SDWebImage Class - iphone

Question

How can I use this method to perform activity indicator in placeholder ?
- (void)createActivityIndicatorWithStyle:(UIActivityIndicatorViewStyle) activityStyle {
if ([self activityIndicator] == nil) {
self.activityIndicator = [[UIActivityIndicatorView alloc] initWithActivityIndicatorStyle:activityStyle];
self.activityIndicator.autoresizingMask = UIViewAutoresizingNone;
//calculate the correct position
float width = self.activityIndicator.frame.size.width;
float height = self.activityIndicator.frame.size.height;
float x = (self.frame.size.width / 2.0) - width/2;
float y = (self.frame.size.height / 2.0) - height/2;
self.activityIndicator.frame = CGRectMake(x, y, width, height);
self.activityIndicator.hidesWhenStopped = YES;
[self addSubview:self.activityIndicator];
}
[self.activityIndicator startAnimating];
}
I appreciate any help

Answer 1

You can do it this way, i use it in this example for updating cells, but it is the same for any use you need.
What i'm doing is setting the UIImageView alpha to 0,Adding a UIActivityIndicatore,and calling a block to get notified when the image has bees loaded.
When its loaded, the UIImageView alpha will be set back to 1, and remove the UIActivityIndicator.
-(void)updateCell {
self.imageView = [[UIImageView alloc]initWithFrame:frameOfCell];
self.imageView.alpha = 0;
[self addSubview:self.imageView];
//Activity indivator:
self.activity= [[UIActivityIndicatorView alloc]initWithActivityIndicatorStyle:UIActivityIndicatorViewStyleWhiteLarge];
self.activity.hidesWhenStopped = YES;
self.activity.frame = CGRectMake((frameOfCell.size.width/2)-10, (frameOfCell.size.height/2)-20, 40, 40);
[self.activity startAnimating];
[self addSubview:self.activity];
[self.imageView setContentMode:UIViewContentModeScaleAspectFit];
NSURL *urlOfImage = [NSURL URLWithString:self.imageName];
self.imageView.alpha = 0;
[self.imageView setImageWithURL:urlOfImage completed:^(UIImage *image, NSError *error, SDImageCacheType cacheType) {
///
self.imageView.alpha = 1;
//Removing activity indicator:
[self.activity stopAnimating];
[self.activity removeFromSuperview];
}];
}
Hope this helps

Answer 2

Here is a Category on UIImageView, adding a progress view while images are downloaded using SDWebImage.
What you should to do is to change UIProgressView with UIActivityIndicatorView
Try to modify code like this:
- (void)removeIndicatorView{
[self.activityIndicator stopAnimating];
}
- (void)setImageWithURL:(NSURL *)url placeholderImage:(UIImage *)placeholder options:(SDWebImageOptions)options completed:(SDWebImageCompletedBlock)completedBlock withActivityStyle:(UIActivityIndicatorViewStyle) activityStyle {
[self createActivityIndicatorWithStyle:activityStyle];
__weak typeof(self) weakSelf = self;
[self setImageWithURL:url
placeholderImage:placeholder
options:options
progress:^(NSUInteger receivedSize, long long expectedSize) {
//If you don't care progress, do nothing
}
completed:^(UIImage *image, NSError *error, SDImageCacheType cacheType) {
[weakSelf removeIndicatorView];
if (completedBlock) {
completedBlock(image, error, cacheType);
}
}
];
}