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<QSizeF>& sizeHints, 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 setAlternateBackground(bool enable);
 112     bool alternateBackground() const;
 113
 114     void setEnabledSelectionToggle(bool enabled);
 115     bool enabledSelectionToggle() const;
 116
 117     /**
 118      * Sets the sibling information for the item and all of its parents.
 119      * The sibling information of the upper most parent is represented by
 120      * the first bit, the sibling information of the item by the last bit.
 121      * The sibling information is useful for drawing the branches in
 122      * tree views.
 123      */
 124     void setSiblingsInformation(const QBitArray& siblings);
 125     QBitArray siblingsInformation() const;
 126
 127     /**
 128      * Allows the user to edit the role \a role. The signals
 129      * roleEditingCanceled() or roleEditingFinished() will be
 130      * emitted after editing. An ongoing editing gets canceled if
 131      * the role is empty. Derived classes must implement
 132      * editedRoleChanged().
 133      */
 134     void setEditedRole(const QByteArray& role);
 135     QByteArray editedRole() const;
 136
 137     /**
 138      * @return True if \a point is inside KItemListWidget::hoverRect(),
 139      *         KItemListWidget::textRect(), KItemListWidget::selectionToggleRect()
 140      *         or KItemListWidget::expansionToggleRect().
 141      * @reimp
 142      */
 143     virtual bool contains(const QPointF& point) const;
 144
 145     /**
 146      * @return Rectangle for the area that shows the icon.
 147      */
 148     virtual QRectF iconRect() const = 0;
 149
 150     /**
 151      * @return Rectangle for the area that contains the text-properties.
 152      */
 153     virtual QRectF textRect() const = 0;
 154
 155     /**
 156      * @return Focus rectangle for indicating the current item. Per default
 157      *         textRect() will be returned. Overwrite this method if textRect()
 158      *         provides a larger rectangle than the actual text (e.g. to
 159      *         be aligned with the iconRect()). The textFocusRect() may not be
 160      *         outside the boundaries of textRect().
 161      */
 162     virtual QRectF textFocusRect() const;
 163
 164     /**
 165      * @return Rectangle for the selection-toggle that is used to select or deselect an item.
 166      *         Per default an empty rectangle is returned which means that no selection-toggle
 167      *         is available.
 168      */
 169     virtual QRectF selectionToggleRect() const;
 170
 171     /**
 172      * @return Rectangle for the expansion-toggle that is used to open a sub-tree of the model.
 173      *         Per default an empty rectangle is returned which means that no opening of sub-trees
 174      *         is supported.
 175      */
 176     virtual QRectF expansionToggleRect() const;
 177
 178     /**
 179      * @return Pixmap that is used when dragging an item. Per default the current state of the
 180      *         widget is returned as pixmap.
 181      */
 182     virtual QPixmap createDragPixmap(const QStyleOptionGraphicsItem* option, QWidget* widget = 0);
 183
 184 signals:
 185     void roleEditingCanceled(int index, const QByteArray& role, const QVariant& value);
 186     void roleEditingFinished(int index, const QByteArray& role, const QVariant& value);
 187
 188 protected:
 189     virtual void dataChanged(const QHash<QByteArray, QVariant>& current, const QSet<QByteArray>& roles = QSet<QByteArray>());
 190     virtual void visibleRolesChanged(const QList<QByteArray>& current, const QList<QByteArray>& previous);
 191     virtual void columnWidthChanged(const QByteArray& role, qreal current, qreal previous);
 192     virtual void styleOptionChanged(const KItemListStyleOption& current, const KItemListStyleOption& previous);
 193     virtual void currentChanged(bool current);
 194     virtual void selectedChanged(bool selected);
 195     virtual void hoveredChanged(bool hovered);
 196     virtual void alternateBackgroundChanged(bool enabled);
 197     virtual void siblingsInformationChanged(const QBitArray& current, const QBitArray& previous);
 198     virtual void editedRoleChanged(const QByteArray& current, const QByteArray& previous);
 199     virtual void resizeEvent(QGraphicsSceneResizeEvent* event);
 200
 201     /**
 202      * @return The current opacity of the hover-animation. When implementing a custom painting-code for a hover-state
 203      *         this opacity value should be respected.
 204      */
 205     qreal hoverOpacity() const;
 206
 207     const KItemListWidgetInformant* informant() const;
 208
 209 private slots:
 210     void slotHoverAnimationFinished();
 211
 212 private:
 213     void initializeSelectionToggle();
 214     void setHoverOpacity(qreal opacity);
 215     void clearHoverCache();
 216     void drawItemStyleOption(QPainter* painter, QWidget* widget, QStyle::State styleState);
 217
 218 private:
 219     Q_PROPERTY(qreal hoverOpacity READ hoverOpacity WRITE setHoverOpacity)
 220
 221     KItemListWidgetInformant* m_informant;
 222     int m_index;
 223     bool m_selected;
 224     bool m_current;
 225     bool m_hovered;
 226     bool m_alternateBackground;
 227     bool m_enabledSelectionToggle;
 228     QHash<QByteArray, QVariant> m_data;
 229     QList<QByteArray> m_visibleRoles;
 230     QHash<QByteArray, qreal> m_columnWidths;
 231     KItemListStyleOption m_styleOption;
 232     QBitArray m_siblingsInfo;
 233
 234     qreal m_hoverOpacity;
 235     mutable QPixmap* m_hoverCache;
 236     QPropertyAnimation* m_hoverAnimation;
 237
 238     KItemListSelectionToggle* m_selectionToggle;
 239
 240     QByteArray m_editedRole;
 241 };
 242
 243 inline const KItemListWidgetInformant* KItemListWidget::informant() const
 244 {
 245     return m_informant;
 246 }
 247
 248 #endif
 249
 250