#import <UIKit/UIKit.h>@interface AlertView : UIView@property (strong, nonatomic) UILabel *messageLabel;@end

#import "AlertView.h"@interface AlertView(){    UIActivityIndicatorView *activityIndicatorView;}@end@implementation AlertView@synthesize messageLabel;-(id) init{    CGRect viewRect = CGRectMake(0, 0, 120, 120);    self = [super initWithFrame:viewRect];        if (self) {        [self initSetup];        [self initActivityIndicatorView];        [self initMessage];    }    return self;}-(void) initSetup{    CGRect mainRect = [[UIScreen mainScreen] bounds];    self.backgroundColor = [UIColor blackColor];    self.center = CGPointMake(mainRect.size.width / 2, mainRect.size.height / 2);    self.alpha = 0.6;    [[self layer] setCornerRadius: 15.0];}-(void) initActivityIndicatorView{    CGRect frameRect = self.frame;    activityIndicatorView = [[UIActivityIndicatorView alloc]                             initWithActivityIndicatorStyle:UIActivityIndicatorViewStyleWhiteLarge];    activityIndicatorView.center = CGPointMake(frameRect.size.width / 2, frameRect.size.height / 2 - 10);    [self addSubview:activityIndicatorView];    [activityIndicatorView startAnimating];}-(void) initMessage{    messageLabel = [[UILabel alloc]init];    messageLabel.frame = CGRectMake(0, 0, self.frame.size.width - 15, 20);    messageLabel.font = [UIFont fontWithName:@"Arial-Bold" size:15];    messageLabel.textColor = [UIColor whiteColor];    messageLabel.center =  CGPointMake(self.frame.size.width / 2, self.frame.size.height -20);    messageLabel.text = @"Please Wait...";    [self addSubview:messageLabel];}@end

#import "ViewController.h"#import "AlertView.h"@interface ViewController (){    AlertView *alertView;}@end@implementation ViewController- (void)viewDidLoad{    [super viewDidLoad];    alertView = nil;}-(void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event{    if (alertView) {        [alertView removeFromSuperview];        alertView = nil;    }    else    {        alertView = [[AlertView alloc]init];        [self.view addSubview:alertView];    }}