How to show activity indicator while tableView loads? - ios

Question

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?

Answer 1

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

Answer 2

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

Answer 3

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()
}
...
}

Answer 4

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()

Answer 5

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()

Answer 6

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

Answer 7

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)

Answer 8

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()
})
}

Answer 9

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
}

Answer 10

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()
}

Answer 11

#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)
}
}
}

Answer 12

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