Out of scope CGFloat array

Question

I want to use a C-style CGFloat array defined in the didMoveToView method in the touchesBegan method. I can't seem to define it as a property because it is a CGFloat array. Globals don't seem to work either. My array is defined like this:

CGFloat levelMapX[] = {self.frame.size.width/2 ...};

I am using SpriteKit.

What about an instance variable? – rmaddy Dec 21 '14 at 19:35 — rmaddy, Dec 21 '14 at 19:35
That should compile. Post the entire method. – EricS Dec 21 '14 at 20:11 — EricS, Dec 21 '14 at 20:11

score 0 · Answer 1 · edited May 23 '17 at 10:26

0

You can declare a pointer to a CGFloat. Although arrays and pointers are not the same in C, they can often be used in a similar way.

@property (assign, nonatomic) CGFloat* array;

And then use it like an array:

const NSInteger myArraySize = 10 * sizeof(CGFloat);
self.array = malloc(myArraySize);
self.array[0] = 0.42;
self.array[1] = M_PI;

remember to free it so you don't leak memory:

- (void)dealloc {
    free(self.array);
}

edited May 23 '17 at 10:26

Community

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answered Dec 21 '14 at 19:43

Michał Ciuba

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freeing it made the app crash, I'm not sure why – Red Badger Dec 21 '14 at 23:18
The code should actually read `const NSInteger myArraySize = 10 * sizeof(CGFloat);`, where 10 is the number of `CGFloat`s. `malloc` uses size which are in bytes. – Mobile Ben Dec 22 '14 at 00:41
@RedBadger how did you initialize `self.array`? I tested it and `free` didn't crash. – Michał Ciuba Dec 22 '14 at 08:32

Out of scope CGFloat array

1 Answers1