Re: [Libqtlua-list] Accessing QObject inside a property in Lua

[Alexandre Becoulet]

On Tuesday, January 11, 2011 03:27:53 pm Gustavo de Sá Carvalho Honorato 
wrote:

Hi,

> I'm trying to access my MainWindow class throught a property which is
> declared inside my Application class in Lua. I've declared the
> MainWindow using Q_DECLARE_METATYPE(MainWindow*) and
> qRegisterMetaType<MainWindow*>(). I've exposed my application class
> using state["app"] = QtLua::Value(state, qApp, false).
> 
> The problem occurs when I try to access the MainWindow by typing
> app.mainWindow:close() in Lua Console, and I got the error "error:
> [string ""]:1: attempt to index field 'mainWindow' (a nil value)".
> 
> It's quite weird because when I type list(app) I can see that the
> property mainWindow has a value QtLua::Property<MainWindow*>
> mainWindow = Application::mainWindow.

QtLua has no way to guess how to convert your declared meta type to a 
QtLua::Value. Try using a QObject* or QWidget* instead of a MainWindow* 
pointer type.

Lua/Qt values convertion on property access and method call is performed by 
raw_get_object and raw_set_object in src/qtluamember.cc. Supporting dynamic 
declaration of new types would require registering two callbacks to implement 
value convertion, I can implement this if there is a real need.

-- 
Alexandre