在NSMutableArray中存储CLLocationCoordinates2D

Question

经过一番搜索,我得到了以下解决方案: 参考.

CLLocationCoordinate2D* new_coordinate = malloc(sizeof(CLLocationCoordinate2D));
new_coordinate->latitude = latitude;
new_coordinate->longitude = longitude;
[points addObject:[NSData dataWithBytes:(void *)new_coordinate
length:sizeof(CLLocationCoordinate2D)]];
free(new_coordinate);

并将其访问为:

CLLocationCoordinate2D* c = (CLLocationCoordinate2D*) [[points objectAtIndex:0] bytes];

但是,有人声称这里有内存泄漏？任何人都可以建议我在哪里泄漏以及如何解决它.此外,是否有更好的方法在NSMutableArray中存储CLLocationCoordinate2D列表？请提供示例代码,因为我是Objective C新手.

Answer 1

这是另一种方法,使用NSValue为此目的而构建的内置类型:

CLLocationCoordinate2D new_coordinate = { latitude, longitude };
[points addObject:[NSValue valueWithBytes:&new_coordinate objCType:@encode(CLLocationCoordinate2D)]];

要检索该值,请使用以下代码:

CLLocationCoordinate2D old_coordinate;
[[points objectAtIndex:0] getValue:&old_coordinate];

Answer 2

从iOS 6开始,NSValueMapKitGeometryExtensions用于NSValue:

NSMutableArray *points = [NSMutableArray array];
CLLocationCoordinate2D new_coordinate = CLLocationCoordinate2DMake(latitude, longitude);
[points addObject:[NSValue valueWithMKCoordinate:new_coordinate]];

并检索值:

CLLocationCoordinate2D coordinate = [[points objectAtIndex:0] MKCoordinateValue];

该NSValueMapKitGeometryExtensions要求MapKit.framework
CLLocationCoordinate2DMake()需要CoreLocation.framework

Answer 3

没有泄漏,只是浪费堆内存.

你可以使用

CLLocationCoordinate2D new_coordinate;
new_coordinate.latitude = latitude;
new_coordinate.longitude = longitude;
[points addObject:[NSData dataWithBytes:&new_coordinate length:sizeof(new_coordinate)]];