CODEWITHSUNDEEP
iosswift
André Fratelli
André Fratelli

Reputation: 6068

Type MCSessionState does not conform to protocol 'AnyObject'

I'm getting this error with the following code:

var dict: Dictionary<String, AnyObject> = [
    "peerID": peerID,
    "state": state
]

I'm using MultipeerConnectivity: peerID is of type MCPeerID (e.g., MCPeerID(displayName: "morpheus")), and state is MCSessionState (an enum, e.g., MCSessionState.Connected). Apparently, I cannot convert an enum to AnyObject? How can I solve this?

Best.

Edit: I tried using Dictionary<String, Any>, but now I get an exception in the next call. Here's the code:

func session(session: MCSession!, peer peerID: MCPeerID!, didChangeState state: MCSessionState) {

    var dict: Dictionary<String, Any> = [
        "peerID": peerID,
        "state": state
    ]

    NSNotificationCenter.defaultCenter().postNotificationName(
        "MCDidChangeStateNotification",
        object: nil,
        userInfo: dict
    )
}

Xcode indicates the "userInfo: dict" line with the exception:

Thread 10: EXC_BAD_INSTRUCTION (code=EXC_I386_INVOP, subcode=0x0)

Maybe this won't tell you much, so what could I post that would help?

Edit:

By inspecting the object at runtime (after the crash), this is what I get:

state   MultipeerConnectivity.MCSessionState    Connecting  Connecting
dict    Swift.Dictionary<Swift.String, protocol<>>      
    [0] Swift._DictionaryElement<Swift.String, protocol<>>      
         key    Swift.String    "state" 
             core   Swift._StringCore       
         value  protocol<>      
             payload_data_0 Builtin.RawPointer  0x0 
             payload_data_1 Builtin.RawPointer  0x0 
             payload_data_2 Builtin.RawPointer  0x0 
             instance_type  Builtin.RawPointer  0x0

There seem to be some null pointers there, but the "state" variable seems fine...

Note: I commented out the peerID assignment.

Upvotes: 1

Views: 3073

Answers (3)

Abhi Beckert
Abhi Beckert

Reputation: 33369

Apparently, I cannot convert an enum to AnyObject? How can I solve this?

That's correct, AnyObject cannot contain enums.

I tried using Dictionary<String, Any>, but now I get an exception in the next call.

NSNotificationCentre doesn't take a swift Dictionary, it takes an NSDictionary.

Wherever possible, Dictionary and NSDictionary are inter-operable however NSDictionary can only have objects as the key and value. You cannot use Any in a dictionary that needs to be treated as if it were an NSDictionary by an obj-c API such as NSNotificationCentre.

So, long story short, a notification userInfo dictionary has to be Dictionary<AnyObject, AnyObject> (or <String, String> or something that is an object). You're going to have to use something other than an Enum.

Upvotes: 2

Jiaaro
Jiaaro

Reputation: 76928

I think you need to use type Any for the dictionary values (because AnyObject can only be used for an instance of a class):

This worked in a playground for me:

var dict: Dictionary<String, Any> = [
    "peerID": peerID,
    "state": state
];

Upvotes: 1

Lukas
Lukas

Reputation: 3133

AnyObject is only for class types, use Any to also support enums (cf. docs).

Upvotes: 3

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