Add Layout machanism.

4 files changed, 303 insertions, 1 deletions

diff --git a/plugingui/Makefile.am.plugingui b/plugingui/Makefile.am.plugingui
index b1698e4..e2969f0 100644
--- a/plugingui/Makefile.am.plugingui
+++ b/plugingui/Makefile.am.plugingui
@@ -22,6 +22,7 @@ PLUGIN_GUI_SOURCES = \
 	$(top_srcdir)/plugingui/checkbox.cc \
 	$(top_srcdir)/plugingui/slider.cc \
 	$(top_srcdir)/plugingui/scrollbar.cc \
+	$(top_srcdir)/plugingui/layout.cc \
 	$(top_srcdir)/plugingui/listbox.cc \
 	$(top_srcdir)/plugingui/listboxthin.cc \
 	$(top_srcdir)/plugingui/listboxbasic.cc \
diff --git a/plugingui/layout.cc b/plugingui/layout.cc
new file mode 100644
index 0000000..f12887e
--- /dev/null
+++ b/plugingui/layout.cc
@@ -0,0 +1,175 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/***************************************************************************
+ *            layout.cc
+ *
+ *  Sat Mar 21 15:12:36 CET 2015
+ *  Copyright 2015 Bent Bisballe Nyeng
+ *  deva@aasimon.org
+ ****************************************************************************/
+
+/*
+ *  This file is part of DrumGizmo.
+ *
+ *  DrumGizmo is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation; either version 2 of the License, or
+ *  (at your option) any later version.
+ *
+ *  DrumGizmo is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with DrumGizmo; if not, write to the Free Software
+ *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA.
+ */
+#include "layout.h"
+
+#include "widget.h"
+
+namespace GUI {
+
+LayoutItem::LayoutItem()
+	: parent(nullptr)
+{
+}
+
+LayoutItem::~LayoutItem()
+{
+	setLayoutParent(nullptr); // Will disconnect from layout if any.
+}
+
+void LayoutItem::setLayoutParent(Layout *p)
+{
+	if(this->parent)
+	{
+		this->parent->removeItem(this);
+	}
+
+	this->parent = p;
+}
+
+Layout::Layout(LayoutItem *parent)
+{
+	this->parent = parent;
+}
+
+void Layout::addItem(LayoutItem *item)
+{
+	items.push_back(item);
+	item->setLayoutParent(this);
+	layout();
+}
+
+void Layout::removeItem(LayoutItem *item)
+{
+	LayoutItemList::iterator i = items.begin();
+	while(i != items.end())
+	{
+		if(*i == item)
+		{
+			i = items.erase(i);
+			continue;
+		}
+		++i;
+	}
+
+	layout();
+}
+
+//
+// BoxLayout
+//
+
+BoxLayout::BoxLayout(LayoutItem *parent)
+	: Layout(parent)
+{
+	resize_children = true;
+}
+
+void BoxLayout::setResizeChildren(bool resize_children)
+{
+	this->resize_children = resize_children;
+}
+
+//
+// VBoxLayout
+//
+
+VBoxLayout::VBoxLayout(LayoutItem *parent)
+	: BoxLayout(parent), align(HALIGN_CENTER)
+{
+}
+
+void VBoxLayout::layout()
+{
+	size_t y = 0;
+	size_t w = parent->width();
+	size_t h = parent->height() / items.size();
+
+	LayoutItemList::iterator i = items.begin();
+	while(i != items.end())
+	{
+		LayoutItem *item = *i;
+		if(resize_children)item->resize(w, h);
+		item->move(0, y);
+		y += h;
+		++i;
+	}
+}
+
+//
+// HBoxLayout
+//
+
+HBoxLayout::HBoxLayout(LayoutItem *parent)
+	: BoxLayout(parent)
+	, align(VALIGN_CENTER)
+{
+}
+
+void HBoxLayout::layout()
+{
+	size_t w = parent->width() / items.size();
+	size_t h = parent->height();
+	size_t x = 0;
+
+	LayoutItemList::iterator i = items.begin();
+	while(i != items.end())
+	{
+		LayoutItem *item = *i;
+		if(resize_children)
+		{
+			item->resize(w, h);
+			item->move(x, 0);
+		}
+		else
+		{
+			size_t y = 0;
+			switch(align) {
+			case VALIGN_TOP:
+				y = 0;
+				break;
+			case VALIGN_CENTER:
+				y = (h / 2) - (item->height() / 2);
+				break;
+			case VALIGN_BOTTOM:
+				y = h - item->height();
+				break;
+			}
+
+			int diff = w - item->width();
+			item->move(x + diff / 2, y);
+		}
+		x += w;
+		++i;
+	}
+}
+
+void HBoxLayout::setVAlignment(alignment_t alignment)
+{
+	align = alignment;
+}
+
+} // GUI::
diff --git a/plugingui/layout.h b/plugingui/layout.h
new file mode 100644
index 0000000..a81f004
--- /dev/null
+++ b/plugingui/layout.h
@@ -0,0 +1,125 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/***************************************************************************
+ *            layout.h
+ *
+ *  Sat Mar 21 15:12:36 CET 2015
+ *  Copyright 2015 Bent Bisballe Nyeng
+ *  deva@aasimon.org
+ ****************************************************************************/
+
+/*
+ *  This file is part of DrumGizmo.
+ *
+ *  DrumGizmo is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation; either version 2 of the License, or
+ *  (at your option) any later version.
+ *
+ *  DrumGizmo is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with DrumGizmo; if not, write to the Free Software
+ *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA.
+ */
+#pragma once
+
+#include <list>
+#include <cstdlib>
+
+namespace GUI {
+
+class Layout;
+
+class LayoutItem {
+public:
+	LayoutItem();
+	virtual ~LayoutItem();
+
+	void setLayoutParent(Layout *parent);
+
+	virtual void resize(int width, int height) = 0;
+	virtual void move(size_t x, size_t y) = 0;
+	virtual size_t x() = 0;
+	virtual size_t y() = 0;
+	virtual size_t width() = 0;
+	virtual size_t height() = 0;
+
+private:
+	Layout *parent;
+};
+
+//! \brief Abtract Layout class.
+class Layout
+{
+public:
+	Layout(LayoutItem *parent);
+	virtual ~Layout() {}
+
+	virtual void addItem(LayoutItem *item);
+	virtual void removeItem(LayoutItem *item);
+
+	//! \brief Reimplement this method to create a new Layout rule.
+	virtual void layout() = 0;
+
+protected:
+	LayoutItem *parent;
+	typedef std::list<LayoutItem *> LayoutItemList;
+	LayoutItemList items;
+};
+
+//! \brief Abstract box layout
+class BoxLayout : public Layout {
+public:
+	BoxLayout(LayoutItem *parent);
+
+	//! \brief Set to false to only move the items, not scale them.
+	void setResizeChildren(bool resize_children);
+
+	virtual void layout() = 0;
+
+protected:
+	bool resize_children;
+};
+
+//! \brief A Layout that lays out its elements vertically.
+class VBoxLayout : public BoxLayout {
+public:
+	VBoxLayout(LayoutItem *parent);
+
+	typedef enum {
+		HALIGN_LEFT,
+		HALIGN_CENTER,
+		HALIGN_RIGHT,
+	} alignment_t;
+
+	void setHAlignment(alignment_t alignment);
+
+	virtual void layout();
+
+protected:
+	alignment_t align;
+};
+
+//! \brief A Layout that lays out its elements vertically.
+class HBoxLayout : public BoxLayout {
+public:
+	HBoxLayout(LayoutItem *parent);
+
+	typedef enum {
+		VALIGN_TOP,
+		VALIGN_CENTER,
+		VALIGN_BOTTOM,
+	} alignment_t;
+
+	void setVAlignment(alignment_t alignment);
+
+	virtual void layout();
+
+protected:
+	alignment_t align;
+};
+
+} // GUI::
diff --git a/plugingui/widget.h b/plugingui/widget.h
index 10b221a..32acd5c 100644
--- a/plugingui/widget.h
+++ b/plugingui/widget.h
@@ -29,6 +29,7 @@
 #include "guievent.h"
 #include "pixelbuffer.h"
 #include "notifier.h"
+#include "layout.h"
 
 #include <vector>
 
@@ -36,7 +37,7 @@ namespace GUI {
 
 class Window;
 
-class Widget : public Listener {
+class Widget : public Listener, LayoutItem {
 public:
 	Widget(Widget *parent);
 	virtual ~Widget();