Introduce ESelectable and EFocusTracker.

EFocusTracker tracks the input focus within a window and helps keep
the sensitivity of "selectable" actions in the main menu up-to-date.
Selectable actions include Cut, Copy, Paste, Select All and Delete.

EFocusTracker has built-in support for widgets that implement the
GtkEditable interface such as GtkEntry and GtkTextView.  It also
supports custom widgets that implement the ESelectable interface,
which is a subset of GtkEditable and can apply to anything that
displays selectable content (esp. tree views and ETables).

This commit integrates EFocusTracker with EShellWindow, CompEditor,
EMsgComposer, and ESignatureManager.

It also bumps the GtkHTML requirement to 2.29.5 to utilize the new
GtkhtmlEditor:html constructor property.

1 files changed, 133 insertions, 0 deletions

diff --git a/widgets/misc/e-selectable.c b/widgets/misc/e-selectable.c
new file mode 100644
index 0000000000..95cd2bb06f
--- /dev/null
+++ b/widgets/misc/e-selectable.c
@@ -0,0 +1,133 @@
+/*
+ * e-selectable.c
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) version 3.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with the program; if not, see <http://www.gnu.org/licenses/>
+ *
+ *
+ * Copyright (C) 1999-2008 Novell, Inc. (www.novell.com)
+ *
+ */
+
+#include "e-selectable.h"
+
+GType
+e_selectable_get_type (void)
+{
+	static GType type = 0;
+
+	if (G_UNLIKELY (type == 0)) {
+		static const GTypeInfo type_info = {
+			sizeof (ESelectableInterface),
+			(GBaseInitFunc) NULL,
+			(GBaseFinalizeFunc) NULL,
+			(GClassInitFunc) NULL,
+			(GClassFinalizeFunc) NULL,
+			NULL,  /* class_data */
+			0,     /* instance_size */
+			0,     /* n_preallocs */
+			(GInstanceInitFunc) NULL,
+			NULL   /* value_table */
+		};
+
+		type = g_type_register_static (
+			G_TYPE_INTERFACE, "ESelectable", &type_info, 0);
+
+		g_type_interface_add_prerequisite (type, G_TYPE_OBJECT);
+	}
+
+	return type;
+}
+
+void
+e_selectable_update_actions (ESelectable *selectable,
+                             EFocusTracker *focus_tracker,
+                             GdkAtom *clipboard_targets,
+                             gint n_clipboard_targets)
+{
+	ESelectableInterface *interface;
+
+	g_return_if_fail (E_IS_SELECTABLE (selectable));
+
+	interface = E_SELECTABLE_GET_INTERFACE (selectable);
+	g_return_if_fail (interface->update_actions != NULL);
+
+	return interface->update_actions (
+		selectable, focus_tracker,
+		clipboard_targets, n_clipboard_targets);
+}
+
+void
+e_selectable_cut_clipboard (ESelectable *selectable)
+{
+	ESelectableInterface *interface;
+
+	g_return_if_fail (E_IS_SELECTABLE (selectable));
+
+	interface = E_SELECTABLE_GET_INTERFACE (selectable);
+
+	if (interface->cut_clipboard != NULL)
+		interface->cut_clipboard (selectable);
+}
+
+void
+e_selectable_copy_clipboard (ESelectable *selectable)
+{
+	ESelectableInterface *interface;
+
+	g_return_if_fail (E_IS_SELECTABLE (selectable));
+
+	interface = E_SELECTABLE_GET_INTERFACE (selectable);
+
+	if (interface->copy_clipboard != NULL)
+		interface->copy_clipboard (selectable);
+}
+
+void
+e_selectable_paste_clipboard (ESelectable *selectable)
+{
+	ESelectableInterface *interface;
+
+	g_return_if_fail (E_IS_SELECTABLE (selectable));
+
+	interface = E_SELECTABLE_GET_INTERFACE (selectable);
+
+	if (interface->paste_clipboard != NULL)
+		interface->paste_clipboard (selectable);
+}
+
+void
+e_selectable_delete_selection (ESelectable *selectable)
+{
+	ESelectableInterface *interface;
+
+	g_return_if_fail (E_IS_SELECTABLE (selectable));
+
+	interface = E_SELECTABLE_GET_INTERFACE (selectable);
+
+	if (interface->delete_selection != NULL)
+		interface->delete_selection (selectable);
+}
+
+void
+e_selectable_select_all (ESelectable *selectable)
+{
+	ESelectableInterface *interface;
+
+	g_return_if_fail (E_IS_SELECTABLE (selectable));
+
+	interface = E_SELECTABLE_GET_INTERFACE (selectable);
+
+	if (interface->select_all != NULL)
+		interface->select_all (selectable);
+}