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# linearlayout.h Example File

declarative/cppextensions/qgraphicslayouts/qgraphicslinearlayout/linearlayout.h

     /****************************************************************************
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     ** This file is part of the examples of the Qt Toolkit.
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     #ifndef LINEARLAYOUT_H
     #define LINEARLAYOUT_H

     #include <qdeclarative.h>

     #include <QGraphicsLinearLayout>
     #include <QGraphicsLayoutItem>

     class GraphicsLinearLayoutStretchItemObject : public QObject, public QGraphicsLayoutItem
     {
         Q_OBJECT
         Q_INTERFACES(QGraphicsLayoutItem)
     public:
         GraphicsLinearLayoutStretchItemObject(QObject *parent = 0);

         virtual QSizeF sizeHint(Qt::SizeHint, const QSizeF &) const;
     };

     class LinearLayoutAttached;
     class GraphicsLinearLayoutObject : public QObject, public QGraphicsLinearLayout
     {
         Q_OBJECT
         Q_INTERFACES(QGraphicsLayout QGraphicsLayoutItem)

         Q_PROPERTY(QDeclarativeListProperty<QGraphicsLayoutItem> children READ children)
         Q_PROPERTY(Qt::Orientation orientation READ orientation WRITE setOrientation)
         Q_PROPERTY(qreal spacing READ spacing WRITE setSpacing)
         Q_PROPERTY(qreal contentsMargin READ contentsMargin WRITE setContentsMargin)
         Q_CLASSINFO("DefaultProperty", "children")
     public:
         GraphicsLinearLayoutObject(QObject * = 0);
         ~GraphicsLinearLayoutObject();

         QDeclarativeListProperty<QGraphicsLayoutItem> children() { return QDeclarativeListProperty<QGraphicsLayoutItem>(this, 0, children_append, children_count, children_at, children_clear); }

         qreal contentsMargin() const;
         void setContentsMargin(qreal);

         void removeAt(int index);

         static LinearLayoutAttached *qmlAttachedProperties(QObject *);

     private slots:
         void updateStretch(QGraphicsLayoutItem*,int);
         void updateSpacing(QGraphicsLayoutItem*,int);
         void updateAlignment(QGraphicsLayoutItem*,Qt::Alignment);

     private:
         friend class LinearLayoutAttached;

         void clearChildren();
         void insertLayoutItem(int, QGraphicsLayoutItem *);

         static void children_append(QDeclarativeListProperty<QGraphicsLayoutItem> *prop, QGraphicsLayoutItem *item) {
             static_cast<GraphicsLinearLayoutObject*>(prop->object)->insertLayoutItem(-1, item);
         }

         static void children_clear(QDeclarativeListProperty<QGraphicsLayoutItem> *prop) {
             static_cast<GraphicsLinearLayoutObject*>(prop->object)->clearChildren();
         }

         static int children_count(QDeclarativeListProperty<QGraphicsLayoutItem> *prop) {
             return static_cast<GraphicsLinearLayoutObject*>(prop->object)->count();
         }

         static QGraphicsLayoutItem *children_at(QDeclarativeListProperty<QGraphicsLayoutItem> *prop, int index) {
             return static_cast<GraphicsLinearLayoutObject*>(prop->object)->itemAt(index);
         }

         static QHash<QGraphicsLayoutItem*, LinearLayoutAttached*> attachedProperties;
     };

     class LinearLayoutAttached : public QObject
     {
         Q_OBJECT

         Q_PROPERTY(int stretchFactor READ stretchFactor WRITE setStretchFactor NOTIFY stretchChanged)
         Q_PROPERTY(Qt::Alignment alignment READ alignment WRITE setAlignment NOTIFY alignmentChanged)
         Q_PROPERTY(int spacing READ spacing WRITE setSpacing NOTIFY spacingChanged)

     public:
         LinearLayoutAttached(QObject *parent);

         int stretchFactor() const { return m_stretch; }
         void setStretchFactor(int f);
         Qt::Alignment alignment() const { return m_alignment; }
         void setAlignment(Qt::Alignment a);
         int spacing() const { return m_spacing; }
         void setSpacing(int s);

     signals:
         void stretchChanged(QGraphicsLayoutItem*, int);
         void alignmentChanged(QGraphicsLayoutItem*, Qt::Alignment);
         void spacingChanged(QGraphicsLayoutItem*, int);

     private:
         int m_stretch;
         Qt::Alignment m_alignment;
         int m_spacing;
     };

     QML_DECLARE_INTERFACE(QGraphicsLayoutItem)
     QML_DECLARE_INTERFACE(QGraphicsLayout)
     QML_DECLARE_TYPE(GraphicsLinearLayoutStretchItemObject)
     QML_DECLARE_TYPE(GraphicsLinearLayoutObject)
     QML_DECLARE_TYPEINFO(GraphicsLinearLayoutObject, QML_HAS_ATTACHED_PROPERTIES)

     #endif