From: Mikko Rasa <tdb@tdb.fi>
Date: Tue, 27 Nov 2012 21:58:07 +0000 (+0200)
Subject: Add autosizing for panels
X-Git-Url: http://git.tdb.fi/?a=commitdiff_plain;h=e291dcf478052c771d85089409f9bc22a4c8ab93;p=libs%2Fgltk.git

Add autosizing for panels

It still does a lot of unnecessary layout updates, but seems to work at
least in basic cases.
---

diff --git a/source/layout.cpp b/source/layout.cpp
index f89e407..ccd0283 100644
--- a/source/layout.cpp
+++ b/source/layout.cpp
@@ -221,19 +221,27 @@ void Layout::set_expand(Widget &wdg, bool h, bool v)
 
 void Layout::update()
 {
-	solve_constraints(HORIZONTAL);
-	solve_constraints(VERTICAL);
+	solve_constraints(HORIZONTAL, UPDATE);
+	solve_constraints(VERTICAL, UPDATE);
 
 	for(list<Slot *>::iterator i=slots.begin(); i!=slots.end(); ++i)
 		(*i)->widget.set_geometry((*i)->geom);
 }
 
-void Layout::solve_constraints(int dir)
+void Layout::autosize()
+{
+	solve_constraints(HORIZONTAL, AUTOSIZE);
+	solve_constraints(VERTICAL, AUTOSIZE);
+
+	container->set_size(autosize_geom.w, autosize_geom.h);
+}
+
+void Layout::solve_constraints(int dir, SolveMode mode)
 {
 	Pointers &ptrs = pointers[dir&VERTICAL];
 
 	const Geometry &geom = container->get_geometry();
-	if(geom.*(ptrs.dim)<margin.*(ptrs.low_margin)+margin.*(ptrs.high_margin))
+	if(mode==UPDATE && geom.*(ptrs.dim)<margin.*(ptrs.low_margin)+margin.*(ptrs.high_margin))
 		return;
 
 	/* Set up a linear program to solve the constraints.  The program matrix has
@@ -244,8 +252,17 @@ void Layout::solve_constraints(int dir)
 	float weight = slots.size();
 	for(list<Slot *>::iterator i=slots.begin(); i!=slots.end(); ++i)
 	{
-		linprog.get_objective_row()[(*i)->index*5] = ((*i)->*(ptrs.packing)).gravity/weight;
-		linprog.get_objective_row()[(*i)->index*5+1] = (((*i)->*(ptrs.packing)).expand ? weight : -1);
+		LinearProgram::Row objective = linprog.get_objective_row();
+		if(mode==AUTOSIZE)
+		{
+			objective[(*i)->index*5] = -1;
+			objective[(*i)->index*5+1] = -1;
+		}
+		else
+		{
+			objective[(*i)->index*5] = ((*i)->*(ptrs.packing)).gravity/weight;
+			objective[(*i)->index*5+1] = (((*i)->*(ptrs.packing)).expand ? weight : -1);
+		}
 
 		{
 			// Prevent the widget from going past the container's low edge.
@@ -255,6 +272,7 @@ void Layout::solve_constraints(int dir)
 			row.back() = margin.*(ptrs.low_margin);
 		}
 
+		if(mode==UPDATE)
 		{
 			// Prevent the widget from going past the container's high edge.
 			LinearProgram::Row row = linprog.add_row();
@@ -296,10 +314,22 @@ void Layout::solve_constraints(int dir)
 	if(!linprog.solve())
 		return;
 
-	for(list<Slot *>::iterator i=slots.begin(); i!=slots.end(); ++i)
+	if(mode==AUTOSIZE)
 	{
-		(*i)->geom.*(ptrs.pos) = linprog.get_variable((*i)->index*5);
-		(*i)->geom.*(ptrs.dim) = linprog.get_variable((*i)->index*5+1);
+		autosize_geom.*(ptrs.dim) = 0;
+		for(list<Slot *>::iterator i=slots.begin(); i!=slots.end(); ++i)
+		{
+			int high_edge = linprog.get_variable((*i)->index*5)+linprog.get_variable((*i)->index*5+1);
+			autosize_geom.*(ptrs.dim) = max(autosize_geom.*(ptrs.dim), high_edge+margin.*(ptrs.high_margin));
+		}
+	}
+	else
+	{
+		for(list<Slot *>::iterator i=slots.begin(); i!=slots.end(); ++i)
+		{
+			(*i)->geom.*(ptrs.pos) = linprog.get_variable((*i)->index*5);
+			(*i)->geom.*(ptrs.dim) = linprog.get_variable((*i)->index*5+1);
+		}
 	}
 }
 
@@ -336,7 +366,10 @@ void Layout::Slot::autosize_changed()
 	if(autosize_geom.w<=geom.w && autosize_geom.h<=geom.h)
 		widget.set_geometry(geom);
 	else
+	{
+		layout.container->signal_autosize_changed.emit();
 		layout.update();
+	}
 }
 
 
diff --git a/source/layout.h b/source/layout.h
index cf63538..cbd763e 100644
--- a/source/layout.h
+++ b/source/layout.h
@@ -113,6 +113,12 @@ protected:
 		void autosize_changed();
 	};
 
+	enum SolveMode
+	{
+		UPDATE,
+		AUTOSIZE
+	};
+
 	class LinearProgram;
 	struct Pointers;
 
@@ -121,6 +127,7 @@ protected:
 	Sides margin;
 	unsigned row_spacing;
 	unsigned col_spacing;
+	Geometry autosize_geom;
 
 	static Pointers pointers[2];
 
@@ -146,9 +153,10 @@ public:
 	void set_expand(Widget &, bool, bool);
 
 	void update();
+	void autosize();
 
 protected:
-	void solve_constraints(int);
+	void solve_constraints(int, SolveMode);
 };
 
 } // namespace GLtk
diff --git a/source/panel.cpp b/source/panel.cpp
index 7876120..91e30cd 100644
--- a/source/panel.cpp
+++ b/source/panel.cpp
@@ -39,6 +39,12 @@ void Panel::set_layout(Layout *l)
 	layout = l;
 }
 
+void Panel::autosize()
+{
+	if(layout)
+		layout->autosize();
+}
+
 Panel::Child *Panel::create_child(Widget *wdg)
 {
 	return new Child(*this, wdg);
@@ -160,13 +166,19 @@ void Panel::on_geometry_change()
 void Panel::on_child_added(Widget &wdg)
 {
 	if(layout)
+	{
 		layout->add_widget(wdg);
+		signal_autosize_changed.emit();
+	}
 }
 
 void Panel::on_child_removed(Widget &wdg)
 {
 	if(layout)
+	{
 		layout->remove_widget(wdg);
+		signal_autosize_changed.emit();
+	}
 }
 
 void Panel::set_pointer_focus(Widget *wdg)
diff --git a/source/panel.h b/source/panel.h
index d3d1f79..a6a89c5 100644
--- a/source/panel.h
+++ b/source/panel.h
@@ -61,6 +61,7 @@ public:
 	virtual const char *get_class() const { return "panel"; }
 
 	void set_layout(Layout *);
+	virtual void autosize();
 
 protected:
 	virtual Child *create_child(Widget *);