issue with AlAsset library - iphone

Question

I'm facing an issue with the ALAsset library: I have an UIView with 100 image views. When the view is loading, i'm calling a function for generating the images from the file name.
This is my class:
#interface myClass
{
NSString *fileName;
int pathId;
}
viewDidLoad
-(void)viewDidLoad
{
NSMutableArray *imageCollectionArray = [self createImage:arrayOfmyClassObject];
//Here I'm binding the 100 images in UIView using the images in imageCollectionArray
}
This is my method in which I found the issue:
- (NSMutableArray *)createImage:(NSMutableArray *)imageFileNamesArray
{
imageArray = [[NSMutableArray alloc] init];
for (int imageNameKey = 0; imageNameKey<100; imageNameKey++)
{
myClass *obj= [imageFileNamesArray objectAtIndex:imageNameKey];
if(obj.pathId == 0)
{
//Here adding the bundle image into the imageArray
[imageArray addObject:[UIImage imageWithContentsOfFile:[[NSBundle mainBundle] pathForResource:obj.fileName ofType:#"png" inDirectory:#"Images"]]];
}
else
{
typedef void (^ALAssetsLibraryAssetForURLResultBlock)(ALAsset *asset); typedef void (^ALAssetsLibraryAccessFailureBlock)(NSError *error);
ALAssetsLibraryAssetForURLResultBlock resultblock = ^(ALAsset *myasset) {
};
ALAssetRepresentation *rep = [myasset defaultRepresentation];
CGImageRef iref = [rep fullResolutionImage];
UIImage *images;
if (iref)
{
//Here adding the photo library image into the imageArray
images = [UIImage imageWithCGImage:iref];
[imageArray addObject:images];
}
else
{
//Here adding the Nofile.png image into the imageArray if didn't find a photo library image
images = [UIImage imageNamed:#"Nofile.png"];
[imageArray addObject:images];
}
ALAssetsLibraryAccessFailureBlock failureblock = ^(NSError *myerror) {
//Here adding the Nofile.png image into the imageArray if any failure occurs
[imageArray addObject:[UIImage imageNamed:#"Nofile.png"]];
NSLog(#"booya, cant get image - %#",[myerror localizedDescription]);
};
NSURL *asseturl = [NSURL URLWithString:obj.fileName];
ALAssetsLibrary* assetslibrary = [[[ALAssetsLibrary alloc] init] autorelease];
[assetslibrary assetForURL:asseturl
resultBlock:resultblock failureBlock:failureblock];
}
}
return imageArray;
}
The problem was when I loads the view at first time the asset library images are not generating, only bundle images were displayed, if i go to any of the another view and return back to 100 image view then the asset images are generated.And works fine. The problem is the same function is not generating asset images at the first load. How can i fix this? Thanks in advance.

Answer 1

All methods related to ALAssetLibrary are asynchronous, so your view may complete its loading life cycle before the desired data is returned. You have to take this into account and redraw your view (or a portion of it) as needed.