Question

is this OK practice?

NSArray* myarray[3] = {nil,nil,nil}

...

myarray[0] = some NSArray

or is it better to stick with NSArray over all?

NSArray* myarray = [NSArray...] ?
...
[myarray addObject:..]

Answer 1

Depends on your needs. Either way works, but I generally find that mixing Objective-C objects and C structures leads to madness as you have to maintain sanity over two different memory models; retain/release and malloc/free.

I also generally avoid multi-dimensional arrays entirely. For example, a 3×4 array of arrays can be represented as a single array of 12 items. An item at 2,3 is really at (2 + (3*width)).

Note that NSArrays can’t have “holes”. You can represent the holes, if needed, with NSNull objects. Or create a subclass of NS[Mutable]Array that allows holes.