Add FreeLayout layout, which resizes its children to their sizeHint() whenever it is invalidated. Useful for desktop-like workspaces so that widgets can be agnostic of whether they are being used in a panel or a 'constraint free' area.

svn path=/trunk/KDE/kdebase/workspace/libs/plasma/; revision=710761

widgets/freelayout.cpp

@@ -0,0 +1,62 @@
+
+#include "freelayout.h"
+
+using namespace Plasma;
+
+class FreeLayout::Private
+{
+public:
+    QList<LayoutItem*> children;
+    QRectF geometry;
+};
+
+FreeLayout::FreeLayout(LayoutItem *parent)
+    : Layout(parent)
+    , d(new Private)
+{
+}
+Qt::Orientations FreeLayout::expandingDirections() const
+{
+    return Qt::Horizontal | Qt::Vertical;
+}
+void FreeLayout::addItem(LayoutItem *item)
+{
+    d->children << item;
+    item->setManagingLayout(this);
+}
+void FreeLayout::removeItem(LayoutItem *item)
+{
+    d->children.removeAll(item);
+}
+int FreeLayout::indexOf(LayoutItem *item) const
+{
+    return d->children.indexOf(item);
+}
+LayoutItem * FreeLayout::itemAt(int i) const
+{
+    return d->children[i];
+}
+int FreeLayout::count() const
+{
+    return d->children.count();
+}
+LayoutItem * FreeLayout::takeAt(int i) 
+{
+    return d->children.takeAt(i);
+}
+void FreeLayout::setGeometry(const QRectF& geometry)
+{
+    foreach( LayoutItem *child , d->children ) {
+        child->setGeometry( QRectF(child->geometry().topLeft(),child->sizeHint()) );
+    }
+    d->geometry = geometry;
+}
+QRectF FreeLayout::geometry() const
+{
+    return d->geometry;
+}
+QSizeF FreeLayout::sizeHint() const
+{
+    return maximumSize();
+}
+

widgets/freelayout.h

@@ -0,0 +1,67 @@
+/*
+ *   Copyright 2007 by Robert Knight <robertknight@gmail.com>
+ *
+ *   This program is free software; you can redistribute it and/or modify
+ *   it under the terms of the GNU Library General Public License version 2 as
+ *   published by the Free Software Foundation
+ *
+ *   This program 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 Library General Public
+ *   License along with this program; if not, write to the
+ *   Free Software Foundation, Inc.,
+ *   51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+ */
+
+#ifndef PLASMA_FREE_LAYOUT
+#define PLASMA_FREE_LAYOUT
+
+#include <QtCore/QList>
+
+#include <plasma/plasma_export.h>
+#include <plasma/widgets/layout.h>
+
+namespace Plasma
+{
+
+/**
+ * The FreeLayout class is a layout for use in desktop-like workspaces where
+ * I items can be moved around freely and applets and widgets are allowed
+ * to determine their own size.
+ *
+ * Whenever this layout is updated, all child items are resized to
+ * their sizeHint() and left in their existing positions.
+ */
+class PLASMA_EXPORT FreeLayout : public Layout
+{
+    public:
+        
+        /**
+         * Creates a new free layout
+         */
+        explicit FreeLayout(LayoutItem *parent = 0);
+
+        // reimplemented from Layout
+        virtual void addItem(LayoutItem *l);
+        virtual void removeItem(LayoutItem *l);
+        virtual int indexOf(LayoutItem *l) const;
+        virtual LayoutItem *itemAt(int i) const;
+        virtual LayoutItem *takeAt(int i);
+        virtual Qt::Orientations expandingDirections() const;
+        virtual QRectF geometry() const;
+        virtual void setGeometry(const QRectF& geometry);
+        virtual int count() const;
+
+        virtual QSizeF sizeHint() const;
+
+    private:
+        class Private;
+        Private *const d;
+};
+
+}
+
+#endif /* PLASMA_FREE_LAYOUT */