[Kde-bindings] Qyoto DBUS

[Richard Dale]

On Wednesday 10 January 2007 14:15, Arno Rehn wrote:
> Hi,
>
> I have added most of the marshallers by now, I think, and the ones we need
> for getting dbus to work are also complete.
Great! I've been meaning to do some work on Qyoto for a while, but haven't got 
round to it. It would be really nice to get QDBus working. I've been meaning 
to review your marshaller code - it had lists of 'void*'s which didn't look 
quite right. I think there should be callbacks for each element of a list, 
rather than for a complete list.

> I've again tried to get the 
> listnames example to work, but as before it fails when we try to call get
> the session bus via SessionBus() - it doesn't return a real object.
>
> I tried it with the code from Richard:
> using Qyoto;
> using System;
>
> class ListNames {
>
> 	public static void method2()
>         {
> 		QDBusConnection bus = QDBusConnection.SessionBus();
> 		QDBusInterface dbus_iface = new
> QDBusInterface("org.freedesktop.DBus", "/org/freedesktop/DBus",
> 								"org.freedesktop.DBus", bus);
> 		QDBusMessage result = dbus_iface.Call("ListNames");
> 		QDBusMessage.MessageType mess = result.type();
> 	}
>
> 	public static int Main(string[] args) {
>         	new QCoreApplication(args);
>
> 		if (!QDBusConnection.SessionBus().IsConnected()) {
> 			Console.WriteLine("Cannot connect to the D-BUS session bus.\n" +
> 				"To start it, run:\n" +
> 				"\teval `dbus-launch --auto-syntax`\n");
> 			return 1;
> 		}
>
> 		method2();
> 		Qyoto.Qyoto.DeleteQApp();
> 		return 0;
> 	}
> }
>
> The line
> if (!QDBusConnection.SessionBus().IsConnected()) {
> gives the error
> Unhandled Exception: System.NullReferenceException: Object reference not
> set to an instance of an object
>   at ListNames.Main (System.String[] args) [0x00000]
>
> I don't really know what goes wrong here, other static methods do work
> well. Any ideas?
Hmm, I've just tried it with some debugging messages and it works fine for me:

	public static void method2()
	{
Console.WriteLine("In method2");
		QDBusConnection bus = QDBusConnection.SessionBus();
Console.WriteLine("In method2 bus: {0}", bus);
		QDBusInterface dbus_iface = new 
QDBusInterface("org.freedesktop.DBus", "/org/freedesktop/DBus",
								"org.freedesktop.DBus", bus);
Console.WriteLine("In method2 dbus_iface: {0}", dbus_iface);
		QDBusMessage result = dbus_iface.Call("ListNames");
Console.WriteLine("In method2 result: {0}", result);
		QDBusMessage.MessageType mess = result.type();
Console.WriteLine("In method2 mess: {0}", mess);
	}

mardigras rdale 553% mono listnames.exe
In method2
In method2 bus: Qyoto.QDBusConnection
In method2 dbus_iface: Qyoto.QDBusInterface
In method2 result: Qyoto.QDBusMessage
In method2 mess: ReplyMessage

Are you sure you have dbus running - does the c++ example work ok?

-- Richard