Lua: Calling c method that returns userdata to Lua
Im using LuaObjcBridge and I'm calling a method from Lua like this:
local position = owner:position()
In objective-c this returns a CGPoint struct with X and Y which the bridge converts into Userdata. So CGPoint struct -> Lua userdata. In Lua how would I access the X and Y 开发者_JAVA百科values from the Userdata?
you need to:
- define metatable, that contains methods that operate on userdata
- set metatable on userdata
- set the same metatable as __index field on userdata
or:
- set some methods that operate on userdata
- expose them to Lua
look at http://www.lua.org/pil/28.1.html
userdata can't do anything by itself, you need to add methods that do something with it.
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