Allow widgets to get the same size.

This is an initial implementation, it still needs quite some extra work,
which will be postponed until 1.7.

src/gui/widgets/widget.hpp

@@ -42,6 +42,7 @@ class twidget
 	, public virtual tevent_executor
 {
 	friend class tdebug_layout_graph;
+	friend class twindow; // needed for modifying the layout_size.
 
 public:
 	twidget()

src/gui/widgets/window.cpp

@@ -31,7 +31,6 @@
 #include "titlescreen.hpp"
 #include "video.hpp"
 
-
 namespace gui2{
 
 unsigned twindow::sunset_ = 0;
@@ -116,6 +115,7 @@ twindow::twindow(CVideo& video,
 	, easy_close_(false)
 	, easy_close_blocker_()
 	, escape_disabled_(false)
+	, linked_size_()
 	, dirty_list_()
 #ifdef DEBUG_WINDOW_LAYOUT_GRAPHS
 	, debug_layout_(new tdebug_layout_graph(this))
@@ -437,6 +437,23 @@ void twindow::remove_easy_close_blocker(const std::string& id)
 		easy_close_blocker_.end());
 }
 
+void twindow::init_linked_size_group(const std::string& id,
+		const bool fixed_width, const bool fixed_height)
+{
+	assert(fixed_width || fixed_height);
+	assert(linked_size_.find(id) == linked_size_.end());
+
+	linked_size_[id] = tlinked_size(fixed_width, fixed_height);
+}
+
+void twindow::add_linked_widget(const std::string& id, twidget* widget)
+{
+	assert(widget);
+	assert(linked_size_.find(id) != linked_size_.end());
+		
+	linked_size_[id].widgets.push_back(widget);
+}
+
 void twindow::layout()
 {
 	/**** Initialize and get initial size. *****/
@@ -460,6 +477,45 @@ void twindow::layout()
 	const int maximum_height = automatic_placement_ ?
 			settings::screen_height :  h_(variables);
 
+	/**
+	 * @todo Need to document this new feature in the size algorithm. Also the
+	 * fixed size only works when a widget doesn't get a second layout phase.
+	 */
+	// evaluate the group sizes
+	typedef std::pair<const std::string, tlinked_size> hack;
+	foreach(hack& linked_size, linked_size_) {
+
+		tpoint max_size(0, 0);
+
+		// Determine the maximum size.
+		foreach(twidget* widget, linked_size.second.widgets) {
+
+			const tpoint size = widget->get_best_size();
+
+			if(size.x > max_size.x) {
+				max_size.x = size.x;
+			}
+			if(size.y > max_size.y) {
+				max_size.y = size.y;
+			}
+		}
+
+		// Set the maximum size.
+		foreach(twidget* widget, linked_size.second.widgets) {
+
+			tpoint size = widget->get_best_size();
+
+			if(linked_size.second.width) {
+				size.x = max_size.x;
+			}
+			if(linked_size.second.height) {
+				size.y = max_size.y;
+			}
+
+			widget->set_layout_size(size);
+		}
+	}
+
 	tpoint size = get_best_size();
 	generate_dot_file("get_initial_best_size", LAYOUT);
 

src/gui/widgets/window.hpp

@@ -50,7 +50,9 @@ class twindow : public tpanel, public tevent_handler
 
 	// Wants to use layout().
 	friend class tmessage;
+
 public:
+
 	twindow(CVideo& video,
 		tformula<unsigned>x,
 		tformula<unsigned>y,
@@ -242,6 +244,31 @@ public:
 	void set_escape_disabled(const bool escape_disabled)
 		{ escape_disabled_ = escape_disabled; }
 
+	/**
+	 * Initializes a linked size group.
+	 *
+	 * Note at least one of fixed_width or fixed_height must be true.
+	 *
+	 * @param id                  The id of the group.
+	 * @param fixed_width         Does the group have a fixed width?
+	 * @param fixed_height        Does the group have a fixed height?
+	 */
+	void init_linked_size_group(const std::string& id,
+			const bool fixed_width, const bool fixed_height);
+
+	/**
+	 * Adds a widget to a linked size group.
+	 *
+	 * The group needs to exist, which is done by calling
+	 * init_linked_size_group. A widget may only be member of one group.
+	 * @todo There's no way to remove a widget from the list. 
+	 * @todo Untested if a new widget is added after showing the widgets.
+	 *
+	 * @param id                  The id of the group.
+	 * @param widget              The widget to add to the group.
+	 */
+	void add_linked_widget(const std::string& id, twidget* widget);
+
 	/***** ***** ***** setters / getters for members ***** ****** *****/
 
 	/**
@@ -358,6 +385,35 @@ private:
 	 */
 	static unsigned sunset_;
 
+	/**
+	 * Helper struct to force widgets the have the same size.
+	 *
+	 * Widget which are linked will get the same width and/or height. This
+	 * can especialy be usefull for listboxes, but can also be used for other
+	 * applications.
+	 */
+	struct tlinked_size
+	{
+		tlinked_size(const bool width = false, const bool height = false)
+			: widgets()
+			, width(width)
+			, height(height)
+		{
+		}
+
+		/** The widgets linked. */
+		std::vector<twidget*> widgets;
+
+		/** Link the widgets in the width? */
+		bool width;
+
+		/** Link the widgets in the height? */
+		bool height;
+	};
+	
+	/** List of the widgets, whose size are linked together. */
+	std::map<std::string, tlinked_size> linked_size_;
+
 	/** Layouts the window. */
 	void layout();