如何在iPhone屏幕中间显示活动指示灯？

Question

When we draw the image, we want to display the activity indicator. Can anyone help us?

Answer 1

UIActivityIndicatorView *activityView = [[UIActivityIndicatorView alloc]     
        initWithActivityIndicatorStyle:UIActivityIndicatorViewStyleWhiteLarge];

    activityView.center=self.view.center;
    [activityView startAnimating];
    [self.view addSubview:activityView];

Answer 2

If you are using Swift, this is how you do it

let activityView = UIActivityIndicatorView(activityIndicatorStyle: .whiteLarge)
activityView.center = self.view.center
activityView.startAnimating()

self.view.addSubview(activityView)

Answer 3

Code updated for Swift 3

Swift code

import UIKit
class ViewController: UIViewController {

    let activityIndicator = UIActivityIndicatorView(activityIndicatorStyle: UIActivityIndicatorViewStyle.whiteLarge)

    @IBOutlet weak var myBlueSubview: UIView!

    @IBAction func showButtonTapped(sender: UIButton) {
        activityIndicator.startAnimating()
    }

    @IBAction func hideButtonTapped(sender: UIButton) {
        activityIndicator.stopAnimating()
    }

    override func viewDidLoad() {
        super.viewDidLoad()

        // set up activity indicator
        activityIndicator.center = CGPoint(x: myBlueSubview.bounds.size.width/2, y: myBlueSubview.bounds.size.height/2)
        activityIndicator.color = UIColor.yellow
        myBlueSubview.addSubview(activityIndicator)
    }
}

Notes

• You can center the activity indicator in middle of the screen by adding it as a subview to the root view rather than myBlueSubview .

   activityIndicator.center = CGPoint(x: self.view.bounds.size.width/2, y: self.view.bounds.size.height/2) self.view.addSubview(activityIndicator) 

• You can also create the UIActivityIndicatorView in the Interface Builder. Just drag an Activity Indicator View onto the storyboard and set the properties. Be sure to check Hides When Stopped . Use an outlet to call startAnimating() and stopAnimating() . See this tutorial .

• Remember that the default color of the LargeWhite style is white. So if you have a white background you can't see it, just change the color to black or whatever other color you want.

   activityIndicator.color = UIColor.black 

• A common use case would be while a background task runs. Here is an example:

   // start animating before the background task starts activityIndicator.startAnimating() // background task DispatchQueue.global(qos: .userInitiated).async { doSomethingThatTakesALongTime() // return to the main thread DispatchQueue.main.async { // stop animating now that background task is finished self.activityIndicator.stopAnimating() } } 

Answer 4

This is the correct way:

UIActivityIndicatorView *activityIndicator = [[UIActivityIndicatorView alloc]initWithActivityIndicatorStyle:UIActivityIndicatorViewStyleGray];
activityIndicator.center = CGPointMake(self.view.frame.size.width / 2.0, self.view.frame.size.height / 2.0);
[self.view addSubview: activityIndicator];

[activityIndicator startAnimating];

[activityIndicator release];

Setup your autoresizing mask if you support rotation. Cheers!!!

Answer 5

如果您想添加文本以及活动指标，请查看http://nullpointr.wordpress.com/2012/02/27/ios-dev-custom-activityindicatorview/

Answer 6

Try this way

UIActivityIndicatorView *activityIndicator = [[UIActivityIndicatorView alloc]initWithActivityIndicatorStyle:UIActivityIndicatorViewStyleGray];
    activityIndicator.frame = CGRectMake(10.0, 0.0, 40.0, 40.0);
    activityIndicator.center = super_view.center;
    [super_view addSubview: activityIndicator];

[activityIndicator startAnimating];

Answer 7

If you want to center the spinner using AutoLayout, do:

UIActivityIndicatorView *activityView = [[UIActivityIndicatorView alloc] initWithActivityIndicatorStyle:UIActivityIndicatorViewStyleWhiteLarge];
[activityView startAnimating];
[self.view addSubview:activityView];
[self.view addConstraint:[NSLayoutConstraint constraintWithItem:activityView
                                                      attribute:NSLayoutAttributeCenterX
                                                      relatedBy:NSLayoutRelationEqual
                                                         toItem:self.view
                                                      attribute:NSLayoutAttributeCenterX
                                                     multiplier:1.0
                                                       constant:0.0]];
[self.view addConstraint:[NSLayoutConstraint constraintWithItem:activityView
                                                      attribute:NSLayoutAttributeCenterY
                                                      relatedBy:NSLayoutRelationEqual
                                                         toItem:self.view
                                                      attribute:NSLayoutAttributeCenterY
                                                     multiplier:1.0
                                                       constant:0.0]];

Answer 8

Swift 3, xcode 8.1

You can use small extension to place UIActivityIndicatorView in the centre of UIView and inherited UIView classes:

Code

extension UIActivityIndicatorView {

    convenience init(activityIndicatorStyle: UIActivityIndicatorViewStyle, color: UIColor, placeInTheCenterOf parentView: UIView) {
        self.init(activityIndicatorStyle: activityIndicatorStyle)
        center = parentView.center
        self.color = color
        parentView.addSubview(self)
    }
}

How to use

let activityIndicator = UIActivityIndicatorView(activityIndicatorStyle: .whiteLarge, color: .gray,  placeInTheCenterOf: view)
activityIndicator.startAnimating()

Full Example

In this example UIActivityIndicatorView placed in the centre of the ViewControllers view:

import UIKit

class ViewController: UIViewController {

    override func viewDidLoad() {
        super.viewDidLoad()
        // Do any additional setup after loading the view, typically from a nib.
        let activityIndicator = UIActivityIndicatorView(activityIndicatorStyle: .whiteLarge, color: .gray,  placeInTheCenterOf: view)
        activityIndicator.startAnimating()
    }
}

extension UIActivityIndicatorView {

    convenience init(activityIndicatorStyle: UIActivityIndicatorViewStyle, color: UIColor, placeInTheCenterOf parentView: UIView) {
        self.init(activityIndicatorStyle: activityIndicatorStyle)
        center = parentView.center
        self.color = color
        parentView.addSubview(self)
    }
}

Answer 9

You can set the position like this

        UIActivityIndicatorView *activityView = 
[[UIActivityIndicatorView alloc] initWithActivityIndicatorStyle:UIActivityIndicatorViewStyleWhite];
activityView.frame = CGRectMake(120, 230, 50, 50);
[self.view addSubview:activityView];

Accordingly change the frame size.....

Answer 10

For Swift 3 you can use the following:

 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 11

Swift 4, Autolayout version

func showActivityIndicator(on parentView: UIView) {
    let activityIndicator = UIActivityIndicatorView(activityIndicatorStyle: .gray)
    activityIndicator.startAnimating()
    activityIndicator.translatesAutoresizingMaskIntoConstraints = false

    parentView.addSubview(activityIndicator)

    NSLayoutConstraint.activate([
        activityIndicator.centerXAnchor.constraint(equalTo: parentView.centerXAnchor),
        activityIndicator.centerYAnchor.constraint(equalTo: parentView.centerYAnchor),
    ])
}

Answer 12

?If you want to try to do it by using interface, you can view my video for this . This way, you no need to write any code to show Activity Indicator in the middle of the iPhone screen.

Answer 13

import UIKit

class ViewController: UIViewController {

    @IBOutlet weak var textLbl: UILabel!

    var containerView = UIView()
    var loadingView = UIView()
    var activityIndicator = UIActivityIndicatorView()

    override func viewDidLoad() {
        super.viewDidLoad()

        let _  = Timer.scheduledTimer(withTimeInterval: 10, repeats: false) { (_) in
            self.textLbl.text = "Stop ActivitiIndicator"
            self.activityIndicator.stopAnimating()
            self.containerView.removeFromSuperview()
        }
    }

    override func didReceiveMemoryWarning() {
        super.didReceiveMemoryWarning()
    }

    @IBAction func palyClicked(sender: AnyObject){

        containerView.frame = self.view.frame
        containerView.backgroundColor = UIColor(red: 0/255, green: 0/255, blue: 0/255, alpha: 0.3)
        self.view.addSubview(containerView)

        loadingView.frame = CGRect(x: 0, y: 0, width: 80, height: 80)
        loadingView.center = self.view.center
        loadingView.backgroundColor = UIColor(red: 0/255, green: 0/255, blue: 0/255, alpha: 0.5)
        loadingView.clipsToBounds = true
        loadingView.layer.cornerRadius = 10
        containerView.addSubview(loadingView)

        activityIndicator.frame = CGRect(x: 0, y: 0, width: 40, height: 40)
        activityIndicator.activityIndicatorViewStyle = UIActivityIndicatorViewStyle.whiteLarge
        activityIndicator.center = CGPoint(x:loadingView.frame.size.width / 2, y:loadingView.frame.size.height / 2);
        activityIndicator.startAnimating()
        loadingView.addSubview(activityIndicator)

    }
}

Answer 14

轻松解决方案

UIApplication.sharedApplication.networkActivityIndicatorVisible = true/false

Answer 15

Hope this will work:

// create activity indicator 
UIActivityIndicatorView *activityIndicator = [[UIActivityIndicatorView alloc] 
    initWithFrame:CGRectMake(0.0f, 0.0f, 20.0f, 20.0f)];
[activityIndicator setActivityIndicatorViewStyle:UIActivityIndicatorViewStyleWhite];

...
 [self.view addSubview:activityIndicator];
// release it
[activityIndicator release];

Answer 16

I found a way to display activity Indicator with minimum code:

first of all import your UI Kit

import UIKit;

Then you have to initiate activity indicator

let activityIndicator:UIActivityIndicatorView = UIActivityIndicatorView();

Then just copy paste this functions below which are self explainatory and call them whereever you need them:

func startLoading(){
    activityIndicator.center = self.view.center;
    activityIndicator.hidesWhenStopped = true;
    activityIndicator.activityIndicatorViewStyle = UIActivityIndicatorViewStyle.gray;
    view.addSubview(activityIndicator);

    activityIndicator.startAnimating();
    UIApplication.shared.beginIgnoringInteractionEvents();

}

func stopLoading(){ 

    activityIndicator.stopAnimating();
    UIApplication.shared.endIgnoringInteractionEvents();

}