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I am using the Xcode beta for developers, and am noticing some subtle differences. Among them is a new attribute for declared properties.
@property(strong)IBOutlet NSArrayController *arrayControl; My question is: what does the strong attribute mean?? Does it replace some older one, or is it something entirely new? I have searched through google and the developer documentation and havent been able to find anything. Until i know what it is i am hesitant to use it.
Thanks in advance
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1. When we declare weak property then it only contains data/instance address till strong reference is in memory if strong variable reference deallocated it is automatically set to nil. For ex:- var str = "hello world" weak var stringVar = str.
Nonatomic means multiple thread access the variable (dynamic type). Nonatomic is thread unsafe. But it is fast in performance. Nonatomic is NOT default behavior; we need to add nonatomic keyword in property attribute.
assign(to:on:)Assigns each element from a publisher to a property on an object. iOS 13.0+ iPadOS 13.0+ macOS 10.15+ Mac Catalyst 13.0+ tvOS 13.0+ watchOS 6.0+
It's a replacement for the retain attribute, as part of Objective-C Automated Reference Counting (ARC). In non-ARC code it's just a synonym for retain.
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A strong reference is a reference to an object that stops it from being deallocated. In other words it creates a owner relationship. Whereas previously you would do this:
**// Non-ARC Compliant Declaration @property(retain) NSObject *obj;** Under ARC we do the following to ensure a class instance takes an ownership interest a referenced object (i.e. so it cannot be deallocated until the owner is).
**// ARC Compliant Declaration @property(strong) NSObject *obj;** If you love us? You can donate to us via Paypal or buy me a coffee so we can maintain and grow! Thank you!
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