How do I switch keyboard layout programmatically in MacOS X?

how do I switch keyboard layout (AKA input source) programmatically in MacOS X in a Cocoa/Objective C prog开发者_如何学Pythonram? Thanks in advance.

I've not had occasion to try this, but I think you want the functions in text input source services. Note that these are Carbon functions, though usable from Cocoa -- you'll need to add the Carbon framework to your project in order to use them.