Hi, all!
I used the enterprise only several weeks.
So please understand if it is silly question.
I have to send a bit of large array from Lua to Native and vice versa.
I’ve look over LuaPluginLibrary.mm could send integer and string argument to Lua from Objective-C.
How to send an table variable from Lua to Native, that is, Objective-C and Java?
Have a look at Corona Enterprise’s sample project “SimpleLuaExtension”. Particularly the “GetRandomArrayLuaFunction.java” and the “PrintArrayLuaFunction.java” files. Those 2 source files contain the answers that you are looking for, with plenty of comments explaining how it works. :)
In fact, that sample project has a lot of great examples on how to work with the LuaState in Java and C in general. It’ll help you learn the fundamentals of working with Lua from native code.
You can also find documentation for the Java version of the LuaState here…
http://docs.coronalabs.com/daily/native/android/html/com/naef/jnlua/package-summary.html
I hope this helps!
Thanks for reply, Jushua.
I need that for iOS, however, all of method are not implemented for iOS.
So I’ve checked that Android source code of “SimpleLuaExtention”.
I found luaL_checktype(lua_State *L, int narg, int t) but I cannot found how to fit into 2nd and 3rd argument.
Original checkType code for Android like followings:
// Check if the Lua function's first argument is a Lua table. // Will throw an exception if it is not a table or if no argument was given. int luaTableStackIndex = 1; luaState.checkType(luaTableStackIndex, com.naef.jnlua.LuaType.TABLE); // Print all of the key/value paris in the Lua table. System.out.println("printTable()");You can find the official Lua API documentation, as written by Lua’s creator, here…
There’s also a 3rd party API documentation site for Lua which sometimes provides better detail about the Lua’s C functions which I find helpful.
Notice that the Java LuaState methods are near 1-to-1 with the C function equivalents. The difference being is in C you have to pass the lua_State pointer as the first argument since C is not an object oriented language.
So, in regards to the luaL_checktype() function, you need to provide the following arguments as described by the documentation I provided links to up above…
Argument 1: The lua_State pointer.
Argument 2: Index to the Lua object on the stack that you want to check the type of.
Argument 3: The Lua type to check for such as LUA_TNUMBER, LUA_TSTRING, etc.
Thank you very much, Joshua!
Have a look at Corona Enterprise’s sample project “SimpleLuaExtension”. Particularly the “GetRandomArrayLuaFunction.java” and the “PrintArrayLuaFunction.java” files. Those 2 source files contain the answers that you are looking for, with plenty of comments explaining how it works. :)
In fact, that sample project has a lot of great examples on how to work with the LuaState in Java and C in general. It’ll help you learn the fundamentals of working with Lua from native code.
You can also find documentation for the Java version of the LuaState here…
http://docs.coronalabs.com/daily/native/android/html/com/naef/jnlua/package-summary.html
I hope this helps!
Thanks for reply, Jushua.
I need that for iOS, however, all of method are not implemented for iOS.
So I’ve checked that Android source code of “SimpleLuaExtention”.
I found luaL_checktype(lua_State *L, int narg, int t) but I cannot found how to fit into 2nd and 3rd argument.
Original checkType code for Android like followings:
// Check if the Lua function's first argument is a Lua table. // Will throw an exception if it is not a table or if no argument was given. int luaTableStackIndex = 1; luaState.checkType(luaTableStackIndex, com.naef.jnlua.LuaType.TABLE); // Print all of the key/value paris in the Lua table. System.out.println("printTable()");You can find the official Lua API documentation, as written by Lua’s creator, here…
There’s also a 3rd party API documentation site for Lua which sometimes provides better detail about the Lua’s C functions which I find helpful.
Notice that the Java LuaState methods are near 1-to-1 with the C function equivalents. The difference being is in C you have to pass the lua_State pointer as the first argument since C is not an object oriented language.
So, in regards to the luaL_checktype() function, you need to provide the following arguments as described by the documentation I provided links to up above…
Argument 1: The lua_State pointer.
Argument 2: Index to the Lua object on the stack that you want to check the type of.
Argument 3: The Lua type to check for such as LUA_TNUMBER, LUA_TSTRING, etc.
Thank you very much, Joshua!
For what it’s worth, I just rewrote the PrintTableLuaFunction.java for iOS. Probably not the best rewrite but hopefully it helps someone!
[lua]
//check type. if it’s not a table it will throw an error/exception.
luaL_checktype(L, 1, LUA_TTABLE);
//print all of the key/value pairs in the Lua table
NSLog(@“printTable()”);
NSLog(@"{");
for (lua_pushnil(L); lua_next(L, 1); lua_pop(L, 1)) {
const char *keyName = NULL;
int luaType = lua_type(L, -2);
switch (luaType) {
case LUA_TSTRING:
// Fetch the table entry’s string key.
keyName = lua_tostring(L, -2);
break;
case LUA_TNUMBER:
// The key will be a number if the given Lua table is really an array.
// In this case, the key is an array index. Do not call lua_tostring() on the
// numeric key or else Lua will convert the key to a string from within the Lua table.
keyName = [[NSString stringWithFormat:@"%d", lua_tointeger(L, -2)] cStringUsingEncoding:NSASCIIStringEncoding];
break;
}
if (keyName == NULL) {
//a valid key was not found. skip this table entry.
continue;
}
//fetch the table entry’s value in string form.
//an index of -1 accesses the entry’s value that was pushed into the lua stack by lua_next() above.
const char *valueString = NULL;
luaType = lua_type(L, -1);
switch (luaType) {
case LUA_TSTRING:
valueString = lua_tostring(L, -1);
break;
case LUA_TBOOLEAN:
valueString = [[NSString stringWithFormat:@"%d", lua_toboolean(L, -1)] cStringUsingEncoding:NSASCIIStringEncoding];
break;
case LUA_TNUMBER:
valueString = [[NSString stringWithFormat:@"%f", lua_tonumber(L, -1)] cStringUsingEncoding:NSASCIIStringEncoding];
break;
}
if (valueString == NULL) {
valueString = “”;
}
NSLog(@"[%s] = %s", keyName, valueString);
}
NSLog(@"}");
[/lua]
For what it’s worth, I just rewrote the PrintTableLuaFunction.java for iOS. Probably not the best rewrite but hopefully it helps someone!
[lua]
//check type. if it’s not a table it will throw an error/exception.
luaL_checktype(L, 1, LUA_TTABLE);
//print all of the key/value pairs in the Lua table
NSLog(@“printTable()”);
NSLog(@"{");
for (lua_pushnil(L); lua_next(L, 1); lua_pop(L, 1)) {
const char *keyName = NULL;
int luaType = lua_type(L, -2);
switch (luaType) {
case LUA_TSTRING:
// Fetch the table entry’s string key.
keyName = lua_tostring(L, -2);
break;
case LUA_TNUMBER:
// The key will be a number if the given Lua table is really an array.
// In this case, the key is an array index. Do not call lua_tostring() on the
// numeric key or else Lua will convert the key to a string from within the Lua table.
keyName = [[NSString stringWithFormat:@"%d", lua_tointeger(L, -2)] cStringUsingEncoding:NSASCIIStringEncoding];
break;
}
if (keyName == NULL) {
//a valid key was not found. skip this table entry.
continue;
}
//fetch the table entry’s value in string form.
//an index of -1 accesses the entry’s value that was pushed into the lua stack by lua_next() above.
const char *valueString = NULL;
luaType = lua_type(L, -1);
switch (luaType) {
case LUA_TSTRING:
valueString = lua_tostring(L, -1);
break;
case LUA_TBOOLEAN:
valueString = [[NSString stringWithFormat:@"%d", lua_toboolean(L, -1)] cStringUsingEncoding:NSASCIIStringEncoding];
break;
case LUA_TNUMBER:
valueString = [[NSString stringWithFormat:@"%f", lua_tonumber(L, -1)] cStringUsingEncoding:NSASCIIStringEncoding];
break;
}
if (valueString == NULL) {
valueString = “”;
}
NSLog(@"[%s] = %s", keyName, valueString);
}
NSLog(@"}");
[/lua]