view based app,
.m
- (void)viewDidLoad {
[super viewDidLoad];
self.locationManager = [[[CLLocationManager alloc] init] autorelease];
self.locationManager.delegate = self;
[[self locationManager] startUpdatingLocation];
}
- (void)locationManager:(CLLocationManager *)manager
didUpdateToLocation:(CLLocation *)newLocation
fromLocation:(CLLocation *)oldLocation {
CurrentLocation = newLocation;
[locationManager stopUpdatingLocation];
myActivity.hidden=YES;
[self reStart];
}
-(void)reStart{
[self checkAndCreateDatabase]; //Sucess
[self readFromDatabase]; //Success if I comment the get distance part
[se开发者_开发技巧lf sort]; //Success
}
-(void) readFromDatabase {
...
CLLocationCoordinate2D cord;
cord.latitude = [[NSString stringWithUTF8String:(char *)sqlite3_column_text(compiledStatement, 2)] doubleValue];
cord.longitude =[[NSString stringWithUTF8String:(char *)sqlite3_column_text(compiledStatement, 3)] doubleValue];
NSDate *today = [NSDate date];
CLLocation *objectLocation = [[CLLocation alloc] initWithCoordinate:cord altitude:1 horizontalAccuracy:1 verticalAccuracy:-1 timestamp:today];
CLLocationDistance distance = [objectLocation getDistanceFrom:CurrentLocation]/1000;
NSLog([NSString stringWithFormat:@"%.0f", distance]);
}
What is wrong?
debugger says:
obj_msgSend
0x912e8688 <+0024> mov 0x20(%edx),%edi
object from database: long: 59.291114 lat: 17.816191
Use distanceFromLocation: instead
Is CurrentLocation
an instance-variable/property? You are setting it directly without an accessor and you are not retaining it. If it is released before you use it in getDistance:
it will cause a crash.
If it is a property use the self.CurrentLocation
to ensure it is retained.
Also, the construction...
NSLog([NSString stringWithFormat:@"%.0f", distance]);
... is risky and redundant. Use...
NSLog(@"%.0f", distance);
... instead.
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