我遇到了 ALAsset 库的问题：我有一个包含 100 个图像视图的 UIView。加载视图时，我正在调用一个用于从文件名生成图像的函数。
这是我的课：
@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
}
这是我发现问题的方法：
- (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;
}
问题是当我第一次加载视图时，资产库图像没有生成，只显示捆绑图像，如果我转到另一个视图中的任何一个并返回到 100 个图像视图，则生成资产图像。并且可以工作美好的。问题是相同的功能在第一次加载时不会生成资产图像。我怎样才能解决这个问题？提前致谢。