How to add MBProgressHUD while saving the image photolibrary IOS7 - ios

Question

Hi in my application i have the image on UIImageView and i have button called download once user click the download button the image will save to the Photolibrary. Now i want to add the Progressbar for the download to know the user its downloading the image.
I have used the MBProgressHUD for the progress but not able work like i wanted. I want to show once user click the download button like its downloading message with progress once image got downloaded i want to show like image downloaded please tell me how to achieve this one i tired something like that its not working.
My MBProgressHUD code.
- (IBAction)down:(id)sender {
HUD = [[MBProgressHUD alloc] initWithView:self.view];
HUD.labelText = #"downloading...";
HUD.mode = MBProgressHUDModeAnnularDeterminate;
[self.view addSubview:HUD];
[HUD showWhileExecuting:#selector(download) onTarget:self withObject:nil animated:YES];
UIImageWriteToSavedPhotosAlbum(imageview.image, nil, nil, nil);
}
- (void)download {
float progress = 0.0;
while (progress < 1.0) {
progress += 0.01;
HUD.progress = progress;
usleep(50000);
}
}
I have used the above code to achieve but its not working like i wanted please tell me how to achieve this one.
Thanks.

Answer 1

- (IBAction)down:(id)sender {
HUD = [MBProgressHUD showHUDAddedTo:self.view animated:YES];
HUD.mode =MBProgressHUDModeAnnularDeterminate;
NSString *strloadingText = [NSString stringWithFormat:#"Downloading...."];
HUD.labelText = strloadingText;
[HUD show:YES];
[HUD showWhileExecuting:#selector(doSomeFunkyStuff) onTarget:self withObject:nil animated:YES];
}
- (void)doSomeFunkyStuff {
float progress = 0.0;
while (progress < 1.0) {
progress += 0.01;
HUD.progress = progress;
usleep(5000000);
dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_LOW, 0),
^{
// process in background thread
NSString *strloadingText = [NSString stringWithFormat:#"completed"];
HUD.labelText = strloadingText;UIImageWriteToSavedPhotosAlbum(imageview.image, nil, nil, nil);
[HUD hide:YES];
});
}
}

Answer 2

UIImageWriteToSavedPhotosAlbum works on main thread. So, put this function in GCD. Your UI can not update itself when main thread is busy.

Answer 3

Try this:
- (IBAction)down:(id)sender {
...
[HUD showWhileExecuting:#selector(download) onTarget:self withObject:nil animated:YES];
dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_LOW, 0),
^{
// process in background thread
UIImageWriteToSavedPhotosAlbum(imageview.image, nil, nil, nil);
// when finish, dismiss HUD
HUD.hidden = YES;
});
}

Answer 4

you can use https://github.com/samvermette/SVProgressHUD for showing progress bar..If you are downloading image from server then use async call. Like if you are using ASIFormDataRequest request for getting image then use as follow :
[SVProgressHUD showWithStatus:#"Please wait"];
self.view.userInteractionEnabled = NO;
NSURL *url=[NSURL URLWithString:#"your URL request"];
ASIFormDataRequest *request = [ASIFormDataRequest requestWithURL:url];
[request setRequestMethod:#"POST"];
[request setPostValue:xyz forKey:#"abc"];
[request.shouldAttemptPersistentConnection = NO;
request.delegate=self;
request.timeOutSeconds = 10;
[request startAsynchronous];
After this you can call :
-(void)requestFinished:(ASIHTTPRequest *)request
{
NSError *error = [request error];
if (!error)
{
NSString *response = [request responseString];
NSMutableDictionary *responseJSON = [response JSONValue];
[SVProgressHUD dismiss];
self.view.userInteractionEnabled = YES;
UIImageWriteToSavedPhotosAlbum(imageview.image, nil, nil, nil);
}
}
Hope this will help you.