ios - Multiple delegates for one object? (follow-up) -


on question multiple delegates per 1 object? 1 of answers came interesting solution (at least naive eyes) : creating "delegate splitter" allows object (in case uiscrollview) have multiple delegates (in case uiscrollviewdelegate).

the code follows:

@interface delegatesplitter : nsobject  -(void)adddelegate:(id)delegate; -(void)adddelegates:(nsarray*)array;  @end   @interface delegatesplitter()  @property nsmutableset *delegates;  @end  @implementation delegatesplitter  -(id)init {    self = [super init];    _delegates = [nsmutableset set];    return self; }  -(void)adddelegate:(id)delegate {   [_delegates addobject:delegate]; }  -(void)adddelegates:(nsarray *)array {    [_delegates addobjectsfromarray:array]; }  -(void)forwardinvocation:(nsinvocation *)aninvocation {   (id delegate in _delegates)   {      if([delegate respondstoselector:aninvocation.selector])      {         [aninvocation invokewithtarget:delegate];      }    } }  - (nsmethodsignature*) methodsignatureforselector: (sel) selector {   nsmethodsignature *our = [super methodsignatureforselector:selector];   nsmethodsignature *delegated = [[_delegates anyobject]                                   methodsignatureforselector:selector];   return our ? our : delegated; }  - (bool) respondstoselector: (sel) selector {    return [[_delegates anyobject] respondstoselector:selector]; }

the problem code creates retain cycles, , unlike normal delegate, can't declare 

@property (assign) delegatesplitter *splitter;

it seem "better" solution wrapper. there anyway avoid retain cycle ?

how many delegates going ever need, make property 3 of them , if have need more need radically redesign app...

a better approach have delegate each activity, view delegate, data source, , asynchronous network delegate, etc... if end being same object, cares... work.


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