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objective c - When to override updateTrackingAreas -


so have quite big nsscrollview several custom views in it. in these custom views i'm overriding -(void)updatetrackingareas this:

- (void)updatetrackingareas { [self removetrackingarea:trackingarea]; trackingarea = [[nstrackingarea alloc] initwithrect:[self bounds] options:(nstrackingcursorupdate | nstrackingactivewhenfirstresponder | nstrackinginvisiblerect) owner:self userinfo:nil]; [self addtrackingarea:trackingarea]; }

but somehow feel little unefficient since have 50 instances of custom view in nsscrollview , 5 of them visible @ time , way i'm updating tracking areas of non-visible views.

so thought skip updating tracking areas if view not in nsscrollview's visible rect. like:

- (void)updatetrackingareas { if(!nsintersectsrect([self frame], [[self superview] visiblerect])) { return; } // ... }

this seems working out i'm not sure if safe.

does have advice on matter?

objective c - when override updatetrackingareas - stack overflow

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so have quite big nsscrollview several custom views in it. in these custom views i'm overriding -(void)updatetrackingareas this:

- (void)updatetrackingareas { [self removetrackingarea:trackingarea]; trackingarea = [[nstrackingarea alloc] initwithrect:[self bounds] options:(nstrackingcursorupdate | nstrackingactivewhenfirstresponder | nstrackinginvisiblerect) owner:self userinfo:nil]; [self addtrackingarea:trackingarea]; }

but somehow feel little unefficient since have 50 instances of custom view in nsscrollview , 5 of them visible @ time , way i'm updating tracking areas of non-visible views.

so thought skip updating tracking areas if view not in nsscrollview's visible rect. like:

- (void)updatetrackingareas { if(!nsintersectsrect([self frame], [[self superview] visiblerect])) { return; } // ... }

this seems working out i'm not sure if safe.

does have advice on matter?

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