MBProgressHUD not updating progress - ios

Question

I am importing multiple photos from photos library and I want to show the progress using MBProgressHUD. I am using QBImagePickerController to import photos. My photos are imported successfully. However the progress bar in MBProgressHUD is not updating. The following is my code
-(void)qb_imagePickerController:(QBImagePickerController *)imagePickerController didSelectAssets:(NSArray *)assets {
if (imagePickerController.filterType == QBImagePickerControllerFilterTypePhotos) {
MBProgressHUD *hud = [MBProgressHUD showHUDAddedTo:self.navigationController.view animated:YES];]
// Set the determinate mode to show task progress.
hud.mode = MBProgressHUDModeDeterminateHorizontalBar;
hud.delegate = self;
hud.labelText = NSLocalizedString(#"Importing Photos", nil);
hud.dimBackground = YES;
hud.detailsLabelFont = [UIFont systemFontOfSize:12.0f];
hud.detailsLabelText = NSLocalizedString(#"Please wait...", nil);
hud.progress = 0.0f;
[self importPhotosForArray:assets];
}
[self dismissImagePickerController];
}
- (void) importPhotosForArray:(NSArray *)info {
for (ALAsset *selectedImageAsset in info) {
ALAssetsLibrary *assetsLibrary = [[ALAssetsLibrary alloc] init];
[assetsLibrary assetForURL:[selectedImageAsset defaultRepresentation].url resultBlock: ^(ALAsset *asset){
ALAssetRepresentation *representation = [asset defaultRepresentation];
CGImageRef imageRef = [representation fullResolutionImage];
if (imageRef) {
UIImage *image = [UIImage imageWithCGImage:imageRef];
NSData *imageData = UIImageJPEGRepresentation(image, 1.0);
// Create a file name for the image
NSDateFormatter *dateFormatter = [[NSDateFormatter alloc] init];
[dateFormatter setTimeStyle:NSDateFormatterMediumStyle];
[dateFormatter setDateStyle:NSDateFormatterMediumStyle];
NSString *imageName = [NSString stringWithFormat:#"photo-%#.png", [dateFormatter stringFromDate:[NSDate date]]];
// Now we get the full path to the file
NSString *fullPathToFile = [self.folder.fullPath stringByAppendingPathComponent:imageName];
// Write out the data.
[imageData writeToFile:fullPathToFile atomically:NO];
sleep(1.0);
progress = ++index/[info count];
[MBProgressHUD HUDForView:self.navigationController.view].progress = progress;
if (progress >= 1.0) {
[[MBProgressHUD HUDForView:self.navigationController.view] hide:YES];
[self reloadData];
}
}
} failureBlock: ^(NSError *error){
// Handle failure.
NSLog(#"Failure");
}];
}
}

Answer 1

declare MBProgressHUD As property and use it every where.
#property (nonatomic, strong) MBProgressHUD *hud;
-(void)qb_imagePickerController:(QBImagePickerController *)imagePickerController didSelectAssets:(NSArray *)assets {
if (imagePickerController.filterType == QBImagePickerControllerFilterTypePhotos) {
self.hud = [MBProgressHUD showHUDAddedTo:self.navigationController.view animated:YES];]
// Set the determinate mode to show task progress.
self.hud.mode = MBProgressHUDModeDeterminateHorizontalBar;
self.hud.delegate = self;
self.hud.labelText = NSLocalizedString(#"Importing Photos", nil);
self.hud.dimBackground = YES;
self.hud.detailsLabelFont = [UIFont systemFontOfSize:12.0f];
self.hud.detailsLabelText = NSLocalizedString(#"Please wait...", nil);
self.hud.progress = 0.0f;
[self importPhotosForArray:assets];
}
[self dismissImagePickerController];
}
- (void) importPhotosForArray:(NSArray *)info {
for (ALAsset *selectedImageAsset in info) {
ALAssetsLibrary *assetsLibrary = [[ALAssetsLibrary alloc] init];
[assetsLibrary assetForURL:[selectedImageAsset defaultRepresentation].url resultBlock: ^(ALAsset *asset){
ALAssetRepresentation *representation = [asset defaultRepresentation];
CGImageRef imageRef = [representation fullResolutionImage];
if (imageRef) {
UIImage *image = [UIImage imageWithCGImage:imageRef];
NSData *imageData = UIImageJPEGRepresentation(image, 1.0);
// Create a file name for the image
NSDateFormatter *dateFormatter = [[NSDateFormatter alloc] init];
[dateFormatter setTimeStyle:NSDateFormatterMediumStyle];
[dateFormatter setDateStyle:NSDateFormatterMediumStyle];
NSString *imageName = [NSString stringWithFormat:#"photo-%#.png", [dateFormatter stringFromDate:[NSDate date]]];
// Now we get the full path to the file
NSString *fullPathToFile = [self.folder.fullPath stringByAppendingPathComponent:imageName];
// Write out the data.
[imageData writeToFile:fullPathToFile atomically:NO];
sleep(1.0);
progress = ++index/[info count];
self.hud.progress = progress;
if (progress >= 1.0) {
[MBProgressHUD hideAllHUDsForView:self.navigationController.view animated:YES];
[self reloadData];
}
}
} failureBlock: ^(NSError *error){
// Handle failure.
NSLog(#"Failure");
}];
}
}
Try this
Because as per your code when u update progress every time new object of MBProgressHUD get and update

Answer 2

UI updates (i.e. changes to the progress bar) must be made on the main thread or you may suffer from unpredictable side effects.
The user interface element may not be redrawn after your property changes
I believe that ALAssetsLibrary.assetForURL is automatically happening in a background thread. To get around that you want to use a solution that lets you run the UI updates on the main thread. In this case your UI updates would be this line
[MBProgressHUD HUDForView:self.navigationController.view].progress = progress;
so try something like this:
dispatch_async(dispatch_get_main_queue(), ^{
[MBProgressHUD HUDForView:self.navigationController.view].progress = progress;
});
Also, you should verify that ++index/[info count] is actually increasing as you expect it to by printing the value out each time index updates.

Answer 3

Try this code. Replace your importPhotosForArray method with the following.
- (void) importPhotosForArray:(NSArray *)info {
dispatch_async(dispatch_get_global_queue(QOS_CLASS_USER_INITIATED, 0), ^{
__block float progress = 0.0f;
__block float index = 0.0f;
for (ALAsset *selectedImageAsset in info) {
ALAssetRepresentation *representation = [selectedImageAsset defaultRepresentation];
CGImageRef imageRef = [representation fullResolutionImage];
if (imageRef) {
UIImage *image = [UIImage imageWithCGImage:imageRef];
NSData *imageData = UIImagePNGRepresentation(image);
// Create a file name for the image
NSDateFormatter *dateFormatter = [[NSDateFormatter alloc] init];
[dateFormatter setTimeStyle:NSDateFormatterMediumStyle];
[dateFormatter setDateStyle:NSDateFormatterMediumStyle];
NSString *imageName = [NSString stringWithFormat:#"photo-%#.png", [dateFormatter stringFromDate:[NSDate date]]];
// Now we get the full path to the file
NSString *fullPathToFile = [self.folder.fullPath stringByAppendingPathComponent:imageName];
// Write out the data.
[imageData writeToFile:fullPathToFile atomically:YES];
sleep(1);
progress = ++index/[info count];
dispatch_async(dispatch_get_main_queue(), ^{
// Instead we could have also passed a reference to the HUD
// to the HUD to myProgressTask as a method parameter.
[MBProgressHUD HUDForView:self.navigationController.view].progress = progress;
});
if (progress >= 1.0) {
dispatch_async(dispatch_get_main_queue(), ^{
// Instead we could have also passed a reference to the HUD
// to the HUD to myProgressTask as a method parameter.
[[MBProgressHUD HUDForView:self.navigationController.view] hide:YES];
[self reloadData];
});
}
}
}
});
}