Proxying in PXSourceList 2

The slides from my Cocoa Kucha 2 talk at NSLondon in January 2014. I talked about the new proxy-based implementation in PXSourceList version 2.

Video here: http://vimeo.com/86478379

Transcript

1. Alex Rozanski @alexrozanski github.com/Perspx PROXYING in PXSourceList 2
2. PXSourceList in Action
3. -outlineView:numberOfChildrenOfItem: -outlineView:viewForTableColumn:item: -outlineView:objectValueForTableColumn:byItem: -outlineView:shouldExpandItem: -outlineView:heightOfRowByItem: ... ...
4. -sourceList:numberOfChildrenOfItem: -sourceList:viewForItem: -sourceList:objectValueForItem: -sourceList:shouldExpandItem: -sourceList:heightOfRowByItem: ... ... -sourceList:badgeValueForItem: -sourceList:iconForItem:
5. - (BOOL)outlineView:(NSOutlineView *)outlineView shouldExpandItem:(id)item { SEL newSelector = @selector(sourceList:shouldExpandItem:); if ([_actualDelegate respondsToSelector:newSelector]) return [_actualDelegate sourceList:self shouldExpandItem:item]; return YES; }
6. -respondsToSelector:
7. NSOutlineView Proxy Delegate Data Source
8. NSProxy
9. -methodSignatureForSelector: -forwardInvocation: -doesNotRecognizeSelector: nil non-nil
10. -methodSignatureForSelector: -forwardInvocation: -doesNotRecognizeSelector: nil non-nil Forward message!
11. -respondsToSelector: -forwardInvocation: -methodSignatureForSelector: NSProxy
12. -respondsToSelector: Source List? Real delegate/data source? Return YES Return YES Return NO Translate selector
13. -methodSignatureForSelector: protocol_getMethodDescription()
14. -methodSignatureForSelector: protocol_getMethodDescription( Protocol *, SEL, BOOL isRequiredMethod, BOOL isInstanceMethod )
15. -methodSignatureForSelector: struct objc_method_description description = {NULL, NULL}; ! for (NSUInteger i = 0; i < 4; ++i) { description = protocol_getMethodDescription(protocol, selector, (i / 2) % 2, i % 2 ); if (description.types != NULL && description.name != NULL) break; }
16. -methodSignatureForSelector: +[NSMethodSignature signatureWithObjCTypes:] struct objc_method_description { SEL name; char *types; }
17. -forwardInvocation: Source List responds? Invoke on real delegate/data source Invoke on! Source List Translate selector Modify arguments
18. PXSourceList Delegate and Data Source Proxy NSOutlineView delegate/data source methods
19. PXSourceList Delegate and Data Source Proxy NSOutlineView delegate/data source methods
20. [self.delegateDataSourceProxy outlineView:self numberOfChildrenOfItem:nil]; PXSourceList.m: [ actualDataSource sourceList:self numberOfChildrenOfItem:nil];
21. github.com/Perspx/PXSourceList/tree/2.0 @alexrozanski