CODEWITHSUNDEEP
c#lua
Dusty
Dusty

Reputation: 423

Lua.GetFunction Returns Null

I'm very new to lua this is my first program to use it at all. The code uses a Lua File to create a menu for a game I'm working on.

This line creates a button in the MainMenu screen, it sends the name of the function to call when the button is pressed.

Lua:

CreateButton( "mainmenu", "NewGame", "New Game", 50, 120, 150, 32)

function NewGame()
--CODE TO START NEW GAME
end

C#:

public class LuaWrapper
{
    public void Initialize()
    {
        lua = new Lua();
        lua.RegisterFunction("CreateButton", this, 
           this.GetType().GetMethod("CreateButton"));

        lua.DoFile("Data/Menus/Main.lua");
    }

    public void CreateButton(string window, string functionName, string text,
         float posx, float posy, float width, float height)
    {
        ButtonControl button = new ButtonControl();
        button.Bounds = new UniRectangle(posx, posy, width, height);
        button.Text = text;
        LuaFunction f = lua.GetFunction(functionName); // <-- RETURNS NULL ?

        ButtonPressEvent pressEvent = new ButtonPressEvent(f);
        button.Pressed += new EventHandler(pressEvent.button_Pressed);

        WindowDictionary[window].Children.Add(button);
    }
}

class ButtonPressEvent
{
    LuaFunction function;

    public ButtonPress(LuaFunction function)
    {
        this.function = function;
    }

    public void button_Pressed(object sender, EventArgs e)
    {
        function.Call();
    }
}

It all works fine until the button is clicked and it tries to call the associated function It throws a Null Reference Exception on Funtion.Call(); Under the ButtonPress Class. I have used break points and found out that the problem is

 LuaFunction f = lua.GetFunction(functionName);

returns Null.

Note: I've also tried 

LuaFunction f = lua.GetFunction("NewGame");

With the same results.

Thanks Reading, hope any one can help point out what I've done wrong.

Upvotes: 0

Views: 860

Answers (1)

Dusty
Dusty

Reputation: 423

I had a thought and tried changing the order of the Lua File. I guess I was calling the creation of the button before The function had been read ? I'm not sure but this seems to have fixed it.

Lua:

function NewGame()
--CODE TO START NEW GAME
end

CreateButton( "mainmenu", "NewGame", "New Game", 50, 120, 150, 32)

Upvotes: 1

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