at the end of that function to remove the activity indicator once the data loads:
self.indicator.stopAnimating()
self.indicator.hidesWhenStopped = true
Another approach, In my code I added an extension for UITableView (Swift 2.3) :
extension UITableView {
func activityIndicator(center: CGPoint = CGPointZero, loadingInProgress: Bool) {
let tag = 12093
if loadingInProgress {
var indicator = UIActivityIndicatorView()
indicator = UIActivityIndicatorView(frame: CGRectMake(0, 0, 40, 40))
indicator.tag = tag
indicator.activityIndicatorViewStyle = UIActivityIndicatorViewStyle.WhiteLarge
indicator.color = //Your color here
indicator.center = center
indicator.startAnimating()
indicator.hidesWhenStopped = true
self.superview?.addSubview(indicator)
}else {
if let indicator = self.superview?.viewWithTag(tag) as? UIActivityIndicatorView { {
indicator.stopAnimating()
indicator.removeFromSuperview()
}
}
}
}
Note : My tableview is embedded in a UIView (superview)
Update Swift 4.2:
1.call the activityIndicator function on viewDidLoad
eg:
var indicator = UIActivityIndicatorView()
override func viewDidLoad() {
//Initializing the Activity Indicator
activityIndicator()
//Starting the Activity Indicator
indicator.startAnimating()
//Call Your WebService or API
callAPI()
}
Here is the Code For Adding ActivityIndicator as Subview
func activityIndicator() {
indicator = UIActivityIndicatorView(frame: CGRect(x: 0, y: 0, width: 40, height: 40))
indicator.style = UIActivityIndicatorView.Style.whiteLarge
indicator.color = .red
indicator.center = self.view.center
self.view.addSubview(indicator)
}
2. Do UI related Operations or API Call and stop activity indicator
func callAPI() {
YourModelClass.fetchResult(someParams,
completionHandler: { (response) in
//Do necessary UIUpdates
//And stop Activity Indicator
self.indicator.stopAnimating()
})
}
func setupSpinner(){
spinner = UIActivityIndicatorView(frame: CGRect(x: 0, y: 0, width: 40, height:40))
spinner.color = UIColor(Colors.Accent)
self.spinner.center = CGPoint(x:UIScreen.main.bounds.size.width / 2, y:UIScreen.main.bounds.size.height / 2)
self.view.addSubview(spinner)
spinner.hidesWhenStopped = true
}
Using "lazy var". It's better than function
fileprivate lazy var activityIndicatorView: UIActivityIndicatorView = {
let activityIndicatorView = UIActivityIndicatorView(activityIndicatorStyle: .gray)
activityIndicatorView.hidesWhenStopped = true
// Set Center
var center = self.view.center
if let navigationBarFrame = self.navigationController?.navigationBar.frame {
center.y -= (navigationBarFrame.origin.y + navigationBarFrame.size.height)
}
activityIndicatorView.center = center
self.view.addSubview(activityIndicatorView)
return activityIndicatorView
}()
Just start the spinner anywhere
like this
func requestData() {
// Request something
activityIndicatorView.startAnimating()
}
#brocolli's answer for swift 4.0. You have to use objc_ before getting or setting associated objects. According to the documentation, The APIs of getting and setting the associated object in Swift are:
func objc_getAssociatedObject(object: AnyObject!,
key: UnsafePointer<Void>
) -> AnyObject!
func objc_setAssociatedObject(object: AnyObject!,
key: UnsafePointer<Void>,
value: AnyObject!,
policy: objc_AssociationPolicy)
Implementation:
import UIKit
fileprivate var ActivityIndicatorViewAssociativeKey = "ActivityIndicatorViewAssociativeKey"
extension UIView {
var activityIndicatorView: UIActivityIndicatorView {
get {
if let activityIndicatorView = objc_getAssociatedObject(self, &ActivityIndicatorViewAssociativeKey) as? UIActivityIndicatorView {
return activityIndicatorView
} else {
let activityIndicatorView = UIActivityIndicatorView(frame: CGRect(x: 0, y: 0, width: 40, height: 40))
activityIndicatorView.activityIndicatorViewStyle = .gray
activityIndicatorView.color = .gray
activityIndicatorView.center = center
activityIndicatorView.hidesWhenStopped = true
addSubview(activityIndicatorView)
objc_setAssociatedObject(self, &ActivityIndicatorViewAssociativeKey, activityIndicatorView, .OBJC_ASSOCIATION_RETAIN_NONATOMIC)
return activityIndicatorView
}
}
set {
addSubview(newValue)
objc_setAssociatedObject(self, &ActivityIndicatorViewAssociativeKey, newValue, .OBJC_ASSOCIATION_RETAIN_NONATOMIC)
}
}
}
In order to place the UIActivityIndicator in foreground, even over the eventual UITableViewController separators, I have adopted this solution.
I have add the UIActivityIndicator programmatically, and add it as a subview of my UINavigationController
var activityIndicator: UIActivityIndicatorView!
override func viewDidLoad() {
super.viewDidLoad()
// Code
// .... omissis
// Set activity indicator
activityIndicator = UIActivityIndicatorView(style: .whiteLarge)
activityIndicator.color = UIColor.darkGray
activityIndicator.center = tableView.center
activityIndicator.hidesWhenStopped = true
activityIndicator.stopAnimating()
self.navigationController?.view.addSubview(activityIndicator)
}
I have just start & stop it when needed (in my case):
func animateActivityIndicator(_ sender: Any ) {
guard let vc = sender as? UIViewController else { return }
if let v = vc as? MyTableViewController {
if v.activityIndicator.isAnimating {
v.activityIndicator.stopAnimating()
} else {
v.activityIndicator.startAnimating()
}
}
// Others UIViewController or UITableViewController follows...
// all of them exhibits an activityIndicator variable
// implemented programmatically or with the storyboard
}
PS. My environment is Xcode 10.0, iOS 12.0