objective c - Why is my hitTest in UIView not identifying CALayer touched -

i have uiview in 2 calayers added [self.layer addsublayer:sublayera]; //... giving following view hierarchy:

uiview subclass  - backing layer (provided uiview)     - sublayera     - sublayerb 

if override touchesbegan in view controller presents uiview correctly identifies calayer touched:

// in view controller  #import <quartzcore/quartzcore.h> //.....  - (void)touchesbegan:(nsset *)touches withevent:(uievent *)event {         uitouch *touch = [touches anyobject];         cgpoint touchpoint = [touch locationinview:self.view];         calayer *touchedlayer = [self.view.layer.presentationlayer hittest:touchpoint];  // returns copy of touchedlayer         calayer *actuallayer = [touchedlayer modellayer];  // returns actual calayer touched         nslog (@"touchpoint: %@", nsstringfromcgpoint(touchpoint));         nslog (@"touchedlayer: %@", touchedlayer);         nslog (@"actuallayer: %@", actuallayer); } 

however, if override touchesbegan in uiview backing layer parent of 2 sublayers, return null calayer (though gives correct touchpoint):

// in uiview subclass  #import <quartzcore/quartzcore.h> //.....  - (void)touchesbegan:(nsset *)touches withevent:(uievent *)event {     uitouch *touch = [touches anyobject];     cgpoint touchpoint = [touch locationinview:self];     calayer *touchedlayer = [self.layer.presentationlayer hittest:touchpoint];  // returns copy of touchedlayer     calayer *actuallayer = [touchedlayer modellayer];  // returns actual calayer touched     nslog (@"touchpoint: %@", nsstringfromcgpoint(touchpoint));     nslog (@"touchedlayer: %@", touchedlayer);     nslog (@"actuallayer: %@", actuallayer); } 

any ideas going wrong?

i had same problem..

calayer's hittest method requires location in coordinates of receiver's super layer.

so adding following line should fix it: touchpoint = [self.layer convertpoint: touchpoint tolayer: self.layer.superlayer]

this explain why test [sublayera hittest:touchpoint] works (touchpoint in coordinate space "self", parent of sublayera)

hope helps.

see: https://developer.apple.com/library/ios/documentation/graphicsimaging/reference/calayer_class/introduction/introduction.html#//apple_ref/occ/instm/calayer/hittest: