UIView+UIActivityIndicatorForSDWebImage.m

//
//  UIView+UIActivityIndicatorForSDWebImage_h.m
//  Pods
//
//  Created by Rafael Nobre on 07/07/14.
//
//

#import "UIView+UIActivityIndicatorForSDWebImage.h"
#import <objc/runtime.h>

static char TAG_ACTIVITY_INDICATOR;

@implementation UIView (UIActivityIndicatorForSDWebImage)

@dynamic activityIndicator;

- (UIActivityIndicatorView *)activityIndicator {
    return (UIActivityIndicatorView *)objc_getAssociatedObject(self, &TAG_ACTIVITY_INDICATOR);
}

- (void)setActivityIndicator:(UIActivityIndicatorView *)activityIndicator {
    objc_setAssociatedObject(self, &TAG_ACTIVITY_INDICATOR, activityIndicator, OBJC_ASSOCIATION_RETAIN);
}

- (void)addActivityIndicatorWithStyle:(UIActivityIndicatorViewStyle) activityStyle {
    
    if (!self.activityIndicator) {
        self.activityIndicator = [[UIActivityIndicatorView alloc] initWithActivityIndicatorStyle:activityStyle];
        
        self.activityIndicator.autoresizingMask = UIViewAutoresizingNone;
        
        dispatch_async(dispatch_get_main_queue(), ^(void) {
            [self addSubview:self.activityIndicator];
            [self updateActivityIndicatorPosition];
        });
    }
    
    dispatch_async(dispatch_get_main_queue(), ^(void) {
        [self.activityIndicator startAnimating];
    });
    
}

-(void)updateActivityIndicatorPosition {
    if (self.activityIndicator) {
        self.activityIndicator.center = CGPointMake((CGRectGetWidth(self.frame) / 2.0f), (CGRectGetHeight(self.frame) / 2.0));
    }
}

- (void)removeActivityIndicator {
    if (self.activityIndicator) {
        [self.activityIndicator removeFromSuperview];
        self.activityIndicator = nil;
    }
}

@end