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iOS

Posted by Guled A.
Guled A.
10,605 Points

@Property Method: What is 'nonatomic' and 'strong'?

The course for objective-c was very nice, but I did not quite understand what these two parameters in the @property method meant. Could anyone elaborate?

Thank you in advance.

2 Answers

jschlansky
jschlansky
7,229 Points
jschlansky
jschlansky
7,229 Points

The 'nonatomic' property is the opposite of the default 'atomic' property. A variable with the 'nonatomic' property means that the variable is not thread safe. This might sound scary, but it just means that the variable can be accessed from multiple threads at the same time. The 'atomic' property does not allow this, which makes the 'nonatomic' property faster to use.

The 'strong' property replaced the 'retain' property. The 'strong' property is required when the attribute is a pointer to an object, and it will be retained in memory. The opposite of this is the 'weak' property.

Guled A.
Guled A.
10,605 Points

Very good explanation. I understand those concepts now. Thank you for your help.

Stone Preston
Stone Preston
42,016 Points
Stone Preston
Stone Preston
42,016 Points

This page helped explain ARC stuff pretty well for me. It can be kind of hard to understand

Guled A.
Guled A.
10,605 Points

Thank you for the article. It helped a lot.