Objective-c Completion handler to Delphi

[loki5100 7]

In Objective-c header I have this :

- (void)offerForConstraints:(RTCMediaConstraints *)constraints
          completionHandler:(nullable void (^)(RTCSessionDescription *_Nullable sdp,
                                               NSError *_Nullable error))completionHandler;

That I translate like this:

type

  TWebRTCPeerConnectionOfferForConstraintsCompletionHandler = 
    procedure(sdp: RTCSessionDescription; error: NSError) of object;

procedure offerForConstraints(
  constraints: RTCMediaConstraints; 
  completionHandler: TWebRTCPeerConnectionOfferForConstraintsCompletionHandler); cdecl;

But every time I call offerForConstraints I Have :

Access violation at address 0000000183398910, accessing address 0000000EBA24BEB8

Any idea what going wrong?

[Allen@Grijjy 44]

Is that completion handler actually a objective-c block?  If so, you need to implement it as a block.  We discuss how to do this more easily from Delphi in an article we wrote on using Apple's Grand Central Dispatcher that might help,

https://blog.grijjy.com/2018/05/20/using-the-apples-grand-central-dispatch-and-androids-scheduledthreadpoolexecutor-for-delphi-timers/