ios - NSProxy and forwardInvocation: invoke called within a block causes nil return value -

I am using a NSProxy subclass and forwardInvocation: For my backend API object (a shared frequency) to capture calls

Some background information: I want to capture API calls so that I can check every time if I need to refresh my authentication token if so, then I just refresh it before

The method parameters ( invocation of) are blocked.

A few simple codes:

  - (zero) forwarded charge: (nsiivation *) invocation {[invoice setagraph: self ali api]; [Arguments to keep the invitation]; // Refresh Call and after successfully refreshing // successfully refresh after record. (Authenticity Reproduction) {[Self. Real API refresh: withblock: ^ (NSObact * some object) {[Inoculation avalicious target: self-ali API]; }]; } // Otherwise we only want to immediately greet {{invention} next to it. Goal: AutoApi]; } Return; } Calling  retainingArguments  already due to the last execution of   
  invokeWithTarget:    
 Yes, so my blocks and other parameters are not lost ( refresh with block:  calls an async API).  
 Everything works fine till now - but:  
  return value  is always a  zero  when  invokeWithTarget:  is done within the refresh block is there any way to retain the return value (eg logic)?  
 Any hint? suggestion?  
 
  Update   
 @ Reply to Clash of the Answer: The problem is that the return value is type  NSURLSessionDataTask  That I use to show an activity indicator) which I read directly after calling. But the proxy does not immediately send calls, so the return value is not there - of course (I was blind). What would be possible solutions? Can I return the placeholder value or how the method is brought when I can call it as collar, can I get the return value later?   
 
 
 When your call is completed, to pass the result:  
  if (authentication is refreshed) {{self.realAPI fresh with block: ^ (NSObject * someObject) {NSURLSessionDataTask * resultTask = zero; [Greeting call statement: Target. [Invitation getReturnValue: and resultsTest]; If (complete! = Zero) {complete (resultTask); }}]; }   
 Where  is complete ()  is a block that takes the  NSURLSessionDataTask  as the parameter used as a callback That is, whatever you are trying to do is well suited ("when I am doing this, I do it") Ideally, it would pass in the above method - but it can be passed on to the  Forwarding frequency is: , which is a bit more ... challenging. You can set it as a property on this proxy object and you can read it from there.  addDataTask:  which you can call instead of your block, which can "turn off the responsibilities for", another way is to expand the UIIP with a class or informal protocol. I've just added a Data Reichizer, most likely that the representative of the application (and you can increase the UIiproduction Delegate protocol to handle a new method,  application: didAddDataTask: ) It looks like your data task and activity indicators are application-level concerns, which can make it a good fit.  
 He said, I have been trying to solve some experiences with almost  absolutely  problems (token based authorization) I suggest that the approach of this problem How it's reached, it can offer some ideas for alternative implementations.