From fef09a8d2fe38dcc8fd3beff3e132f945a4d4c8a Mon Sep 17 00:00:00 2001
From: Mikko Rasa <tdb@tdb.fi>
Date: Sun, 16 Jun 2013 15:03:48 +0300
Subject: [PATCH] Support widget expansion in linear layouts

---
 source/arrangement.cpp       | 15 ++++++++++++++-
 source/arrangement.h         |  1 +
 source/lineararrangement.cpp | 19 +++++++++++++++++++
 source/lineararrangement.h   |  1 +
 4 files changed, 35 insertions(+), 1 deletion(-)

diff --git a/source/arrangement.cpp b/source/arrangement.cpp
index 581e6b4..9982691 100644
--- a/source/arrangement.cpp
+++ b/source/arrangement.cpp
@@ -45,7 +45,8 @@ void Arrangement::add_constraint(Widget &wdg, Layout::ConstraintType type, Side
 void Arrangement::add_constraint(Widget &wdg, Layout::ConstraintType type, const Edge &edge)
 {
 	for(list<Widget *>::const_iterator i=edge.widgets.begin(); i!=edge.widgets.end(); ++i)
-		layout.add_constraint(wdg, type, **i);
+		if(*i!=&wdg)
+			layout.add_constraint(wdg, type, **i);
 }
 
 Layout::ConstraintType Arrangement::get_order_constraint(Side s, bool slack)
@@ -95,5 +96,17 @@ void Arrangement::Edge::add(Widget &wdg, bool algn)
 	aligned = algn;
 }
 
+void Arrangement::Edge::align()
+{
+	if(aligned || widgets.empty())
+		return;
+
+	list<Widget *>::iterator second = widgets.begin();
+	++second;
+
+	widgets.erase(second, widgets.end());
+	aligned = true;
+}
+
 } // namespace GLtk
 } // namespace Msp
diff --git a/source/arrangement.h b/source/arrangement.h
index fc3ec82..f323a9b 100644
--- a/source/arrangement.h
+++ b/source/arrangement.h
@@ -38,6 +38,7 @@ protected:
 		bool empty() { return widgets.empty(); }
 		void clear();
 		void add(Widget &, bool);
+		void align();
 	};
 
 	Layout &layout;
diff --git a/source/lineararrangement.cpp b/source/lineararrangement.cpp
index 891b858..9e6441a 100644
--- a/source/lineararrangement.cpp
+++ b/source/lineararrangement.cpp
@@ -21,6 +21,19 @@ void LinearArrangement::split()
 	gravity = primary;
 }
 
+void LinearArrangement::expand()
+{
+	if(gravity==primary)
+		throw arrangement_error("already split");
+	if(edges[primary].empty())
+		throw arrangement_error("no widgets");
+
+	add_constraint(*edges[primary].widgets.front(), get_align_constraint(primary), primary);
+	layout.set_expand(*edges[primary].widgets.front(), false, true);
+	edges[primary].align();
+	gravity = primary;
+}
+
 void LinearArrangement::process_widget(Widget &wdg, Side side, bool aligned)
 {
 	if(side==opposite)
@@ -52,9 +65,15 @@ void LinearArrangement::finish_slot()
 LinearArrangement::Loader::Loader(LinearArrangement &c):
 	DataFile::ObjectLoader<LinearArrangement>(c)
 {
+	add("expand", &Loader::expand);
 	add("split", &Loader::split);
 }
 
+void LinearArrangement::Loader::expand()
+{
+	obj.expand();
+}
+
 void LinearArrangement::Loader::split()
 {
 	obj.split();
diff --git a/source/lineararrangement.h b/source/lineararrangement.h
index 571e279..3fd5ef7 100644
--- a/source/lineararrangement.h
+++ b/source/lineararrangement.h
@@ -15,6 +15,7 @@ public:
 	public:
 		Loader(LinearArrangement &);
 	private:
+		void expand();
 		void split();
 	};
 
-- 
2.43.0