When does dealloc is called

After performing the class-specific deallocation, the subclass method should incorporate superclass versions of dealloc through a message to super:. For this and other reasons, you should not manage scarce resources in dealloc. I'm sure it's a little more complicated than that, but the answer to your question is that the object itself will call -dealloc when its retain count drops to zero.

However, your custom class will inherit this behavior from NSObject. You'll never need to call -dealloc yourself in code that you write; it'll always happen automatically when the object has been properly released. You can use nil about anywhere you can use null. The main difference is that you can send messages to nil , so you can use it in some places where null cant work. The effect of a further method calls through this pointer is one of these three which one is undefined :.

Now the object reference is nil and any further method calls are ignored. This may silently cause a defined but unforeseen lateral effect in your code, but at least it doesn't crash your application. This is the same as before, but it removes that small window between release and nil where the object reference points to an invalid object. A easy way to defer your choice is using a macro. Instead [airplane release] you write safeRelease x where safeRelease is the following macro that you add to your.

This macro doesn't respect zombies. If you nil its object reference, any call sent to him will be ignored. This guarantees a crash during debug time if zombies are not enabled, but leaves the zombies be otherwise. Code Revisions 2 Stars 2.

Embed What would you like to do? Embed Embed this gist in your website. Share Copy sharable link for this gist. Learn more about clone URLs. Download ZIP. Found this in some code This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters. Learn more about bidirectional Unicode characters. This comment has been minimized. Is setting to nil after releasing advantageous?

I use code like the following inside my appController. Thank you In Objective-C, I understand that if an object sets itself as the delegate of another object, it should set that object's delegate to nil in its What is the purpose of that? I'm new to Objective-C and stackoverflow and I'm a little turned around about best practices with regards to properties.

My understanding is that I know declared property generates accessor method which is someway just syntax sugar. I found quite a lot people use self.