带有 malloc'd 结构的 NSMutableArray addobject [英] NSMutableArray addobject with malloc'd struct

问题描述

我在处理一段代码时遇到了问题.我正在尝试使用 addObject 方法将 CLLocationCoordinate2D 的实例添加到 NSMutable 数组，但是每当执行该行时，我的应用程序就会崩溃.这段代码有什么明显的错误吗?

I'm having trouble with a snippet of code. I'm trying to add an instance of CLLocationCoordinate2D to a NSMutable array using the addObject method, but whenever the line is executed, my app crashes. Is there anything obvious wrong with this code?

崩溃就在这条线上:

[points addObject:(id)new_coordinate];

多边形.m:

#import "Polygon.h"

@implementation Polygon
@synthesize points;

- (id)init {
    self = [super init];
    if(self) {
        points = [[NSMutableArray alloc] init];
    }
    return self;
}


-(void)addPointLatitude:(double)latitude Longitude:(double)longitude {
    NSLog(@"Adding Coordinate: [%f, %f] %d", latitude, longitude, [points count]);
    CLLocationCoordinate2D* new_coordinate = malloc(sizeof(CLLocationCoordinate2D));
    new_coordinate->latitude = latitude;
    new_coordinate->longitude = longitude;
    [points addObject:(id)new_coordinate];
    NSLog(@"%d", [points count]);
}


-(bool)pointInPolygon:(CLLocationCoordinate2D*) p {
    return true;
}


-(CLLocationCoordinate2D*) getNEBounds {
    ...
}

-(CLLocationCoordinate2D*) getSWBounds {
    ...
}


-(void) dealloc {
    for(int count = 0; count < [points count]; count++) {
        free([points objectAtIndex:count]);
    }

    [points release];
    [super dealloc];
}

@end

推荐答案

正确的做法是将数据封装在一个 NSValue 中，专门用于将 C 类型放入 NSArrays 和其他集合.

The proper way to do this is to encapsulate the data inside a NSValue, which is specifically for putting C types in NSArrays and other collections.

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