Block implicitly retains 'self'; explicitly mention 'self' to indicate this is intended behavior
macos, objective-c, objective-c-blocks
Solution
Replacing `myTimer` by `self->myTimer` would fix your warning.
When you use an iVar `_iVar` in the code, the compiler will replace the code by `self->_iVar`, and if you use it inside a block, the block will capture self instead of the iVar itself. The warning is just to make sure that the developer understand this behaviour.
Problem
Given the following: ``` - (void) someMethod { dispatch_async(dispatch_get_main_queue(), ^{ myTimer = [NSTimer scheduledTimerWithTimeInterval: 60 target: self selector: @selector(doSomething) userInfo: nil repeats: NO]; }); } ``` Where myTimer is declared in a private interface: ``` @interface MyClass() { NSTimer * myTimer; } @end ``` How would one fix the following warning: ``` Block implicitly retains 'self'; explicitly mention 'self' to indicate this is intended behavior ``` From what I have found so far, most suggestions involve putting something such as: ``` - (void) someMethod { __typeof__(self) __weak wself = self; dispatch_async(dispatch_get_main_queue(), ^{ wself.myTimer = [NSTimer scheduledTimerWithTimeInterval: 60 target: self selector: @selector(doSomething) userInfo: nil repeats: NO]; }); } ``` Except, that myTimer is an ivar, meaning `wself` does not have access to any properties. I guess my questions are: - Do/should I care? - Should I declare myTimer as a property? I use ivars quite a bit through my code. I just added the `-Weverything` flag to my project to see if I can find any underlying issues and this is by far the most common warning. I have no problem going though and fixing it by making my ivars properties, but I want to make sure I get a better understanding before I do that.