src/kitemviews/kitemlistwidget.h

   1 /***************************************************************************
   2  *   Copyright (C) 2011 by Peter Penz <peter.penz19@gmail.com>             *
   3  *                                                                         *
   4  *   Based on the Itemviews NG project from Trolltech Labs:                *
   5  *   http://qt.gitorious.org/qt-labs/itemviews-ng                          *
   6  *                                                                         *
   7  *   This program is free software; you can redistribute it and/or modify  *
   8  *   it under the terms of the GNU General Public License as published by  *
   9  *   the Free Software Foundation; either version 2 of the License, or     *
  10  *   (at your option) any later version.                                   *
  11  *                                                                         *
  12  *   This program is distributed in the hope that it will be useful,       *
  13  *   but WITHOUT ANY WARRANTY; without even the implied warranty of        *
  14  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the         *
  15  *   GNU General Public License for more details.                          *
  16  *                                                                         *
  17  *   You should have received a copy of the GNU General Public License     *
  18  *   along with this program; if not, write to the                         *
  19  *   Free Software Foundation, Inc.,                                       *
  20  *   51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA            *
  21  ***************************************************************************/
  22
  23 #ifndef KITEMLISTWIDGET_H
  24 #define KITEMLISTWIDGET_H
  25
  26 #include <libdolphin_export.h>
  27
  28 #include <kitemviews/kitemliststyleoption.h>
  29
  30 #include <QBitArray>
  31 #include <QGraphicsWidget>
  32 #include <QStyle>
  33
  34 class KItemListSelectionToggle;
  35 class KItemListView;
  36 class QPropertyAnimation;
  37
  38 /**
  39  * @brief Provides information for creating an instance of KItemListWidget.
  40  *
  41  * KItemListView only creates KItemListWidget instances for the visible
  42  * area. For calculating the required size of all items the expected
  43  * size for the invisible items must be accessible. KItemListWidgetInformant
  44  * provides this information.
  45  */
  46 class LIBDOLPHINPRIVATE_EXPORT KItemListWidgetInformant
  47 {
  48 public:
  49     KItemListWidgetInformant();
  50     virtual ~KItemListWidgetInformant();
  51
  52     virtual void calculateItemSizeHints(QVector<qreal>& logicalHeightHints, qreal& logicalWidthHint, const KItemListView* view) const = 0;
  53
  54     virtual qreal preferredRoleColumnWidth(const QByteArray& role,
  55                                            int index,
  56                                            const KItemListView* view) const = 0;
  57 };
  58
  59 /**
  60  * @brief Widget that shows a visible item from the model.
  61  *
  62  * For showing an item from a custom model it is required to at least overwrite KItemListWidget::paint().
  63  * All properties are set by KItemListView, for each property there is a corresponding
  64  * virtual protected method that allows to react on property changes.
  65  */
  66 class LIBDOLPHINPRIVATE_EXPORT KItemListWidget : public QGraphicsWidget
  67 {
  68     Q_OBJECT
  69
  70 public:
  71     KItemListWidget(KItemListWidgetInformant* informant, QGraphicsItem* parent);
  72     virtual ~KItemListWidget();
  73
  74     void setIndex(int index);
  75     int index() const;
  76
  77     void setData(const QHash<QByteArray, QVariant>& data, const QSet<QByteArray>& roles = QSet<QByteArray>());
  78     QHash<QByteArray, QVariant> data() const;
  79
  80     /**
  81      * Draws the hover-rectangle if the item is hovered. Overwrite this method
  82      * to show the data of the custom model provided by KItemListWidget::data().
  83      * @reimp
  84      */
  85     virtual void paint(QPainter* painter, const QStyleOptionGraphicsItem* option, QWidget* widget = 0);
  86
  87     void setVisibleRoles(const QList<QByteArray>& roles);
  88     QList<QByteArray> visibleRoles() const;
  89
  90     /**
  91      * Sets the width of a role that should be used if the alignment of the content
  92      * should be done in columns.
  93      */
  94     void setColumnWidth(const QByteArray& role, qreal width);
  95     qreal columnWidth(const QByteArray& role) const;
  96
  97     void setStyleOption(const KItemListStyleOption& option);
  98     const KItemListStyleOption& styleOption() const;
  99
 100     // TODO: Hides QGraphicsItem::setSelected()/isSelected(). Replace
 101     // this by using the default mechanism.
 102     void setSelected(bool selected);
 103     bool isSelected() const;
 104
 105     void setCurrent(bool current);
 106     bool isCurrent() const;
 107
 108     void setHovered(bool hovered);
 109     bool isHovered() const;
 110
 111     void setHoverPosition(const QPointF& pos);
 112
 113     void setAlternateBackground(bool enable);
 114     bool alternateBackground() const;
 115
 116     void setEnabledSelectionToggle(bool enabled);
 117     bool enabledSelectionToggle() const;
 118
 119     /**
 120      * Sets the sibling information for the item and all of its parents.
 121      * The sibling information of the upper most parent is represented by
 122      * the first bit, the sibling information of the item by the last bit.
 123      * The sibling information is useful for drawing the branches in
 124      * tree views.
 125      */
 126     void setSiblingsInformation(const QBitArray& siblings);
 127     QBitArray siblingsInformation() const;
 128
 129     /**
 130      * Allows the user to edit the role \a role. The signals
 131      * roleEditingCanceled() or roleEditingFinished() will be
 132      * emitted after editing. An ongoing editing gets canceled if
 133      * the role is empty. Derived classes must implement
 134      * editedRoleChanged().
 135      */
 136     void setEditedRole(const QByteArray& role);
 137     QByteArray editedRole() const;
 138
 139     /**
 140      * @return True if \a point is inside KItemListWidget::hoverRect(),
 141      *         KItemListWidget::textRect(), KItemListWidget::selectionToggleRect()
 142      *         or KItemListWidget::expansionToggleRect().
 143      * @reimp
 144      */
 145     virtual bool contains(const QPointF& point) const;
 146
 147     /**
 148      * @return Rectangle for the area that shows the icon.
 149      */
 150     virtual QRectF iconRect() const = 0;
 151
 152     /**
 153      * @return Rectangle for the area that contains the text-properties.
 154      */
 155     virtual QRectF textRect() const = 0;
 156
 157     /**
 158      * @return Focus rectangle for indicating the current item. Per default
 159      *         textRect() will be returned. Overwrite this method if textRect()
 160      *         provides a larger rectangle than the actual text (e.g. to
 161      *         be aligned with the iconRect()). The textFocusRect() may not be
 162      *         outside the boundaries of textRect().
 163      */
 164     virtual QRectF textFocusRect() const;
 165
 166     /**
 167      * @return Rectangle around which a selection box should be drawn if the item is selected.
 168      */
 169     virtual QRectF selectionRect() const = 0;
 170
 171     /**
 172      * @return Rectangle for the selection-toggle that is used to select or deselect an item.
 173      *         Per default an empty rectangle is returned which means that no selection-toggle
 174      *         is available.
 175      */
 176     virtual QRectF selectionToggleRect() const;
 177
 178     /**
 179      * @return Rectangle for the expansion-toggle that is used to open a sub-tree of the model.
 180      *         Per default an empty rectangle is returned which means that no opening of sub-trees
 181      *         is supported.
 182      */
 183     virtual QRectF expansionToggleRect() const;
 184
 185     /**
 186      * @return Pixmap that is used when dragging an item. Per default the current state of the
 187      *         widget is returned as pixmap.
 188      */
 189     virtual QPixmap createDragPixmap(const QStyleOptionGraphicsItem* option, QWidget* widget = 0);
 190
 191 signals:
 192     void roleEditingCanceled(int index, const QByteArray& role, const QVariant& value);
 193     void roleEditingFinished(int index, const QByteArray& role, const QVariant& value);
 194
 195 protected:
 196     virtual void dataChanged(const QHash<QByteArray, QVariant>& current, const QSet<QByteArray>& roles = QSet<QByteArray>());
 197     virtual void visibleRolesChanged(const QList<QByteArray>& current, const QList<QByteArray>& previous);
 198     virtual void columnWidthChanged(const QByteArray& role, qreal current, qreal previous);
 199     virtual void styleOptionChanged(const KItemListStyleOption& current, const KItemListStyleOption& previous);
 200     virtual void currentChanged(bool current);
 201     virtual void selectedChanged(bool selected);
 202     virtual void hoveredChanged(bool hovered);
 203     virtual void alternateBackgroundChanged(bool enabled);
 204     virtual void siblingsInformationChanged(const QBitArray& current, const QBitArray& previous);
 205     virtual void editedRoleChanged(const QByteArray& current, const QByteArray& previous);
 206     virtual void resizeEvent(QGraphicsSceneResizeEvent* event);
 207
 208     /**
 209      * @return The current opacity of the hover-animation. When implementing a custom painting-code for a hover-state
 210      *         this opacity value should be respected.
 211      */
 212     qreal hoverOpacity() const;
 213
 214     const KItemListWidgetInformant* informant() const;
 215
 216 private slots:
 217     void slotHoverAnimationFinished();
 218
 219 private:
 220     void initializeSelectionToggle();
 221     void setHoverOpacity(qreal opacity);
 222     void clearHoverCache();
 223     void drawItemStyleOption(QPainter* painter, QWidget* widget, QStyle::State styleState);
 224
 225 private:
 226     Q_PROPERTY(qreal hoverOpacity READ hoverOpacity WRITE setHoverOpacity)
 227
 228     KItemListWidgetInformant* m_informant;
 229     int m_index;
 230     bool m_selected;
 231     bool m_current;
 232     bool m_hovered;
 233     bool m_alternateBackground;
 234     bool m_enabledSelectionToggle;
 235     QHash<QByteArray, QVariant> m_data;
 236     QList<QByteArray> m_visibleRoles;
 237     QHash<QByteArray, qreal> m_columnWidths;
 238     KItemListStyleOption m_styleOption;
 239     QBitArray m_siblingsInfo;
 240
 241     qreal m_hoverOpacity;
 242     mutable QPixmap* m_hoverCache;
 243     QPropertyAnimation* m_hoverAnimation;
 244
 245     KItemListSelectionToggle* m_selectionToggle;
 246
 247     QByteArray m_editedRole;
 248 };
 249
 250 inline const KItemListWidgetInformant* KItemListWidget::informant() const
 251 {
 252     return m_informant;
 253 }
 254
 255 #endif
 256
 257