Question

How do you encode and decode a CGPoint struct using NSCoder?

Answer 1

CGPoints and NSPoints are both structures composed of two CGFloat values, so you can freely pass them around as each other. The quick and dirty way would be:

NSCoder *myNSCoder; CGPoint myPoint; [myNSCoder encodePoint:*(NSPoint *)myPoint]; 

This will usually work, but it technically breaks the C99 strict aliasing rules. If you want to be 100% compatible with the standard, you’ll have to do something like:

typedef union {   CGPoint cgPoint;   NSPoint nsPoint; } CGNSPoint;  CGNSPoint cgnsPoint = { .cgPoint = myPoint }; [myNSCoder encodePoint:cgnsPoint.nsPoint];