Objective C read-only int? What?
I made an int to count how many suc开发者_开发问答cesses one of my processes has. Outside my code, I declare:
int successes = 0
.
Then within my loop, I have successes++;
, at which point XCode complains that "variable is not assignable (missing _block type specifier)".
What is going on? Why can't I increment my int? I never declared it read-only...
Any help is much appreciated.
The code I used is:
_block int successes = 0;
for(CLLocation *location in locationOutputArray)
{
CLGeocoder *geocoder = [[CLGeocoder alloc] init];
[geocoder reverseGeocodeLocation:location completionHandler:^(NSArray *placemarks, NSError *error)
{
if(placemarks && placemarks.count > 0)
{
successes++;
CLPlacemark *topResult = [placemarks objectAtIndex:0];
NSString *address = [NSString stringWithFormat:@"%@ %@,%@ %@", [topResult subThoroughfare],[topResult thoroughfare],[topResult locality], [topResult administrativeArea]];
[addressOutputArray addObject:address];
NSLog(@"%@",address);
}
}];
[geocoder release];
}
Your loop is inside a block (^{...}
syntax). Blocks cannot alter variables outside of the block without that variable having a __block
specifier.
You tried accessing this int
inside a block. Mark it as __block
so it can be updated from within the block.
Blocks Programming Topics
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