There is a crash, I can not figure it !

[usiege]

0 libobjc.A.dylib	objc_msgSend + 16
1 UXReader	-[UXReaderDocumentPage renderTileInContext:] + 1032
2 UXReader	-[UXReaderPageTiledView drawLayer:inContext:] + 64
3 QuartzCore	-[CALayer drawInContext:] + 296
4 QuartzCore	tiled_layer_render(_CAImageProvider*, unsigned int, unsigned int, unsigned int, unsigned int, void*) + 1532
5 QuartzCore	CAImageProviderThread(unsigned int*, bool) + 812
6 libdispatch.dylib	__dispatch_client_callout + 16
7 libdispatch.dylib	__dispatch_queue_override_invoke$VARIANT$mp + 716
8 libdispatch.dylib	__dispatch_root_queue_drain + 600
9 libdispatch.dylib	__dispatch_worker_thread3 + 120
10 libsystem_pthread.dylib	_pthread_wqthread + 1268

[usiege]

Please check it out！

[KronosRemote]

This looks pretty much like the issues I'm having as well. As far as I can tell UXReader is not properly threadsafe, drawing is performed on CALayers on a separate thread (UXReader even introduces its own dispatch queue) but references to the pdf document object and other stuff are handed down the chain and used from everywhere, leading to crashes. In my case I'm having the issues if I change the pdf document quickly, so the previous document is replaced while the drawing functions are still accessing it. Correct me if I'm wrong but this is what I've found so far. Haven't found a fix for it yet...