From d42c3fce150f7285e9aaec6990b03ed8858a223b Mon Sep 17 00:00:00 2001
From: Mark de Wever <koraq@xs4all.nl>
Date: Fri, 25 Jul 2008 19:10:49 +0000
Subject: [PATCH] Add a callback when the selection in a listbox changes.

---
 src/gui/widgets/listbox.cpp |  7 ++++++-
 src/gui/widgets/listbox.hpp | 15 ++++++++++++++-
 2 files changed, 20 insertions(+), 2 deletions(-)

diff --git a/src/gui/widgets/listbox.cpp b/src/gui/widgets/listbox.cpp
index 9b6790cc2c5..22ebdc4db41 100644
--- a/src/gui/widgets/listbox.cpp
+++ b/src/gui/widgets/listbox.cpp
@@ -87,6 +87,7 @@ tlistbox::tlistbox() :
 	list_rect_(),
 	list_background_(),
 	best_spacer_size_(0, 0),
+	callback_value_change_(NULL),
 	rows_()
 {
 }
@@ -173,7 +174,11 @@ bool tlistbox::list_row_selected(const size_t row, twidget* caller)
 	assert(rows_[row].grid());
 	if(rows_[row].grid()->has_widget(caller)) {
 
-		if(!select_row(row, !rows_[row].get_selected())) {
+		if(select_row(row, !rows_[row].get_selected())) {
+			if(callback_value_change_) {
+				callback_value_change_(this);
+			}
+		} else {
 			// if not allowed to deselect reselect.
 			tselectable_* selectable = dynamic_cast<tselectable_*>(caller);
 			assert(selectable);
diff --git a/src/gui/widgets/listbox.hpp b/src/gui/widgets/listbox.hpp
index a8c52f93fa0..9c85f49e6fc 100644
--- a/src/gui/widgets/listbox.hpp
+++ b/src/gui/widgets/listbox.hpp
@@ -57,13 +57,19 @@ public:
 	 */
 	void list_item_selected(twidget* caller);
 
+	/***** ***** ***** setters / getters for members ***** ****** *****/
+
+	void set_callback_value_change(void (*callback) (twidget* caller))
+		{ callback_value_change_ = callback; }
+
 private:
 
 	/**
 	 * Helper for list_item_selected().
 	 *
 	 * Tries to sets the selected state for the row, but only if it contains the
-	 * wanted widget.
+	 * wanted widget. NOTE this function assumes the event was triggered by the
+	 * user and calls the callback handler.
 	 *
 	 * @param row                    The row to test.
 	 * @param caller                 The widget to look for.
@@ -289,6 +295,13 @@ private:
 	/** The best size for the spacer, if not set it's calculated. */
 	tpoint best_spacer_size_;
 
+	/**
+	 * This callback is used when the selection is chnaged due to a user event.
+	 * The name is not fully appropriate for the event but it's choosen to be
+	 * generic.
+	 */
+	void (*callback_value_change_) (twidget* caller);
+
 	class trow {
 
 	public: