Merged very early alpha-version of Dolphin 2.0

Dolphin 2.0 will get a new view-engine with the
following improvements:
- Better performance
- Animated transitions
- No clipped filenames due to dynamic item-sizes
- Grouping support for all view-modes
- Non-rectangular selection areas
- Simplified code for better maintenance

More details will be provided in a blog-entry during
the next days.

Please note that the code is in a very
early alpha-stage and although the most tricky parts
have been implemented already very basic things like
drag and drop or selections have not been pushed yet.
Those things are rather trivial to implement but this
still will take some time.

1 files changed, 360 insertions, 0 deletions

diff --git a/src/kitemviews/kitemlistview.h b/src/kitemviews/kitemlistview.h
new file mode 100644
index 000000000..829736a09
--- /dev/null
+++ b/src/kitemviews/kitemlistview.h
@@ -0,0 +1,360 @@
+/***************************************************************************
+ *   Copyright (C) 2011 by Peter Penz <[email protected]>             *
+ *                                                                         *
+ *   Based on the Itemviews NG project from Trolltech Labs:                *
+ *   http://qt.gitorious.org/qt-labs/itemviews-ng                          *
+ *                                                                         *
+ *   This program 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.                                   *
+ *                                                                         *
+ *   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 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 KITEMLISTVIEW_H
+#define KITEMLISTVIEW_H
+
+#include <libdolphin_export.h>
+
+#include <kitemviews/kitemliststyleoption.h>
+#include <kitemviews/kitemlistviewanimation_p.h>
+#include <kitemviews/kitemlistwidget.h>
+#include <kitemviews/kitemmodelbase.h>
+#include <QGraphicsWidget>
+
+class KItemListController;
+class KItemListWidgetCreatorBase;
+class KItemListGroupHeader;
+class KItemListGroupHeaderCreatorBase;
+class KItemListSizeHintResolver;
+class KItemListViewAnimation;
+class KItemListViewLayouter;
+class KItemListWidget;
+class KItemListViewCreatorBase;
+class QTimer;
+
+/**
+ * @brief Represents the view of an item-list.
+ *
+ * The view is responsible for showing the items of the model within
+ * a GraphicsItem. Each visible item is represented by a KItemListWidget.
+ *
+ * The created view must be applied to the KItemListController with
+ * KItemListController::setView(). For showing a custom model it is not
+ * mandatory to derive from KItemListView, all that is necessary is
+ * to set a widget-creator that is capable to create KItemListWidgets
+ * showing the model items. A widget-creator can be set with
+ * KItemListView::setWidgetCreator().
+ *
+ * @see KItemListWidget
+ * @see KItemModelBase
+ */
+class LIBDOLPHINPRIVATE_EXPORT KItemListView : public QGraphicsWidget
+{
+    Q_OBJECT
+
+public:
+    KItemListView(QGraphicsWidget* parent = 0);
+    virtual ~KItemListView();
+
+    void setScrollOrientation(Qt::Orientation orientation);
+    Qt::Orientation scrollOrientation() const;
+
+    void setItemSize(const QSizeF& size);
+    QSizeF itemSize() const;
+
+    // TODO: add note that offset is not checked against maximumOffset, only against 0.
+    void setOffset(qreal offset);
+    qreal offset() const;
+
+    qreal maximumOffset() const;
+
+    /**
+     * Sets the visible roles to \p roles. The integer-value defines
+     * the order of the visible role: Smaller values are ordered first.
+     */
+    void setVisibleRoles(const QHash<QByteArray, int>& roles);
+    QHash<QByteArray, int> visibleRoles() const;
+
+    /**
+     * @return Controller of the item-list. The controller gets
+     *         initialized by KItemListController::setView() and will
+     *         result in calling KItemListController::onControllerChanged().
+     */
+    KItemListController* controller() const;
+
+    /**
+     * @return Model of the item-list. The model gets
+     *         initialized by KItemListController::setView() and will
+     *         result in calling KItemListController::onModelChanged().
+     */
+    KItemModelBase* model() const;
+
+    /**
+     * Sets the creator that creates a widget showing the
+     * content of one model-item. Usually it is sufficient
+     * to implement a custom widget X derived from KItemListWidget and
+     * set the creator by:
+     * <code>
+     * itemListView->setWidgetCreator(new KItemListWidgetCreator<X>());
+     * </code>
+     * Note that the ownership of the widget creator is not transferred to
+     * the item-list view: One instance of a widget creator might get shared
+     * by several item-list view instances.
+     **/
+    void setWidgetCreator(KItemListWidgetCreatorBase* widgetCreator);
+    KItemListWidgetCreatorBase* widgetCreator() const;
+
+    void setGroupHeaderCreator(KItemListGroupHeaderCreatorBase* groupHeaderCreator);
+    KItemListGroupHeaderCreatorBase* groupHeaderCreator() const;
+
+    void setStyleOption(const KItemListStyleOption& option);
+    const KItemListStyleOption& styleOption() const;
+
+    virtual void setGeometry(const QRectF& rect);
+
+    int itemAt(const QPointF& pos) const;
+    bool isAboveSelectionToggle(int index, const QPointF& pos) const;
+    bool isAboveExpansionToggle(int index, const QPointF& pos) const;
+
+    int firstVisibleIndex() const;
+    int lastVisibleIndex() const;
+
+    virtual QSizeF itemSizeHint(int index) const;
+    virtual QHash<QByteArray, QSizeF> visibleRoleSizes() const;
+
+    void beginTransaction();
+    void endTransaction();
+    bool isTransactionActive() const;
+
+signals:
+    void offsetChanged(int current, int previous);
+    void maximumOffsetChanged(int current, int previous);
+
+protected:
+    virtual void initializeItemListWidget(KItemListWidget* item);
+
+    virtual void onControllerChanged(KItemListController* current, KItemListController* previous);
+    virtual void onModelChanged(KItemModelBase* current, KItemModelBase* previous);
+
+    virtual void onScrollOrientationChanged(Qt::Orientation current, Qt::Orientation previous);
+    virtual void onItemSizeChanged(const QSizeF& current, const QSizeF& previous);
+    virtual void onOffsetChanged(qreal current, qreal previous);
+    virtual void onVisibleRolesChanged(const QHash<QByteArray, int>& current, const QHash<QByteArray, int>& previous);
+    virtual void onStyleOptionChanged(const KItemListStyleOption& current, const KItemListStyleOption& previous);
+
+    virtual void onTransactionBegin();
+    virtual void onTransactionEnd();
+
+    virtual bool event(QEvent* event);
+    virtual void mousePressEvent(QGraphicsSceneMouseEvent* event);
+    virtual void hoverMoveEvent(QGraphicsSceneHoverEvent* event);
+    virtual void hoverLeaveEvent(QGraphicsSceneHoverEvent* event);
+
+    QList<KItemListWidget*> visibleItemListWidgets() const;
+
+protected slots:
+    virtual void slotItemsInserted(const KItemRangeList& itemRanges);
+    virtual void slotItemsRemoved(const KItemRangeList& itemRanges);
+    virtual void slotItemsChanged(const KItemRangeList& itemRanges,
+                                  const QSet<QByteArray>& roles);
+
+private slots:
+    void slotAnimationFinished(QGraphicsWidget* widget,
+                               KItemListViewAnimation::AnimationType type);
+    void slotLayoutTimerFinished();
+
+private:
+    enum LayoutAnimationHint
+    {
+        NoAnimation,
+        Animation
+    };
+
+    enum SizeType
+    {
+        LayouterSize,
+        ItemSize
+    };
+
+    void setController(KItemListController* controller);
+    void setModel(KItemModelBase* model);
+
+    void updateLayout();
+    void doLayout(LayoutAnimationHint hint, int changedIndex, int changedCount);
+    void doGroupHeadersLayout(LayoutAnimationHint hint, int changedIndex, int changedCount);
+    void emitOffsetChanges();
+
+    KItemListWidget* createWidget(int index);
+    void recycleWidget(KItemListWidget* widget);
+    void setWidgetIndex(KItemListWidget* widget, int index);
+
+    /**
+     * Helper method for setGeometry() and setItemSize(): Calling both methods might result
+     * in a changed number of visible items. To assure that currently invisible items can
+     * get animated from the old position to the new position prepareLayoutForIncreasedItemCount()
+     * takes care to create all item widgets that are visible with the old or the new size.
+     * @param size     Size of the layouter or the item dependent on \p sizeType.
+     * @param sizeType LayouterSize: KItemListLayouter::setSize() is used.
+     *                 ItemSize: KItemListLayouter::setItemSize() is used.
+     */
+    void prepareLayoutForIncreasedItemCount(const QSizeF& size, SizeType sizeType);
+
+    /**
+     * Helper method for prepareLayoutForIncreasedItemCount().
+     */
+    void setLayouterSize(const QSizeF& size, SizeType sizeType);
+
+    /**
+     * Marks the visible roles as dirty so that they will get updated when doing the next
+     * layout. The visible roles will only get marked as dirty if an empty item-size is
+     * given.
+     * @return True if the visible roles have been marked as dirty.
+     */
+    bool markVisibleRolesSizesAsDirty();
+
+    /**
+     * Updates the m_visibleRoleSizes property and applies the dynamic
+     * size to the layouter.
+     */
+    void applyDynamicItemSize();
+
+private:
+    bool m_grouped;
+    int m_activeTransactions; // Counter for beginTransaction()/endTransaction()
+
+    QSizeF m_itemSize;
+    KItemListController* m_controller;
+    KItemModelBase* m_model;
+    QHash<QByteArray, int> m_visibleRoles;
+    QHash<QByteArray, QSizeF> m_visibleRolesSizes;
+    KItemListWidgetCreatorBase* m_widgetCreator;
+    KItemListGroupHeaderCreatorBase* m_groupHeaderCreator;
+    KItemListStyleOption m_styleOption;
+
+    QHash<int, KItemListWidget*> m_visibleItems;
+    QHash<KItemListWidget*, KItemListGroupHeader*> m_visibleGroups;
+
+    int m_scrollBarExtent;
+    KItemListSizeHintResolver* m_sizeHintResolver;
+    KItemListViewLayouter* m_layouter;
+    KItemListViewAnimation* m_animation;
+
+    QTimer* m_layoutTimer; // Triggers an asynchronous doLayout() call.
+    int m_oldOffset;
+    int m_oldMaximumOffset;
+
+    friend class KItemListController;
+};
+
+/**
+ * Allows to do a fast logical creation and deletion of QGraphicsWidgets
+ * by recycling existing QGraphicsWidgets instances. Is used by
+ * KItemListWidgetCreatorBase and KItemListGroupHeaderCreatorBase.
+ * @internal
+ */
+class LIBDOLPHINPRIVATE_EXPORT KItemListCreatorBase
+{
+public:
+    virtual ~KItemListCreatorBase();
+
+protected:
+    void addCreatedWidget(QGraphicsWidget* widget);
+    void pushRecycleableWidget(QGraphicsWidget* widget);
+    QGraphicsWidget* popRecycleableWidget();
+
+private:
+    QSet<QGraphicsWidget*> m_createdWidgets;
+    QList<QGraphicsWidget*> m_recycleableWidgets;
+};
+
+/**
+ * @brief Base class for creating KItemListWidgets.
+ *
+ * It is recommended that applications simply use the KItemListWidgetCreator-template class.
+ * For a custom implementation the methods create() and recyle() must be reimplemented.
+ * The intention of the widget creator is to prevent repetitive and expensive instantiations and
+ * deletions of KItemListWidgets by recycling existing widget instances.
+ */
+class LIBDOLPHINPRIVATE_EXPORT KItemListWidgetCreatorBase : public KItemListCreatorBase
+{
+public:
+    virtual ~KItemListWidgetCreatorBase();
+    virtual KItemListWidget* create(KItemListView* view) = 0;
+    virtual void recycle(KItemListWidget* widget);
+};
+
+template <class T>
+class LIBDOLPHINPRIVATE_EXPORT KItemListWidgetCreator : public KItemListWidgetCreatorBase
+{
+public:
+    virtual ~KItemListWidgetCreator();
+    virtual KItemListWidget* create(KItemListView* view);
+};
+
+template <class T>
+KItemListWidgetCreator<T>::~KItemListWidgetCreator()
+{
+}
+
+template <class T>
+KItemListWidget* KItemListWidgetCreator<T>::create(KItemListView* view)
+{
+    KItemListWidget* widget = static_cast<KItemListWidget*>(popRecycleableWidget());
+    if (!widget) {
+        widget = new T(view);
+        addCreatedWidget(widget);
+    }
+    return widget;
+}
+
+/**
+ * @brief Base class for creating KItemListGroupHeaders.
+ *
+ * It is recommended that applications simply use the KItemListGroupHeaderCreator-template class.
+ * For a custom implementation the methods create() and recyle() must be reimplemented.
+ * The intention of the group-header creator is to prevent repetitive and expensive instantiations and
+ * deletions of KItemListGroupHeaders by recycling existing header instances.
+ */
+class LIBDOLPHINPRIVATE_EXPORT KItemListGroupHeaderCreatorBase : public KItemListCreatorBase
+{
+public:
+    virtual ~KItemListGroupHeaderCreatorBase();
+    virtual KItemListGroupHeader* create(QGraphicsWidget* parent) = 0;
+    virtual void recycle(KItemListGroupHeader* header);
+};
+
+template <class T>
+class LIBDOLPHINPRIVATE_EXPORT KItemListGroupHeaderCreator : public KItemListGroupHeaderCreatorBase
+{
+public:
+    virtual ~KItemListGroupHeaderCreator();
+    virtual KItemListGroupHeader* create(QGraphicsWidget* parent);
+};
+
+template <class T>
+KItemListGroupHeaderCreator<T>::~KItemListGroupHeaderCreator()
+{
+}
+
+template <class T>
+KItemListGroupHeader* KItemListGroupHeaderCreator<T>::create(QGraphicsWidget* parent)
+{
+    KItemListGroupHeader* widget = static_cast<KItemListGroupHeader*>(popRecycleableWidget());
+    if (!widget) {
+        widget = new T(parent);
+        addCreatedWidget(widget);
+    }
+    return widget;
+}
+
+#endif