Access property inside a block objective c - objective-c

Question

- (IBAction)saveBtn:(id)sender {
UIImage* imageToSave = [self imageByCombiningImage:self.backgroundImage.image withImage:self.tempImage.image];
ALAssetsLibrary *library = [[ALAssetsLibrary alloc] init];
// Request to save the image to camera roll
[library writeImageToSavedPhotosAlbum:[imageToSave CGImage] orientation:(ALAssetOrientation)[imageToSave imageOrientation] completionBlock:^(NSURL *assetURL, NSError *error){
if (error) {
NSLog(#"error");
} else {
CGFloat compression = 0.0;
NSData *imageData = UIImageJPEGRepresentation(imageToSave, compression);
UIImage *compressedImage = [[UIImage alloc]initWithData:imageData];
NSMutableString *imageName = [[NSMutableString alloc] initWithCapacity:0];
CFUUIDRef theUUID = CFUUIDCreate(kCFAllocatorDefault);
if (theUUID) {
[imageName appendString:CFBridgingRelease(CFUUIDCreateString(kCFAllocatorDefault, theUUID))];
CFRelease(theUUID);
}
[imageName appendString:#".png"];
NSLog(#"Image name: %#", imageName);
//Image Data to web service
[self uploadImage:UIImageJPEGRepresentation(compressedImage, 1.0) filename:imageName];
_savedImageURL = assetURL;
[library assetForURL:_savedImageURL
resultBlock:resultblock
failureBlock:failureblock];
}];
}
ALAssetsLibraryAssetForURLResultBlock resultblock = ^(ALAsset *myasset)
{
ALAssetRepresentation *rep = [myasset defaultRepresentation];
CGImageRef iref = [rep fullResolutionImage];
if (iref) {
UIImage *largeimage = [UIImage imageWithCGImage:iref];
//image Property needs to be access here
}
};
I cannot access any property inside this block. Like I have made a UIImage property in the .h file but I cannot accessed that in that result block.

Answer 1

If the code you've posted is really the one you're using, then it's defining a variable which references a block. But that variable is not part of your class and you thus cannot reference any instance variables.
Instead, the variable is on the "C top-level", outside any class. You might want to turn it into an instance variable, for example like this:
#interface MyClass : SomeSuperClass
{
// Define an instance variable.
ALAssetsLibraryAssetForURLResultBlock resultblock;
}
#end
#implementation MyClass
- (void)someMethod
{
// Initialize the variable in `init`, `viewDidLoad` or whichever
// method suits you.
resultblock = ^(ALAsset *myasset)
{
ALAssetRepresentation *rep = [myasset defaultRepresentation];
CGImageRef iref = [rep fullResolutionImage];
if (iref) {
UIImage *largeimage = [UIImage imageWithCGImage:iref];
//image Property needs to be access here
}
};
}
#end
You could also use a property instead.

Answer 2

Next solution is you can create block property from whole controller like this:
__block MyViewController *blocksafeSelf = self;
and inside block you can use this property to access:
blocksafeSelf.myProperty;
or call method:
dispatch_async(dispatch_get_main_queue(), ^
[blocksafeSelf processNewMessage:text]
});