When should I access properties with self in swift?

Question

In a simple example like this, I can omit self for referencing backgroundLayer because it\'s unambiguous which backgroundLayer the backgroundColor is set on.

Answer 1

Most of the time we can skip self. when we access class properties.

1. However there is one time when we MUST use it: when we try to set self.property in a closure:

   dispatch_async(dispatch_get_main_queue(), {
       // we cannot assign to properties of self
       self.view = nil 
   
       // but can access properties
       someFunc(view)
   })
   

2. one time when we SHOULD use it: so you don't mess a local variable with class property:

   class MyClass {
       var someVar: String = "class prop"
   
       func setProperty(someVar:String = "method attribute") -> () {
           print(self.someVar) // Output: class property
           print(someVar) // Output: method attribute
       }
   }
   

3. other places where we CAN use self. before property just to be expressive about were variable/constant comes from.