Lua learning 2) -- interaction between Android and Lua, androidlua

Lua learning 2) -- interaction between Android and Lua, androidlua

2014-07-09

1. Android class calls lua and calls back

Android calls the Lua function, transmits the class as a parameter, and then calls back the class function in Lua.

Call lua

MLuaState = LuaStateFactory. newLuaState (); mLuaState. openLibs (); mLuaState. ldoString (KKLua. loadAssetsString (mContext, "lua/swallow. lua "); // converts lua to the string mLuaState. getField (LuaState. LUA_GLOBALSINDEX, "luaUpdate"); // obtain functionmLuaState in lua. pushJavaObject (this); // pass the mLuaState parameter. call (1, 0); // a parameter with 0 returned values

Callback Interface

Public void luaDraw (int imageId, int x, int y, int scale) {// note that it must be public before lua can be called to System. out. println ("imageId, x, y, scale:" + imageId + "," + x + "," + y + "," + scale );}

Lua code

function luaUpdate(luaCanvas)  luaCanvas:luaDraw(0, 1, 2, 1)end

II. Introduction to luajava ( Included in the LuaJava Library)

There is no class in lua. The luajava library has a luajava class that can be created and called in java. The following describes several methods:

① NewInstance (className ,...)

Note: You can create a Java class based on the class name and return a lua variable corresponding to the Java class. In this way, you can directly call methods in Java in lua.

obj = luajava.newInstance("java.lang.Object")-- obj is now a reference to the new object-- created and any of its methods can be accessed.-- this creates a string tokenizer to the "a,b,c,d"-- string using "," as the token separator.strTk = luajava.newInstance("java.util.StringTokenizer",     "a,b,c,d", ",")while strTk:hasMoreTokens() do    print(strTk:nextToken())end

② BindClass (className)

Note: You can set variables in lua to correspond to a Java class (a class, not an instance). In this way, you can use the variables in lua to create instances and call static classes.

sys = luajava.bindClass("java.lang.System")print ( sys:currentTimeMillis() )-- this prints the time returned by the function.

③ New (javaClass)

Note: This is created on the basis of ②.

str = luajava.bindClass("java.lang.String")strInstance = luajava.new(str)

④ CreateProxy (interfaceNames, luaObject)

⑤ LoadLib (className, methodName)

These two methods are not used yet, and will be used later

Thank you!

Teach you a question about porting android to the lua project in cocos2d-x

Build_native.sh




I have been studying androidfor more than two months. Now I want to learn the android source code, but which of the following classes should I look at first?

First look at activityManager, which is the process for managing the entire activity from startup to destruction!