src/kitemviews/private/kitemlistheaderwidget.h

   1 /*
   2  * SPDX-FileCopyrightText: 2011 Peter Penz <peter.penz19@gmail.com>
   3  * SPDX-FileCopyrightText: 2022, 2024 Felix Ernst <felixernst@kde.org>
   4  *
   5  * SPDX-License-Identifier: GPL-2.0-or-later
   6  */
   7
   8 #ifndef KITEMLISTHEADERWIDGET_H
   9 #define KITEMLISTHEADERWIDGET_H
  10
  11 #include "dolphin_export.h"
  12
  13 #include <QGraphicsWidget>
  14 #include <QHash>
  15 #include <QList>
  16
  17 class KItemModelBase;
  18
  19 /**
  20  * @brief Widget the implements the header for KItemListView showing the currently used roles.
  21  *
  22  * The widget is an internal API, the user of KItemListView may only access the
  23  * class KItemListHeader.
  24  */
  25 class DOLPHIN_EXPORT KItemListHeaderWidget : public QGraphicsWidget
  26 {
  27     Q_OBJECT
  28
  29 public:
  30     explicit KItemListHeaderWidget(QGraphicsWidget *parent = nullptr);
  31     ~KItemListHeaderWidget() override;
  32
  33     void setModel(KItemModelBase *model);
  34     KItemModelBase *model() const;
  35
  36     void setAutomaticColumnResizing(bool automatic);
  37     bool automaticColumnResizing() const;
  38
  39     void setColumns(const QList<QByteArray> &roles);
  40     QList<QByteArray> columns() const;
  41
  42     void setColumnWidth(const QByteArray &role, qreal width);
  43     qreal columnWidth(const QByteArray &role) const;
  44
  45     /**
  46      * Sets the column-width that is required to show the role unclipped.
  47      */
  48     void setPreferredColumnWidth(const QByteArray &role, qreal width);
  49     qreal preferredColumnWidth(const QByteArray &role) const;
  50
  51     void setOffset(qreal offset);
  52     qreal offset() const;
  53
  54     void setSidePadding(qreal leftPaddingWidth, qreal rightPaddingWidth);
  55     qreal leftPadding() const;
  56     qreal rightPadding() const;
  57
  58     qreal minimumColumnWidth() const;
  59
  60     void paint(QPainter *painter, const QStyleOptionGraphicsItem *option, QWidget *widget = nullptr) override;
  61
  62 Q_SIGNALS:
  63     /**
  64      * Is emitted if the width of a visible role has been adjusted by the user with the mouse
  65      * (no signal is emitted if KItemListHeader::setVisibleRoleWidth() is invoked).
  66      */
  67     void columnWidthChanged(const QByteArray &role, qreal currentWidth, qreal previousWidth);
  68
  69     void sidePaddingChanged(qreal leftPaddingWidth, qreal rightPaddingWidth);
  70
  71     /**
  72      * Is emitted if the user has released the mouse button after adjusting the
  73      * width of a visible role.
  74      */
  75     void columnWidthChangeFinished(const QByteArray &role, qreal currentWidth);
  76
  77     /**
  78      * Is emitted if the position of the column has been changed.
  79      */
  80     void columnMoved(const QByteArray &role, int currentIndex, int previousIndex);
  81
  82     /**
  83      * Is emitted if the user has changed the sort order by clicking on a
  84      * header item. The sort order of the model has already been adjusted to
  85      * the current sort order. Note that no signal will be emitted if the
  86      * sort order of the model has been changed without user interaction.
  87      */
  88     void sortOrderChanged(Qt::SortOrder current, Qt::SortOrder previous);
  89
  90     /**
  91      * Is emitted if the user has changed the sort role by clicking on a
  92      * header item. The sort role of the model has already been adjusted to
  93      * the current sort role. Note that no signal will be emitted if the
  94      * sort role of the model has been changed without user interaction.
  95      */
  96     void sortRoleChanged(const QByteArray &current, const QByteArray &previous);
  97
  98     void columnUnHovered(int columnIndex);
  99     void columnHovered(int columnIndex);
 100
 101 protected:
 102     void mousePressEvent(QGraphicsSceneMouseEvent *event) override;
 103     void mouseReleaseEvent(QGraphicsSceneMouseEvent *event) override;
 104     void mouseMoveEvent(QGraphicsSceneMouseEvent *event) override;
 105     void mouseDoubleClickEvent(QGraphicsSceneMouseEvent *event) override;
 106     void hoverEnterEvent(QGraphicsSceneHoverEvent *event) override;
 107     void hoverLeaveEvent(QGraphicsSceneHoverEvent *event) override;
 108     void hoverMoveEvent(QGraphicsSceneHoverEvent *event) override;
 109
 110 private Q_SLOTS:
 111     void slotSortRoleChanged(const QByteArray &current, const QByteArray &previous);
 112     void slotSortOrderChanged(Qt::SortOrder current, Qt::SortOrder previous);
 113
 114 private:
 115     struct Grip {
 116         QByteArray roleToTheLeft;
 117         QByteArray roleToTheRight;
 118     };
 119
 120     void paintRole(QPainter *painter, const QByteArray &role, const QRectF &rect, int orderIndex, QWidget *widget = nullptr) const;
 121
 122     void updatePressedRoleIndex(const QPointF &pos);
 123     void updateHoveredIndex(const QPointF &pos);
 124     int roleIndexAt(const QPointF &pos) const;
 125
 126     /**
 127      * @returns std::nullopt if none of the resize grips is below @p position.
 128      *          Otherwise returns a Grip defined by the two roles on each side of @p position.
 129      * @note If the Grip is between a padding and a role, a class-specific "leftPadding" or "rightPadding" role is used.
 130      */
 131     std::optional<const Grip> isAboveResizeGrip(const QPointF &position) const;
 132
 133     /**
 134      * Creates a pixmap of the role with the index \a roleIndex that is shown
 135      * during moving a role.
 136      */
 137     QPixmap createRolePixmap(int roleIndex) const;
 138
 139     /**
 140      * @return Target index of the currently moving visible role based on the current
 141      *         state of m_movingRole.
 142      */
 143     int targetOfMovingRole() const;
 144
 145     /**
 146      * @return x-position of the left border of the role \a role.
 147      */
 148     qreal roleXPosition(const QByteArray &role) const;
 149
 150     /**
 151      * @returns 0 for left-to-right layoutDirection().
 152      *          Otherwise returns the space that is left over when space is distributed between padding and role columns.
 153      * Used to make the column headers stay above their information columns for right-to-left layout directions.
 154      */
 155     qreal unusedSpace() const;
 156
 157 private:
 158     bool m_automaticColumnResizing;
 159     KItemModelBase *m_model;
 160     qreal m_offset;
 161     qreal m_leftPadding;
 162     qreal m_rightPadding;
 163     QList<QByteArray> m_columns;
 164     QHash<QByteArray, qreal> m_columnWidths;
 165     QHash<QByteArray, qreal> m_preferredColumnWidths;
 166
 167     int m_hoveredIndex;
 168     std::optional<Grip> m_pressedGrip;
 169     int m_pressedRoleIndex;
 170     QPointF m_pressedMousePos;
 171
 172     struct MovingRole {
 173         QPixmap pixmap;
 174         int x;
 175         int xDec;
 176         int index;
 177     };
 178     MovingRole m_movingRole;
 179 };
 180
 181 #endif