使用CLLocationCoordinate2D填充malloc-ed数组 [英] Populating malloc-ed array with CLLocationCoordinate2D

问题描述

到目前为止，我对Objective-C和Cocoa框架留下了深刻的印象，但我不得不说，我有点困惑的最好的方式来创建一个CLLocationCoordinate2D数组传递给polylineWithCoordinates：count：I pretty pretty确保这是我需要设置数组。

So far I have been very impressed with Objective-C and the Cocoa Frameworks but I have to say that I am a little confused by the best way to create an array of CLLocationCoordinate2D to pass to the polylineWithCoordinates:count: I am pretty sure that this is how I need to setup the array.

NSUInteger numPoints = [locationData count]; 
CLLocationCoordinate2D *arrayPtr = malloc(numPoints * sizeof(CLLocationCoordinate2D));

但我不知道如何访问每个位置，我想我可以使用arrayPtr [i]

But I am not sure how to access each location, I thought I could use arrayPtr[i] but I can't seem to get that to work properly.

for(NSUInteger counter=0; counter<numPoints; counter++) {
    arrayPtr[counter] = [[locationData objectAtIndex:counter] coordinate];
}

EDIT：

我现在工作，现在，我正在查看内存错误在调试器，但有另一种方式（也许没有malloc）我尝试编码的值在NSArray使用NSValue，只是发现我需要一个c型数组

I have it working now, I was viewing the memory wrong in the debugger, but is there another way (maybe without malloc) I did try encoding the values in an NSArray using NSValue, only to find that I need a c-type array instead :( any alternative methods would be most welcome.

推荐答案

这应该是有效的 - 你得到什么错误？

That should be valid - what error are you getting?

一个更好的方法可能是使用CFArray而不是手动管理malloc。

A better approach might be to use CFArray instead of manually managing the malloc.

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