学步园

Lua的目标是成为一个很容易嵌入其它语言中使用的语言。很多应用程序使用LUA作为自己的嵌入式脚本语言，以此来实现可配置性、可扩展性，以便程序更灵活和更好的扩展。

//  ViewController.m
//  wwwwww
//
//  Created by Tolecen 12-11-19.
//  Copyright (c) 2012年 Tolecen . All rights reserved.

//

#import "ViewController.h"
#include "lua.hpp"
extern "C"
{
#include "lua.h"
#include "lualib.h"
#include "lauxlib.h"
}
#define NOERROR 0
#define LUA_PMCNT_CHECK(n)\
{ \
int nParamCnt = lua_gettop(L) ; \
if( nParamCnt != n ) \
    {\
        lua_pushnumber( L , -1 ) ; \
        return 1 ; \
    } \
}

#define LUA_RET_VALUE(n)\
{ \
    lua_pushnumber( L , n );  \
return 1 ; \
}

#define LUA_OUT_ERROR(id) lua_pushnumber(L, id);if (id != 0) return 1;

int logYouWhat(lua_State *L)  //你想要让Lua执行的方法，需用C++写
{
    LUA_PMCNT_CHECK(2);
    int aa = (int)lua_tonumber(L, 1);
    int bb = (int)lua_tonumber(L, 2);
    NSLog(@"aa:%d,bb:%d",aa,bb);
    [ViewController changeA:aa B:bb]; //在此c++方法里通过这个ViewController的类方法调用OC方法，以实现设置UI等操作
    return 0;
}


unsigned long luaWork(void* pParam) //此方法用来调用Engine.lua，以驱动Lua语句
{
    int i;
    int j;
    int s0;
    int s1;
    int nResult;
    lua_State *L;
    int nThreadIndex;
    lua_State *lLocal;
    char strPathName[512];
    char strLuaEngine[512];
    NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
    NSString *documentsDirectory = [paths objectAtIndex:0];
    memset(strPathName, 0, 512);
    const char * tmp=  [documentsDirectory UTF8String];
    strncpy(strPathName, (char*)tmp, strlen(tmp)); //这是查找本地App的Documents语句，以便将lua文件加到此处   
    L = luaL_newstate();
    if (L == NULL)
    {
         NSLog(@"error: %s \n" , lua_tostring(L, -1)); //lua程序执行有错误，此处会打印lua的错误行数，下同
         return -1;
    }
    luaL_openlibs(L);
    j = 0;
    for (i = 0;i < 260;i++)
    {
        if (strPathName[i] == 0)
            break;       
        if (strPathName[i] == '\\')
        j = i;
     }    
    if (j != 0)
    strPathName[j] = 0;
    NSString *logPath = [documentsDirectory stringByAppendingPathComponent:@"Engine.lua"];
    const char * tmp1=  [logPath UTF8String];
    strncpy(strLuaEngine, (char*)tmp1, strlen(tmp1));
    NSLog(@"strLuaEngine %s \n",strLuaEngine);
    s1 = luaL_loadfile(L, strLuaEngine); //通过Engine.lua的路径load lua文件，实现要将Engine.lua和todo.lua存入目录
    if (s1 != 0)
    {          
        NSLog(@"error: %s \n" , lua_tostring(L, -1));
        lua_pop(L, 1);
        return -10;
    }   
    s1 = lua_pcall(L, 0, 0, 0);
    if (s1 != 0)
    {
        NSLog(@"error: %s \n" , lua_tostring(L, -1));
        getchar();
        lua_pop(L, 1);
        return -11;
    }
    lua_register(L, "logSomething", logYouWhat);//将这个Viewcontroller中的方法在Lua中注册，中间那个就是要在lua里执行的方     法名
    lua_getglobal(L, "ywyengine");    
    if (!lua_istable(L, -1))
    {
        NSLog(@"error: %s \n" , lua_tostring(L, -1));
        lua_pop(L, 1);
        return -3;
    }   
    lua_pushstring(L, "CreateSession");
    lua_gettable(L, -2);   
    if (!lua_isfunction(L, -1))
    {
        NSLog(@"error: %s \n" , lua_tostring(L, -1));
        lua_pop(L, 2);
        return -4;
    }    
    s0  = lua_pcall(L, 0, 2, 0);
    if (s0 != 0)
    {
        NSLog(@"error: %s \n" , lua_tostring(L, -1));
        lua_pop( L, 1 );
        return -5;
    }   
    lLocal = lua_tothread(L, -2);
    nThreadIndex = lua_tonumber(L, -1);    
    lua_pop(L, 2);    
    while(1)
    {
        NSLog(@"run");
        lua_getglobal(L, "ywyengine");        
        if (!lua_istable(L, -1))
        {
             NSLog(@"error: %s \n" , lua_tostring(L, -1));
            lua_pop(L, 1);
            return -6;
        }       
        lua_pushstring(L, "ContinueSession");
        lua_gettable(L, -2);
        if (!lua_isfunction(L, -1))
        {
            NSLog(@"error: %s \n" , lua_tostring(L, -1));
            lua_pop(L, 2);
            return -7;
        }       
        lua_pushnumber(L, nThreadIndex);       
        s0  = lua_pcall(L, 1, 1, 0);
        if (s0 != 0)
        {
            NSLog(@"error: %s \n" , lua_tostring(L, -1));
            lua_pop( L, 1 );
            return -8;
        }       
        nResult = lua_tonumber(L, -1);
        lua_pop(L, 1);       
        if (nResult)
        return -9;
    }    
    return 0;
}
@interface ViewController ()
@end

@implementation ViewController
- (void)viewDidLoad
{
    [super viewDidLoad];   
    dispatch_queue_t queue = dispatch_queue_create("com.example.dothis", NULL);
    dispatch_async(queue, ^{
        luaWork(NULL);
    });
// Do any additional setup after loading the view, typically from a nib.
}

+(void)changeA  int)as B  int)bs
{
    NSLog(@"hahaTHEA:%d",as);
}

Engine.lua的代码

require("/var/mobile/Applications/4FDA7C3C-984F-43C9-A306-6C95C758AF78/Documents/todo")
--上面是将todo.lua的路径交代给Engine.lua，以便调用todo.lua里的方法，每一个程序的路径不一样，要改成自己程序的路径
threadhandle = {}
handlecount = 0
ywyengine = {}

function ywyengine.Susport(  )
coroutine.yield()
end

function ywyengine.ContinueSession( handleindex )
local status, err, result

if (type(threadhandle[handleindex]) ~= "thread") then
print( "ContinueSession error no thread" ) 
result = 1
return result
end
if (threadhandle[handleindex] == nil) then
print( "ContinueSession error thread nil" ) 
result = 2
return result
end

if (coroutine.status( threadhandle[handleindex] ) == "dead") then
result = 3
print( "ContinueSession error thread dead" ) 
threadhandle[handleindex] = nil
return result
end
status , err = coroutine.resume( threadhandle[handleindex] , 0 )

  if status == false then
  result = 4
  print( "ContinueSession error" ) 
  print(err)
  else
    result = 0
end 
print( "ContinueSession ok" ) 
return result
end

function ywyengine.CreateSession()
    local handle = coroutine.create( StartSession )
    local status, err
    local sessioninfo = {}
    local coroutine_info = {
        param   = sessioninfo ,  
      }
   
    handlecount = handlecount + 1
    threadhandle[handlecount] = handle    
    status, err = coroutine.resume( threadhandle[handlecount] , coroutine_info )  
    if status == false then
         print( "CreateSession error" ) 
    print(err)
    end
 
    print("Start session ok")
  return handle, handlecount
end

function StartSession(args)

while true do
       logSomething(45,78);//这就是viewcontroll中注册的那个方法，对应的c++方法在上方已写
       print("Continue ok");
       ywyengine.Susport();
end
end

lua在Xcode的配置参照博客 http://www.cnblogs.com/hurricane2011/articles/2252368.html