menu_view: add character position to hover report

When setting the <dialog> attribute 'hover_details' to "yes", the hover
report features the character position of a hovered label.

Issue #3607
Issue #3629

repos/gems/src/app/menu_view/label_widget.h

@@ -88,12 +88,39 @@ struct Menu_view::Label_widget : Widget, Cursor::Glyph_position
 	/**
 	 * Cursor::Glyph_position interface
 	 */
-	 int xpos_of_glyph(unsigned at) const override
-	 {
-		Text const truncated_at(Cstring(_text.string(), at));
+	int xpos_of_glyph(unsigned at) const override
+	{
+		return _font->string_width(_text.string(), at).decimal();
+	}
 
-		return _font->string_width(truncated_at.string()).decimal();
-	 }
+	unsigned _char_index_at_xpos(unsigned xpos) const
+	{
+		return _font->index_at_xpos(_text.string(), xpos);
+	}
+
+	Hovered hovered(Point at) const override
+	{
+		Unique_id const hovered_id = Widget::hovered(at).unique_id;
+
+		if (!hovered_id.valid())
+			return Hovered { .unique_id = hovered_id, .detail = { } };
+
+		return { .unique_id = hovered_id,
+		         .detail    = { _char_index_at_xpos(at.x()) } };
+	}
+
+	void gen_hover_model(Xml_generator &xml, Point at) const override
+	{
+		if (_inner_geometry().contains(at)) {
+
+			xml.node(_type_name.string(), [&]() {
+
+				_gen_common_hover_attr(xml);
+
+				xml.attribute("at", _char_index_at_xpos(at.x()));
+			});
+		}
+	}
 
 	private:
 

repos/gems/src/app/menu_view/main.cc

@@ -126,7 +126,7 @@ struct Menu_view::Main
 
 	Attached_dataspace _input_ds { _env.rm(), _nitpicker.input()->dataspace() };
 
-	Widget::Unique_id _last_reported_hovered { };
+	Widget::Hovered _last_reported_hovered { };
 
 	void _handle_config();
 
@@ -208,7 +208,7 @@ void Menu_view::Main::_update_hover_report()
 		return;
 	}
 
-	Widget::Unique_id const new_hovered = _root_widget.hovered(_hovered_position);
+	Widget::Hovered const new_hovered = _root_widget.hovered(_hovered_position);
 
 	if (_last_reported_hovered != new_hovered) {
 

repos/gems/src/app/menu_view/widget.h

@@ -78,11 +78,30 @@ class Menu_view::Widget : List_model<Widget>::Element
 			 */
 			Unique_id() { }
 
-			bool operator != (Unique_id const &other) { return other.value != value; }
+			bool operator != (Unique_id const &other) const
+			{
+				return other.value != value;
+			}
 
 			bool valid() const { return value != 0; }
 		};
 
+		struct Hovered
+		{
+			/* widget */
+			Unique_id unique_id;
+
+			/* widget-local detail */
+			using Detail = String<16>;
+
+			Detail detail;
+
+			bool operator != (Hovered const &other) const
+			{
+				return (unique_id != other.unique_id) || (detail != other.detail);
+			}
+		};
+
 		static Name node_name(Xml_node node)
 		{
 			return node.attribute_value("name", Name(node.type()));
@@ -90,7 +109,7 @@ class Menu_view::Widget : List_model<Widget>::Element
 
 		static Animated_rect::Steps motion_steps() { return { 60 }; };
 
-	private:
+	protected:
 
 		Type_name const _type_name;
 		Name      const _name;
@@ -98,8 +117,6 @@ class Menu_view::Widget : List_model<Widget>::Element
 
 		Unique_id const _unique_id;
 
-	protected:
-
 		Widget_factory &_factory;
 
 		List_model<Widget> _children { };
@@ -169,6 +186,15 @@ class Menu_view::Widget : List_model<Widget>::Element
 				_animated_geometry.move_to(_geometry, motion_steps());
 		}
 
+		void _gen_common_hover_attr(Xml_generator &xml) const
+		{
+			xml.attribute("name",   _name.string());
+			xml.attribute("xpos",   geometry().x1());
+			xml.attribute("ypos",   geometry().y1());
+			xml.attribute("width",  geometry().w());
+			xml.attribute("height", geometry().h());
+		}
+
 	public:
 
 		Margin margin { 0, 0, 0, 0 };
@@ -233,16 +259,16 @@ class Menu_view::Widget : List_model<Widget>::Element
 		 *
 		 * This function is used to track changes of the hover model.
 		 */
-		virtual Unique_id hovered(Point at) const
+		virtual Hovered hovered(Point at) const
 		{
 			if (!_inner_geometry().contains(at))
-				return Unique_id();
+				return { };
 
-			Unique_id result = _unique_id;
+			Hovered result { .unique_id = _unique_id, .detail = { } };
 			_children.for_each([&] (Widget const &w) {
-				Unique_id const id = w.hovered(at - w.geometry().p1());
-				if (id.valid())
-					result = id;
+				Hovered const hovered = w.hovered(at - w.geometry().p1());
+				if (hovered.unique_id.valid())
+					result = hovered;
 			});
 
 			return result;
@@ -259,11 +285,7 @@ class Menu_view::Widget : List_model<Widget>::Element
 
 				xml.node(_type_name.string(), [&]() {
 
-					xml.attribute("name",   _name.string());
-					xml.attribute("xpos",   geometry().x1());
-					xml.attribute("ypos",   geometry().y1());
-					xml.attribute("width",  geometry().w());
-					xml.attribute("height", geometry().h());
+					_gen_common_hover_attr(xml);
 
 					_children.for_each([&] (Widget const &w) {
 						w.gen_hover_model(xml, at - w.geometry().p1()); });