The emission and the treatment of a custom event. Very simple to understand.
The most important thing to know is : An event must be captured by at least one object, it's why every Gtk element that as an event like "Clicked" as a protected method "OnClicked".
// Event.cs
// Playing with lists !
// Copyright 2005, Yoan BLANC <yoan @ dosimple.ch>, HE-ARC (he-arc.ch)
//
// distibuted under the GPLv2 : http://opensource.org/licenses/gpl-license.php
using Gtk;
using System;
// main app
public class Event
{
public static void Main(string[] args)
{
Application.Init();
new EventTest("Event test");
Application.Run();
}
}
// the window
public class EventTest : Window
{
public event LabelEventHandler ButtonClicked;
public EventTest(string title) : base(title)
{
DeleteEvent += Window_Delete;
ButtonClicked += OnButtonClicked;
VBox v = new VBox();
v.BorderWidth = 6;
// --
Button a = new Button("a");
Button b = new Button("b");
Button c = new Button("c");
a.Clicked += onClick;
b.Clicked += onClick;
c.Clicked += onClick;
v.Add(a);
v.Add(b);
v.Add(c);
// --
ButtonClicked += myOnButtonClicked;
// --
Add(v);
ShowAll();
}
// recieve the click, emit the label
private void onClick(object sender, EventArgs args)
{
LabelEventArgs largs = new LabelEventArgs(((Button)sender).Label);
ButtonClicked(this, largs);
}
protected void OnButtonClicked(object sender, EventArgs args)
{
// pass
}
// recieve the label
private void myOnButtonClicked(object sender, LabelEventArgs args)
{
Console.WriteLine(args.Label + " clicked !");
}
// close the window
private static void Window_Delete (System.Object o, DeleteEventArgs args)
{
Application.Quit ();
args.RetVal = true;
}
}
// the handler
public delegate void LabelEventHandler (object sender, LabelEventArgs e);
// my event args
public class LabelEventArgs : EventArgs
{
public string Label
{
get
{
return _label;
}
}
public LabelEventArgs (string label) : base()
{
_label = label;
}
private string _label;
}
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