GtkSharp/Source/sample/CustomCellRenderer.cs

// CustomCellRenderer.cs : C# implementation of an example custom cellrenderer
// from http://scentric.net/tutorial/sec-custom-cell-renderers.html
//
// Author: Todd Berman <tberman@sevenl.net>
//
// (c) 2004 Todd Berman

using System;

using Gtk;
using Gdk;
using GLib;

public class CustomCellRenderer : CellRenderer
{

	private float percent;

	[GLib.Property ("percent")]
	public float Percentage
	{
		get {
			return percent;
		}
		set {
			percent = value;
		}
	}

	protected override void OnGetSize (Widget widget, ref Rectangle cell_area, out int x_offset, out int y_offset, out int width, out int height)
	{
		int calc_width = (int) this.Xpad * 2 + 100;
		int calc_height = (int) this.Ypad * 2 + 10;

		width = calc_width;
		height = calc_height;

		x_offset = 0;
		y_offset = 0;
		if (!cell_area.Equals (Rectangle.Zero)) {
			x_offset = (int) (this.Xalign * (cell_area.Width - calc_width));
			x_offset = Math.Max (x_offset, 0);
			
			y_offset = (int) (this.Yalign * (cell_area.Height - calc_height));
			y_offset = Math.Max (y_offset, 0);
		}
	}

	protected override void OnRender (Cairo.Context cr, Widget widget, Rectangle background_area, Rectangle cell_area, CellRendererState flags)
	{
		int x = (int) (cell_area.X + this.Xpad);
		int y = (int) (cell_area.Y + this.Ypad);
		int width = (int) (cell_area.Width - this.Xpad * 2);
		int height = (int) (cell_area.Height - this.Ypad * 2);

		widget.StyleContext.Save ();
		widget.StyleContext.AddClass ("trough");
		widget.StyleContext.RenderBackground (cr, x, y, width, height);
		widget.StyleContext.RenderFrame (cr, x, y, width, height);
		
		Border padding = widget.StyleContext.GetPadding (StateFlags.Normal);
		x += padding.Left;
		y += padding.Top;
		width -= padding.Left + padding.Right;
		height -= padding.Top + padding.Bottom;

		widget.StyleContext.Restore ();
		
		widget.StyleContext.Save ();
		widget.StyleContext.AddClass ("progressbar");
		widget.StyleContext.RenderActivity (cr, x, y, (int) (width * Percentage), height);
		widget.StyleContext.Restore ();
	}
}

public class Driver : Gtk.Window
{
	public static void Main ()
	{
		Gtk.Application.Init ();
		new Driver ();
		Gtk.Application.Run ();
	}

	ListStore liststore;
	
	public Driver () : base ("CustomCellRenderer")
	{
		DefaultSize = new Size (150, 100);
		this.DeleteEvent += new DeleteEventHandler (window_delete);

		liststore = new ListStore (typeof (float), typeof (string));
		liststore.AppendValues (0.5f, "50%");

		TreeView view = new TreeView (liststore);

		view.AppendColumn ("Progress", new CellRendererText (), "text", 1);
		view.AppendColumn ("Progress", new CustomCellRenderer (), "percent", 0);
		
		this.Add (view);
		this.ShowAll ();

		GLib.Timeout.Add (50, new GLib.TimeoutHandler (update_percent));
	}

	bool increasing = true;
	bool update_percent ()
	{
		TreeIter iter;
		liststore.GetIterFirst (out iter);
		float perc = (float) liststore.GetValue (iter, 0);

		if ((perc > 0.99) || (perc < 0.01 && perc > 0)) {
			increasing = !increasing;
		}

		if (increasing)
			perc += 0.01f;
		else
			perc -= 0.01f;

		liststore.SetValue (iter, 0, perc);
		liststore.SetValue (iter, 1, Convert.ToInt32 (perc * 100) + "%");

		return true;
	}

	void window_delete (object obj, DeleteEventArgs args)
	{
		Gtk.Application.Quit ();
		args.RetVal = true;
	}
}