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Swift/iOS: How to access Object properties when type-casted from Protocol?


Swift/iOS: How to access Object properties when type-casted from Protocol?

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Swift/iOS: How to access Object properties when type-casted from Protocol?
Tag : swift , By : nabbed
Date : November 29 2020, 01:01 AM

I think the issue was by ths following , The following post will help you better understand the issue
https://www.lesstroud.com/dynamic-dispatch-with-nsmanaged-in-swift/

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Access associated type of a custom protocol in a where clause on generic types in Swift


Tag : generics , By : Pierre LeBoo
Date : March 29 2020, 07:55 AM
will help you The problem is that you're using the reserved word Type. Try it with some other name like HashType and it compiles fine.
See "Metatype Type" from the Swift Programming Language:

Can I cast a metaclass object to a protocol type in Swift?


Tag : swift , By : Angel Paunchev
Date : March 29 2020, 07:55 AM
it fixes the issue As of Xcode 7 beta 2 and Swift 2 it has been fixed. You can now write:
for type in types {
    if let fooType = type as? Foo.Type {
        // in Swift 2 you have to explicitly call the initializer of metatypes
        let obj = fooType.init(foo: "special snowflake string")
    }
}
for case let type as Foo.Type in types {
    let obj = type.init(foo: "special snowflake string")
}

In swift, how do I return an object of the same type that conforms to a protocol


Tag : swift , By : Adil
Date : March 29 2020, 07:55 AM
around this issue Autocomplete will help you, but basically, if Foo is a class, you just need a method which matches the exact signature of the method in your protocol:
class Foo {}

protocol JSONInitializable {
    static func initialize(fromJSON: [String : AnyObject]) throws -> Self?
}

extension Foo: JSONInitializable {
    static func initialize(fromJSON: [String : AnyObject]) throws -> Self? {
        return nil
    }
}
struct Foo: JSONInitializable {
    static func initialize(fromJSON: [String : AnyObject]) throws -> Foo? {
        return nil
    }
}
enum Foo: JSONInitializable {
    case One, Two, Three

    static func initialize(fromJSON: [String : AnyObject]) throws -> Foo? {
        return nil
    }
}

How to make a swift class conform to a protocol that requires a protocol-conform type for one of its properties?


Tag : swift , By : wrb302
Date : March 29 2020, 07:55 AM
I hope this helps you . You can do this with associated types.
Declare an associated type in ProtocolA:
protocol ProtocolA {
    associatedtype BType: ProtocolB
    var b: BType? { get } // Note the change in the type of b
}
extension A: ProtocolA {
    typealias BType = B
}
var protocolA: ProtocolA? // error

Swift cast object to type and protocol at the same time


Tag : ios , By : Alan Little
Date : March 29 2020, 07:55 AM
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