NSMutableArray addobject with malloc'd struct [英] NSMutableArray addobject with malloc'd struct

问题描述

我遇到了一段代码的问题。我试图使用addObject方法添加一个CLLocationCoordinate2D的实例到NSMutable数组，但每当该行执行，我的应用程序崩溃。这个代码有什么明显的错误吗？

崩溃是在这一行：

 code> [points addObject：（id）new_coordinate]; 
  

Polygon.m：

  #importPolygon.h
 
 @implementation多边形
 @synthesize points; 
 
  - （id）init {
 self = [super init]; 
 if（self）{
 points = [[NSMutableArray alloc] init]; 
} 
 return self; 
} 
 
 
  - （void）addPointLatitude：（double）latitude经度：（double）longitude {
 NSLog（@添加坐标：[％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 
  

解决方案>

正确的方法是将数据封装在 NSValue 中，这是专门用于将 NSArray s和其他集合。

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?

The crash is on this line:

[points addObject:(id)new_coordinate];

Polygon.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

解决方案

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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