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Larry Mc Goldrick
4,131 PointsXCode/Objective-C
Hi I have been trying to get my head around Xcode & Objective-C and have seen a few sample codes where (associated with Getters & Setters) the name of the property in the code changes from e.g: example to _example . Can anyone explain why this is?
Thanks Larry
2 Answers
Shehryar Khan
Courses Plus Student 7,520 PointsThis is just a naming convention. As of the latest version of Xcode, properties autosynthesize instance variables prefixed with an underscore:
@property (nonatomic, strong) NSString *myProp --> ivar = _myProp
In previous versions, properties automatically created instance variables with the same name as the property. The change was done to prevent users from inadvertently modifying an instance variable without going through its getter/setter. For reasons such as memory implications, you should always access an instance variable via its property.
If you @synthesize a property named myProp and try to access it via "myProp", you will get a compiler error. You need to access it either via it's property (self.myProp) or it's instance variable directly (_myProp)
Chad Shores
Courses Plus Student 8,868 Pointsconventions