New list class with iterators.

2000-07-03  Christopher James Lahey  <clahey@helixcode.com>

	* e-iterator.c, e-iterator.h, e-list-iterator.c,
	e-list-iterator.h, e-list.c, e-list.h: New list class with
	iterators.

	* e-canvas.c: Made it so that you don't get the same selection in
	the selection list more than once.

svn path=/trunk/; revision=3871

10 files changed, 726 insertions, 0 deletions

diff --git a/e-util/ChangeLog b/e-util/ChangeLog
index 638c588038..43e01a9bc8 100644
--- a/e-util/ChangeLog
+++ b/e-util/ChangeLog
@@ -1,3 +1,12 @@
+2000-07-03  Christopher James Lahey  <clahey@helixcode.com>
+
+	* e-iterator.c, e-iterator.h, e-list-iterator.c,
+	e-list-iterator.h, e-list.c, e-list.h: New list class with
+	iterators.
+
+	* e-canvas.c: Made it so that you don't get the same selection in
+	the selection list more than once.
+
 2000-07-01  Ettore Perazzoli  <ettore@helixcode.com>
 
 	* e-gui-utils.h: #include <libgnomeui/gnome-messagebox.h>.  It's
diff --git a/e-util/Makefile.am b/e-util/Makefile.am
index 0e9680dc3d..43998022b4 100644
--- a/e-util/Makefile.am
+++ b/e-util/Makefile.am
@@ -23,6 +23,12 @@ libeutil_la_SOURCES =			\
 	e-gui-utils.h			\
 	e-html-utils.c			\
 	e-html-utils.h			\
+	e-iterator.c			\
+	e-iterator.h			\
+	e-list.c			\
+	e-list.h			\
+	e-list-iterator.c		\
+	e-list-iterator.h		\
 	e-popup-menu.c			\
 	e-popup-menu.h			\
 	e-printable.c			\
diff --git a/e-util/e-canvas.c b/e-util/e-canvas.c
index 0da4dade28..4cb912283e 100644
--- a/e-util/e-canvas.c
+++ b/e-util/e-canvas.c
@@ -583,6 +583,7 @@ e_canvas_item_add_selection (GnomeCanvasItem *item, gpointer id)
 	ECanvas *canvas;
 	ECanvasSelectionInfo *info;
 	ECanvasItemSelectionFunc func;
+	GList *list;
 
 	g_return_if_fail(item != NULL);
 	g_return_if_fail(GNOME_IS_CANVAS_ITEM(item));
@@ -602,6 +603,24 @@ e_canvas_item_add_selection (GnomeCanvasItem *item, gpointer id)
 
 	flags = E_CANVAS_ITEM_SELECTION_SELECT | E_CANVAS_ITEM_SELECTION_CURSOR;
 
+	for (list = canvas->selection; list; list = g_list_next(list)) {
+		ECanvasSelectionInfo *search;
+		search = list->data;
+
+		if (search->item == item) {
+			ECanvasItemSelectionCompareFunc compare_func;
+			compare_func = gtk_object_get_data(GTK_OBJECT(search->item), "ECanvasItem::selection_compare_callback");
+
+			if (compare_func(search->item, search->id, id, 0) == 0) {
+				canvas->cursor = search;
+				func = gtk_object_get_data(GTK_OBJECT(item), "ECanvasItem::selection_callback");
+				if (func)
+					func(item, flags, search->id);
+				return;
+			}
+		}
+	}
+
 	info = g_new(ECanvasSelectionInfo, 1);
 	info->item = item;
 	info->id = id;
diff --git a/e-util/e-iterator.c b/e-util/e-iterator.c
new file mode 100644
index 0000000000..cff6fec946
--- /dev/null
+++ b/e-util/e-iterator.c
@@ -0,0 +1,169 @@
+/* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*- */
+/*
+ * Authors: 
+ *   Christopher James Lahey <clahey@umich.edu>
+ *
+ * Copyright (C) 2000 Helix Code, Inc.
+ * Copyright (C) 1999 The Free Software Foundation
+ */
+
+#include <config.h>
+#include <gtk/gtk.h>
+
+#include "e-iterator.h"
+
+#define ECI_CLASS(object) (E_ITERATOR_CLASS(GTK_OBJECT((object))->klass))
+
+static void e_iterator_init (EIterator *card);
+static void e_iterator_class_init (EIteratorClass *klass);
+
+#define PARENT_TYPE (gtk_object_get_type ())
+
+static GtkObjectClass *parent_class;
+
+enum {
+	INVALIDATE,
+	LAST_SIGNAL
+};
+
+static guint e_iterator_signals [LAST_SIGNAL] = { 0, };
+
+/**
+ * e_iterator_get_type:
+ * @void: 
+ * 
+ * Registers the &EIterator class if necessary, and returns the type ID
+ * associated to it.
+ * 
+ * Return value: The type ID of the &EIterator class.
+ **/
+GtkType
+e_iterator_get_type (void)
+{
+	static GtkType type = 0;
+
+	if (!type) {
+		GtkTypeInfo info = {
+			"EIterator",
+			sizeof (EIterator),
+			sizeof (EIteratorClass),
+			(GtkClassInitFunc) e_iterator_class_init,
+			(GtkObjectInitFunc) e_iterator_init,
+			NULL, /* reserved_1 */
+			NULL, /* reserved_2 */
+			(GtkClassInitFunc) NULL
+		};
+
+		type = gtk_type_unique (PARENT_TYPE, &info);
+	}
+
+	return type;
+}
+
+static void
+e_iterator_class_init (EIteratorClass *klass)
+{
+	GtkObjectClass *object_class;
+
+	object_class = GTK_OBJECT_CLASS(klass);
+
+	parent_class = gtk_type_class (PARENT_TYPE);
+
+	e_iterator_signals [INVALIDATE] =
+		gtk_signal_new ("invalidate",
+				GTK_RUN_LAST,
+				object_class->type,
+				GTK_SIGNAL_OFFSET (EIteratorClass, invalidate),
+				gtk_marshal_NONE__NONE,
+				GTK_TYPE_NONE, 0);
+
+	gtk_object_class_add_signals (object_class, e_iterator_signals, LAST_SIGNAL);
+
+	klass->invalidate = NULL;
+	klass->get        = NULL;
+	klass->reset      = NULL;
+	klass->next       = NULL;
+	klass->prev       = NULL;
+	klass->delete     = NULL;
+	klass->set        = NULL;
+	klass->is_valid   = NULL;
+}
+
+/**
+ * e_iterator_init:
+ */
+static void
+e_iterator_init (EIterator *card)
+{
+}
+
+/*
+ * Virtual functions: 
+ */
+const void *
+e_iterator_get      (EIterator *iterator)
+{
+	if (ECI_CLASS(iterator)->get)
+		return ECI_CLASS(iterator)->get(iterator);
+	else
+		return NULL;
+}
+
+void
+e_iterator_reset    (EIterator *iterator)
+{
+	if (ECI_CLASS(iterator)->reset)
+		ECI_CLASS(iterator)->reset(iterator);
+}
+
+gboolean
+e_iterator_next     (EIterator *iterator)
+{
+	if (ECI_CLASS(iterator)->next)
+		return ECI_CLASS(iterator)->next(iterator);
+	else
+		return FALSE;
+}
+
+gboolean
+e_iterator_prev     (EIterator *iterator)
+{
+	if (ECI_CLASS(iterator)->prev)
+		return ECI_CLASS(iterator)->prev(iterator);
+	else
+		return FALSE;
+}
+
+void
+e_iterator_delete   (EIterator *iterator)
+{
+	if (ECI_CLASS(iterator)->delete)
+		ECI_CLASS(iterator)->delete(iterator);
+}
+
+void
+e_iterator_set      (EIterator *iterator,
+			  const void    *object)
+{
+	if (ECI_CLASS(iterator)->set)
+		ECI_CLASS(iterator)->set(iterator, object);
+}
+
+gboolean
+e_iterator_is_valid (EIterator *iterator)
+{
+	if (ECI_CLASS(iterator)->is_valid)
+		return ECI_CLASS(iterator)->is_valid(iterator);
+	else
+		return FALSE;
+}
+
+void
+e_iterator_invalidate (EIterator *iterator)
+{
+	g_return_if_fail (iterator != NULL);
+	g_return_if_fail (E_IS_ITERATOR (iterator));
+
+	gtk_signal_emit (GTK_OBJECT (iterator),
+			 e_iterator_signals [INVALIDATE]);
+}
diff --git a/e-util/e-iterator.h b/e-util/e-iterator.h
new file mode 100644
index 0000000000..eb983e9da9
--- /dev/null
+++ b/e-util/e-iterator.h
@@ -0,0 +1,61 @@
+/* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*- */
+/*
+ * Authors:
+ *   Chris Lahey <clahey@helixcode.com>
+ *
+ * Copyright (C) 2000 Helix Code, Inc.
+ * Copyright (C) 1999 The Free Software Foundation
+ */
+
+#ifndef __E_ITERATOR_H__
+#define __E_ITERATOR_H__
+
+#include <time.h>
+#include <gtk/gtk.h>
+#include <stdio.h>
+
+#define E_TYPE_ITERATOR            (e_iterator_get_type ())
+#define E_ITERATOR(obj)            (GTK_CHECK_CAST ((obj), E_TYPE_ITERATOR, EIterator))
+#define E_ITERATOR_CLASS(klass)    (GTK_CHECK_CLASS_CAST ((klass), E_TYPE_ITERATOR, EIteratorClass))
+#define E_IS_ITERATOR(obj)         (GTK_CHECK_TYPE ((obj), E_TYPE_ITERATOR))
+#define E_IS_ITERATOR_CLASS(klass) (GTK_CHECK_CLASS_TYPE ((klass), E_TYPE_ITERATOR))
+
+typedef struct _EIterator EIterator;
+typedef struct _EIteratorClass EIteratorClass;
+
+struct _EIterator {
+	GtkObject object;
+};
+
+struct _EIteratorClass {
+	GtkObjectClass parent_class;
+
+	/* Signals */
+	void         (*invalidate) (EIterator *iterator);
+	
+	/* Virtual functions */
+	const void * (*get)        (EIterator *iterator);
+	void         (*reset)      (EIterator *iterator);
+	gboolean     (*next)       (EIterator *iterator);
+	gboolean     (*prev)       (EIterator *iterator);
+	void         (*delete)     (EIterator *iterator);
+	void         (*set)        (EIterator *iterator,
+				    const void    *object);
+	gboolean     (*is_valid)   (EIterator *iterator);
+};
+
+const void    *e_iterator_get        (EIterator *iterator);
+void           e_iterator_reset      (EIterator *iterator);
+gboolean       e_iterator_next       (EIterator *iterator);
+gboolean       e_iterator_prev       (EIterator *iterator);
+void           e_iterator_delete     (EIterator *iterator);
+void           e_iterator_set        (EIterator *iterator, 
+				      const void    *object);
+gboolean       e_iterator_is_valid   (EIterator *iterator);
+
+void           e_iterator_invalidate (EIterator *iterator);
+
+/* Standard Gtk function */
+GtkType        e_iterator_get_type   (void);
+
+#endif /* ! __E_ITERATOR_H__ */
diff --git a/e-util/e-list-iterator.c b/e-util/e-list-iterator.c
new file mode 100644
index 0000000000..19ebbef681
--- /dev/null
+++ b/e-util/e-list-iterator.c
@@ -0,0 +1,199 @@
+/* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*- */
+/*
+ * Authors: 
+ *   Christopher James Lahey <clahey@umich.edu>
+ *
+ * Copyright (C) 2000 Helix Code, Inc.
+ * Copyright (C) 1999 The Free Software Foundation
+ */
+
+#include <config.h>
+#include <gtk/gtk.h>
+
+#include "e-list-iterator.h"
+#include "e-list.h"
+
+static void e_list_iterator_init (EListIterator *list);
+static void e_list_iterator_class_init (EListIteratorClass *klass);
+
+static void e_list_iterator_invalidate (EIterator *iterator);
+static gboolean e_list_iterator_is_valid (EIterator *iterator);
+static void e_list_iterator_set      (EIterator *iterator,
+					   const void    *object);
+static void e_list_iterator_delete   (EIterator *iterator);
+static gboolean e_list_iterator_prev     (EIterator *iterator);
+static gboolean e_list_iterator_next     (EIterator *iterator);
+static void e_list_iterator_reset    (EIterator *iterator);
+static const void *e_list_iterator_get      (EIterator *iterator);
+static void e_list_iterator_destroy (GtkObject *object);
+
+#define PARENT_TYPE (e_iterator_get_type ())
+
+static GtkObjectClass *parent_class;
+#define PARENT_CLASS (E_LIST_ITERATOR_CLASS(parent_class))
+
+/**
+ * e_list_iterator_get_type:
+ * @void: 
+ * 
+ * Registers the &EListIterator class if necessary, and returns the type ID
+ * associated to it.
+ * 
+ * Return value: The type ID of the &EListIterator class.
+ **/
+GtkType
+e_list_iterator_get_type (void)
+{
+	static GtkType type = 0;
+
+	if (!type) {
+		GtkTypeInfo info = {
+			"EListIterator",
+			sizeof (EListIterator),
+			sizeof (EListIteratorClass),
+			(GtkClassInitFunc) e_list_iterator_class_init,
+			(GtkObjectInitFunc) e_list_iterator_init,
+			NULL, /* reserved_1 */
+			NULL, /* reserved_2 */
+			(GtkClassInitFunc) NULL
+		};
+
+		type = gtk_type_unique (PARENT_TYPE, &info);
+	}
+
+	return type;
+}
+
+static void
+e_list_iterator_class_init (EListIteratorClass *klass)
+{
+	GtkObjectClass *object_class;
+	EIteratorClass *iterator_class;
+
+	object_class = GTK_OBJECT_CLASS(klass);
+	iterator_class = E_ITERATOR_CLASS(klass);
+
+	parent_class = gtk_type_class (PARENT_TYPE);
+
+	object_class->destroy = e_list_iterator_destroy;
+
+	iterator_class->invalidate = e_list_iterator_invalidate;
+	iterator_class->get        = e_list_iterator_get;
+	iterator_class->reset      = e_list_iterator_reset;
+	iterator_class->next       = e_list_iterator_next;
+	iterator_class->prev       = e_list_iterator_prev;
+	iterator_class->delete     = e_list_iterator_delete;
+	iterator_class->set        = e_list_iterator_set;
+	iterator_class->is_valid   = e_list_iterator_is_valid;
+}
+
+
+
+/**
+ * e_list_iterator_init:
+ */
+static void
+e_list_iterator_init (EListIterator *list)
+{
+}
+
+EIterator *
+e_list_iterator_new (EList *list)
+{
+	EListIterator *iterator = gtk_type_new(e_list_iterator_get_type());
+
+	iterator->list = list;
+	gtk_object_ref(GTK_OBJECT(list));
+	iterator->iterator = list->list;
+
+	return E_ITERATOR(iterator);
+}
+
+/*
+ * Virtual functions: 
+ */
+static void
+e_list_iterator_destroy (GtkObject *object)
+{
+	EListIterator *iterator = E_LIST_ITERATOR(object);
+	e_list_remove_iterator(iterator->list, E_ITERATOR(iterator));
+	gtk_object_unref(GTK_OBJECT(iterator->list));
+}
+
+static const void *
+e_list_iterator_get      (EIterator *_iterator)
+{
+	EListIterator *iterator = E_LIST_ITERATOR(_iterator);
+	if (iterator->iterator)
+		return iterator->iterator->data;
+	else
+		return NULL;
+}
+
+static void
+e_list_iterator_reset    (EIterator *_iterator)
+{
+	EListIterator *iterator = E_LIST_ITERATOR(_iterator);
+	iterator->iterator = iterator->list->list;
+}
+
+static gboolean
+e_list_iterator_next     (EIterator *_iterator)
+{
+	EListIterator *iterator = E_LIST_ITERATOR(_iterator);
+	if (iterator->iterator)
+		iterator->iterator = g_list_next(iterator->iterator);
+	return (iterator->iterator != NULL);
+}
+
+static gboolean
+e_list_iterator_prev     (EIterator *_iterator)
+{
+	EListIterator *iterator = E_LIST_ITERATOR(_iterator);
+	if (iterator->iterator)
+		iterator->iterator = g_list_previous(iterator->iterator);
+	return (iterator->iterator != NULL);
+}
+
+static void
+e_list_iterator_delete   (EIterator *_iterator)
+{
+	EListIterator *iterator = E_LIST_ITERATOR(_iterator);
+	if (iterator->iterator) {
+		GList *temp = iterator->iterator->next;
+		if (iterator->list->free)
+			iterator->list->free(iterator->iterator->data, iterator->list->closure);
+		iterator->list->list = g_list_remove_link(iterator->list->list, iterator->iterator);
+		iterator->iterator = temp;
+		e_list_invalidate_iterators(iterator->list, E_ITERATOR(iterator));
+	}
+}
+
+static void
+e_list_iterator_set      (EIterator *_iterator,
+			       const void    *object)
+{
+	EListIterator *iterator = E_LIST_ITERATOR(_iterator);
+	if (iterator->iterator) {
+		if (iterator->list->free)
+			iterator->list->free(iterator->iterator->data, iterator->list->closure);
+		if (iterator->list->copy)
+			iterator->iterator->data = iterator->list->copy(object, iterator->list->closure);
+		else
+			iterator->iterator->data = (void *) object;
+	}
+}
+
+static gboolean
+e_list_iterator_is_valid (EIterator *_iterator)
+{
+	EListIterator *iterator = E_LIST_ITERATOR(_iterator);
+	return iterator->iterator != NULL;
+}
+
+static void
+e_list_iterator_invalidate (EIterator *_iterator)
+{
+	EListIterator *iterator = E_LIST_ITERATOR(_iterator);
+	iterator->iterator = NULL;
+}
diff --git a/e-util/e-list-iterator.h b/e-util/e-list-iterator.h
new file mode 100644
index 0000000000..a2b7d82988
--- /dev/null
+++ b/e-util/e-list-iterator.h
@@ -0,0 +1,44 @@
+/* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*- */
+/*
+ * Authors:
+ *   Chris Lahey <clahey@helixcode.com>
+ *
+ * Copyright (C) 2000 Helix Code, Inc.
+ * Copyright (C) 1999 The Free Software Foundation
+ */
+
+#ifndef __E_LIST_ITERATOR_H__
+#define __E_LIST_ITERATOR_H__
+
+typedef struct _EListIterator EListIterator;
+typedef struct _EListIteratorClass EListIteratorClass;
+
+#include <time.h>
+#include <gtk/gtk.h>
+#include <stdio.h>
+#include <e-util/e-iterator.h>
+#include <e-util/e-list.h>
+
+#define E_TYPE_LIST_ITERATOR            (e_list_iterator_get_type ())
+#define E_LIST_ITERATOR(obj)            (GTK_CHECK_CAST ((obj), E_TYPE_LIST_ITERATOR, EListIterator))
+#define E_LIST_ITERATOR_CLASS(klass)    (GTK_CHECK_CLASS_CAST ((klass), E_TYPE_LIST_ITERATOR, EListIteratorClass))
+#define E_IS_LIST_ITERATOR(obj)         (GTK_CHECK_TYPE ((obj), E_TYPE_LIST_ITERATOR))
+#define E_IS_LIST_ITERATOR_CLASS(klass) (GTK_CHECK_CLASS_TYPE ((klass), E_TYPE_LIST_ITERATOR))
+
+struct _EListIterator {
+	EIterator      parent;
+
+	EList         *list;
+	GList         *iterator;
+};
+
+struct _EListIteratorClass {
+	EIteratorClass parent_class;
+};
+
+EIterator *e_list_iterator_new      (EList *list);
+
+/* Standard Gtk function */
+GtkType    e_list_iterator_get_type (void);
+
+#endif /* ! __E_LIST_ITERATOR_H__ */
diff --git a/e-util/e-list.c b/e-util/e-list.c
new file mode 100644
index 0000000000..bc5769fb38
--- /dev/null
+++ b/e-util/e-list.c
@@ -0,0 +1,140 @@
+/* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*- */
+/*
+ * Authors: 
+ *   Christopher James Lahey <clahey@umich.edu>
+ *
+ * Copyright (C) 2000 Helix Code, Inc.
+ * Copyright (C) 1999 The Free Software Foundation
+ */
+
+#include <config.h>
+#include <gtk/gtk.h>
+
+#include "e-list.h"
+#include "e-list-iterator.h"
+
+#define ECL_CLASS(object) (E_LIST_CLASS(GTK_OBJECT((object))->klass))
+
+static void e_list_init (EList *list);
+static void e_list_class_init (EListClass *klass);
+static void e_list_destroy (GtkObject *object);
+
+#define PARENT_TYPE (gtk_object_get_type ())
+
+static GtkObjectClass *parent_class;
+
+/**
+ * e_list_get_type:
+ * @void: 
+ * 
+ * Registers the &EList class if necessary, and returns the type ID
+ * associated to it.
+ * 
+ * Return value: The type ID of the &EList class.
+ **/
+GtkType
+e_list_get_type (void)
+{
+	static GtkType type = 0;
+
+	if (!type) {
+		GtkTypeInfo info = {
+			"EList",
+			sizeof (EList),
+			sizeof (EListClass),
+			(GtkClassInitFunc) e_list_class_init,
+			(GtkObjectInitFunc) e_list_init,
+			NULL, /* reserved_1 */
+			NULL, /* reserved_2 */
+			(GtkClassInitFunc) NULL
+		};
+
+		type = gtk_type_unique (PARENT_TYPE, &info);
+	}
+
+	return type;
+}
+
+static void
+e_list_class_init (EListClass *klass)
+{
+	GtkObjectClass *object_class;
+
+	object_class = GTK_OBJECT_CLASS(klass);
+
+	parent_class = gtk_type_class (PARENT_TYPE);
+
+	object_class->destroy = e_list_destroy;
+}
+
+/**
+ * e_list_init:
+ */
+static void
+e_list_init (EList *list)
+{
+	list->list = NULL;
+	list->iterators = NULL;
+}
+
+EList *
+e_list_new          (EListCopyFunc copy, EListFreeFunc free, void *closure)
+{
+	EList *list = gtk_type_new(e_list_get_type());
+	list->copy    = copy;
+	list->free    = free;
+	list->closure = closure;
+	return list;
+}
+
+EIterator *
+e_list_get_iterator (EList *list)
+{
+	EIterator *iterator = e_list_iterator_new(list);
+	list->iterators = g_list_append(list->iterators, iterator);
+	return iterator;
+}
+
+int
+e_list_length (EList *list)
+{
+	return g_list_length(list->list);
+}
+
+void
+e_list_append       (EList *list, const void *data)
+{
+	e_list_invalidate_iterators(list, NULL);
+	if (list->copy)
+		list->list = g_list_append(list->list, list->copy(data, list->closure));
+	else
+		list->list = g_list_append(list->list, (void *) data);
+}
+
+void
+e_list_invalidate_iterators (EList *list, EIterator *skip)
+{
+	GList *iterators = list->iterators;
+	for (; iterators; iterators = iterators->next) {
+		if (iterators->data != skip) {
+			e_iterator_invalidate(E_ITERATOR(iterators->data));
+		}
+	}
+}
+
+void
+e_list_remove_iterator (EList *list, EIterator *iterator)
+{
+	list->iterators = g_list_remove(list->iterators, iterator);
+}
+
+/* 
+ * Virtual functions 
+ */
+static void
+e_list_destroy (GtkObject *object)
+{
+	EList *list = E_LIST(object);
+	g_list_foreach(list->list, (GFunc) list->free, list->closure);
+	g_list_free(list->list);
+}
diff --git a/e-util/e-list.h b/e-util/e-list.h
new file mode 100644
index 0000000000..545798fbf9
--- /dev/null
+++ b/e-util/e-list.h
@@ -0,0 +1,60 @@
+/* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*- */
+/*
+ * Authors:
+ *   Chris Lahey <clahey@helixcode.com>
+ *
+ * Copyright (C) 2000 Helix Code, Inc.
+ * Copyright (C) 1999 The Free Software Foundation
+ */
+
+#ifndef __E_LIST_H__
+#define __E_LIST_H__
+
+typedef struct _EList EList;
+typedef struct _EListClass EListClass;
+
+#include <time.h>
+#include <gtk/gtk.h>
+#include <stdio.h>
+#include <e-util/e-list-iterator.h>
+
+#define E_TYPE_LIST            (e_list_get_type ())
+#define E_LIST(obj)            (GTK_CHECK_CAST ((obj), E_TYPE_LIST, EList))
+#define E_LIST_CLASS(klass)    (GTK_CHECK_CLASS_CAST ((klass), E_TYPE_LIST, EListClass))
+#define E_IS_LIST(obj)         (GTK_CHECK_TYPE ((obj), E_TYPE_LIST))
+#define E_IS_LIST_CLASS(klass) (GTK_CHECK_CLASS_TYPE ((klass), E_TYPE_LIST))
+
+typedef void *(*EListCopyFunc) (const void *data, void *closure);
+typedef void (*EListFreeFunc) (void *data, void *closure);
+
+struct _EList {
+	GtkObject      object;
+	GList         *list;
+	GList         *iterators;
+	EListCopyFunc  copy;
+	EListFreeFunc  free;
+	void          *closure;
+};
+
+struct _EListClass {
+	GtkObjectClass parent_class;
+};
+
+EList     *e_list_new                  (EListCopyFunc  copy, 
+					EListFreeFunc  free,
+					void          *closure);
+EIterator *e_list_get_iterator         (EList         *list);
+void       e_list_append               (EList         *list,
+					const void    *data);
+int        e_list_length               (EList         *list);
+
+/* For iterators to call. */
+void       e_list_invalidate_iterators (EList         *list, 
+					EIterator     *skip);
+void       e_list_remove_iterator      (EList         *list,
+					EIterator     *iterator);
+
+/* Standard Gtk function */
+GtkType    e_list_get_type             (void);
+
+#endif /* ! __E_LIST_H__ */
diff --git a/widgets/misc/e-canvas.c b/widgets/misc/e-canvas.c
index 0da4dade28..4cb912283e 100644
--- a/widgets/misc/e-canvas.c
+++ b/widgets/misc/e-canvas.c
@@ -583,6 +583,7 @@ e_canvas_item_add_selection (GnomeCanvasItem *item, gpointer id)
 	ECanvas *canvas;
 	ECanvasSelectionInfo *info;
 	ECanvasItemSelectionFunc func;
+	GList *list;
 
 	g_return_if_fail(item != NULL);
 	g_return_if_fail(GNOME_IS_CANVAS_ITEM(item));
@@ -602,6 +603,24 @@ e_canvas_item_add_selection (GnomeCanvasItem *item, gpointer id)
 
 	flags = E_CANVAS_ITEM_SELECTION_SELECT | E_CANVAS_ITEM_SELECTION_CURSOR;
 
+	for (list = canvas->selection; list; list = g_list_next(list)) {
+		ECanvasSelectionInfo *search;
+		search = list->data;
+
+		if (search->item == item) {
+			ECanvasItemSelectionCompareFunc compare_func;
+			compare_func = gtk_object_get_data(GTK_OBJECT(search->item), "ECanvasItem::selection_compare_callback");
+
+			if (compare_func(search->item, search->id, id, 0) == 0) {
+				canvas->cursor = search;
+				func = gtk_object_get_data(GTK_OBJECT(item), "ECanvasItem::selection_callback");
+				if (func)
+					func(item, flags, search->id);
+				return;
+			}
+		}
+	}
+
 	info = g_new(ECanvasSelectionInfo, 1);
 	info->item = item;
 	info->id = id;