src/kitemviews/kitemlistwidget.h

   1 /*
   2  * SPDX-FileCopyrightText: 2011 Peter Penz <peter.penz19@gmail.com>
   3  *
   4  * Based on the Itemviews NG project from Trolltech Labs
   5  *
   6  * SPDX-License-Identifier: GPL-2.0-or-later
   7  */
   8
   9 #ifndef KITEMLISTWIDGET_H
  10 #define KITEMLISTWIDGET_H
  11
  12 #include "dolphin_export.h"
  13 #include "kitemviews/kitemliststyleoption.h"
  14
  15 #include <QBitArray>
  16 #include <QGraphicsWidget>
  17 #include <QStyle>
  18 #include <QTimer>
  19
  20 class KItemListSelectionToggle;
  21 class KItemListView;
  22 class QPropertyAnimation;
  23
  24 /**
  25  * @brief Provides information for creating an instance of KItemListWidget.
  26  *
  27  * KItemListView only creates KItemListWidget instances for the visible
  28  * area. For calculating the required size of all items the expected
  29  * size for the invisible items must be accessible. KItemListWidgetInformant
  30  * provides this information.
  31  */
  32 class DOLPHIN_EXPORT KItemListWidgetInformant
  33 {
  34 public:
  35     KItemListWidgetInformant();
  36     virtual ~KItemListWidgetInformant();
  37
  38     virtual void calculateItemSizeHints(QVector<std::pair<qreal, bool>> &logicalHeightHints, qreal &logicalWidthHint, const KItemListView *view) const = 0;
  39
  40     virtual qreal preferredRoleColumnWidth(const QByteArray &role, int index, const KItemListView *view) const = 0;
  41 };
  42
  43 /**
  44  * @brief Widget that shows a visible item from the model.
  45  *
  46  * For showing an item from a custom model it is required to at least overwrite KItemListWidget::paint().
  47  * All properties are set by KItemListView, for each property there is a corresponding
  48  * virtual protected method that allows to react on property changes.
  49  */
  50 class DOLPHIN_EXPORT KItemListWidget : public QGraphicsWidget
  51 {
  52     Q_OBJECT
  53
  54     Q_PROPERTY(int iconSize READ iconSize WRITE setIconSize)
  55
  56 public:
  57     KItemListWidget(KItemListWidgetInformant *informant, QGraphicsItem *parent);
  58     ~KItemListWidget() override;
  59
  60     void setIndex(int index);
  61     int index() const;
  62
  63     void setData(const QHash<QByteArray, QVariant> &data, const QSet<QByteArray> &roles = QSet<QByteArray>());
  64     QHash<QByteArray, QVariant> data() const;
  65
  66     /**
  67      * Draws the hover-rectangle if the item is hovered. Overwrite this method
  68      * to show the data of the custom model provided by KItemListWidget::data().
  69      * @reimp
  70      */
  71     void paint(QPainter *painter, const QStyleOptionGraphicsItem *option, QWidget *widget = nullptr) override;
  72
  73     void setVisibleRoles(const QList<QByteArray> &roles);
  74     QList<QByteArray> visibleRoles() const;
  75
  76     /**
  77      * Sets the width of a role that should be used if the alignment of the content
  78      * should be done in columns.
  79      */
  80     void setColumnWidth(const QByteArray &role, qreal width);
  81     qreal columnWidth(const QByteArray &role) const;
  82
  83     void setSidePadding(qreal width);
  84     qreal sidePadding() const;
  85
  86     void setStyleOption(const KItemListStyleOption &option);
  87     const KItemListStyleOption &styleOption() const;
  88
  89     // TODO: Hides QGraphicsItem::setSelected()/isSelected(). Replace
  90     // this by using the default mechanism.
  91     void setSelected(bool selected);
  92     bool isSelected() const;
  93
  94     void setCurrent(bool current);
  95     bool isCurrent() const;
  96
  97     void setHovered(bool hovered);
  98     bool isHovered() const;
  99
 100     void setExpansionAreaHovered(bool hover);
 101     bool expansionAreaHovered() const;
 102
 103     void setHoverPosition(const QPointF &pos);
 104
 105     void setAlternateBackground(bool enable);
 106     bool alternateBackground() const;
 107
 108     void setEnabledSelectionToggle(bool enabled);
 109     bool enabledSelectionToggle() const;
 110
 111     /**
 112      * Sets the sibling information for the item and all of its parents.
 113      * The sibling information of the upper most parent is represented by
 114      * the first bit, the sibling information of the item by the last bit.
 115      * The sibling information is useful for drawing the branches in
 116      * tree views.
 117      */
 118     void setSiblingsInformation(const QBitArray &siblings);
 119     QBitArray siblingsInformation() const;
 120
 121     /**
 122      * Allows the user to edit the role \a role. The signals
 123      * roleEditingCanceled() or roleEditingFinished() will be
 124      * emitted after editing. An ongoing editing gets canceled if
 125      * the role is empty. Derived classes must implement
 126      * editedRoleChanged().
 127      */
 128     void setEditedRole(const QByteArray &role);
 129     QByteArray editedRole() const;
 130
 131     /**
 132      * Contains the actual icon size used to draw the icon.
 133      * Also used during icon resizing animation.
 134      */
 135     void setIconSize(int iconSize);
 136     int iconSize() const;
 137
 138     /**
 139      * @return True if \a point is inside KItemListWidget::hoverRect(),
 140      *         KItemListWidget::textRect(), KItemListWidget::selectionToggleRect()
 141      *         or KItemListWidget::expansionToggleRect().
 142      * @reimp
 143      */
 144     bool contains(const QPointF &point) const override;
 145
 146     /**
 147      * @return Rectangle for the area that shows the icon.
 148      */
 149     virtual QRectF iconRect() const = 0;
 150
 151     /**
 152      * @return Rectangle for the area that contains the text-properties.
 153      */
 154     virtual QRectF textRect() const = 0;
 155
 156     /**
 157      * @return Focus rectangle for indicating the current item. Per default
 158      *         textRect() will be returned. Overwrite this method if textRect()
 159      *         provides a larger rectangle than the actual text (e.g. to
 160      *         be aligned with the iconRect()). The textFocusRect() may not be
 161      *         outside the boundaries of textRect().
 162      */
 163     virtual QRectF textFocusRect() const;
 164
 165     /**
 166      * @return Rectangle around which a selection box should be drawn if the item is selected.
 167      */
 168     virtual QRectF selectionRect() const = 0;
 169
 170     /**
 171      * @return Rectangle for the selection-toggle that is used to select or deselect an item.
 172      *         Per default an empty rectangle is returned which means that no selection-toggle
 173      *         is available.
 174      */
 175     virtual QRectF selectionToggleRect() const;
 176
 177     /**
 178      * @return Rectangle for the expansion-toggle that is used to open a sub-tree of the model.
 179      *         Per default an empty rectangle is returned which means that no opening of sub-trees
 180      *         is supported.
 181      */
 182     virtual QRectF expansionToggleRect() const;
 183
 184     /**
 185      * @return Pixmap that is used when dragging an item. Per default the current state of the
 186      *         widget is returned as pixmap.
 187      */
 188     virtual QPixmap createDragPixmap(const QStyleOptionGraphicsItem *option, QWidget *widget = nullptr);
 189
 190 Q_SIGNALS:
 191     void roleEditingCanceled(int index, const QByteArray &role, const QVariant &value);
 192     void roleEditingFinished(int index, const QByteArray &role, const QVariant &value);
 193
 194 protected:
 195     virtual void dataChanged(const QHash<QByteArray, QVariant> &current, const QSet<QByteArray> &roles = QSet<QByteArray>());
 196     virtual void visibleRolesChanged(const QList<QByteArray> &current, const QList<QByteArray> &previous);
 197     virtual void columnWidthChanged(const QByteArray &role, qreal current, qreal previous);
 198     virtual void sidePaddingChanged(qreal width);
 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 iconSizeChanged(int current, int previous);
 207     void resizeEvent(QGraphicsSceneResizeEvent *event) override;
 208     void clearHoverCache();
 209
 210     /**
 211      * Called when the user starts hovering this item.
 212      */
 213     virtual void hoverSequenceStarted();
 214
 215     /**
 216      * Called in regular intervals while the user is hovering this item.
 217      *
 218      * @param sequenceIndex An index that increases over time while the user hovers.
 219      */
 220     virtual void hoverSequenceIndexChanged(int sequenceIndex);
 221
 222     /**
 223      * Called when the user stops hovering this item.
 224      */
 225     virtual void hoverSequenceEnded();
 226
 227     /**
 228      * @return The current opacity of the hover-animation. When implementing a custom painting-code for a hover-state
 229      *         this opacity value should be respected.
 230      */
 231     qreal hoverOpacity() const;
 232
 233     int hoverSequenceIndex() const;
 234
 235     const KItemListWidgetInformant *informant() const;
 236
 237 private Q_SLOTS:
 238     void slotHoverAnimationFinished();
 239     void slotHoverSequenceTimerTimeout();
 240
 241 private:
 242     void initializeSelectionToggle();
 243     void setHoverOpacity(qreal opacity);
 244     void drawItemStyleOption(QPainter *painter, QWidget *widget, QStyle::State styleState);
 245
 246 private:
 247     Q_PROPERTY(qreal hoverOpacity READ hoverOpacity WRITE setHoverOpacity)
 248
 249     KItemListWidgetInformant *m_informant;
 250     int m_index;
 251     bool m_selected;
 252     bool m_current;
 253     bool m_hovered;
 254     bool m_expansionAreaHovered;
 255     bool m_alternateBackground;
 256     bool m_enabledSelectionToggle;
 257     QHash<QByteArray, QVariant> m_data;
 258     QList<QByteArray> m_visibleRoles;
 259     QHash<QByteArray, qreal> m_columnWidths;
 260     qreal m_sidePadding;
 261     KItemListStyleOption m_styleOption;
 262     QBitArray m_siblingsInfo;
 263
 264     qreal m_hoverOpacity;
 265     mutable QPixmap *m_hoverCache;
 266     QPropertyAnimation *m_hoverAnimation;
 267
 268     int m_hoverSequenceIndex;
 269     QTimer m_hoverSequenceTimer;
 270
 271     KItemListSelectionToggle *m_selectionToggle;
 272
 273     QByteArray m_editedRole;
 274     int m_iconSize;
 275 };
 276
 277 inline const KItemListWidgetInformant *KItemListWidget::informant() const
 278 {
 279     return m_informant;
 280 }
 281
 282 #endif