src/kitemviews/kitemlistcontroller.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 KITEMLISTCONTROLLER_H
  10 #define KITEMLISTCONTROLLER_H
  11
  12 #include "dolphin_export.h"
  13 #include "kitemset.h"
  14
  15 #include <QObject>
  16 #include <QPointF>
  17 #include <QScroller>
  18
  19 class QTimer;
  20 class KItemModelBase;
  21 class KItemListKeyboardSearchManager;
  22 class KItemListSelectionManager;
  23 class KItemListView;
  24 class KItemListWidget;
  25 class QGestureEvent;
  26 class QGraphicsSceneHoverEvent;
  27 class QGraphicsSceneDragDropEvent;
  28 class QGraphicsSceneMouseEvent;
  29 class QGraphicsSceneResizeEvent;
  30 class QGraphicsSceneWheelEvent;
  31 class QInputMethodEvent;
  32 class QKeyEvent;
  33 class QTapGesture;
  34 class QTransform;
  35
  36 /**
  37  * @brief Controls the view, model and selection of an item-list.
  38  *
  39  * For a working item-list it is mandatory to set a compatible view and model
  40  * with KItemListController::setView() and KItemListController::setModel().
  41  *
  42  * @see KItemListView
  43  * @see KItemModelBase
  44  * @see KItemListSelectionManager
  45  */
  46 class DOLPHIN_EXPORT KItemListController : public QObject
  47 {
  48     Q_OBJECT
  49     Q_PROPERTY(KItemModelBase* model READ model WRITE setModel)
  50     Q_PROPERTY(KItemListView *view READ view WRITE setView)
  51     Q_PROPERTY(SelectionBehavior selectionBehavior READ selectionBehavior WRITE setSelectionBehavior)
  52     Q_PROPERTY(AutoActivationBehavior autoActivationBehavior READ autoActivationBehavior WRITE setAutoActivationBehavior)
  53     Q_PROPERTY(MouseDoubleClickAction mouseDoubleClickAction READ mouseDoubleClickAction WRITE setMouseDoubleClickAction)
  54
  55 public:
  56     enum SelectionBehavior {
  57         NoSelection,
  58         SingleSelection,
  59         MultiSelection
  60     };
  61     Q_ENUM(SelectionBehavior)
  62
  63     enum AutoActivationBehavior {
  64         ActivationAndExpansion,
  65         ExpansionOnly
  66     };
  67
  68     enum MouseDoubleClickAction {
  69         ActivateAndExpandItem,
  70         ActivateItemOnly
  71     };
  72
  73     /**
  74      * @param model  Model of the controller. The ownership is passed to the controller.
  75      * @param view   View of the controller. The ownership is passed to the controller.
  76      * @param parent Optional parent object.
  77      */
  78     KItemListController(KItemModelBase* model, KItemListView* view, QObject* parent = nullptr);
  79     ~KItemListController() override;
  80
  81     void setModel(KItemModelBase* model);
  82     KItemModelBase* model() const;
  83
  84     void setView(KItemListView* view);
  85     KItemListView* view() const;
  86
  87     KItemListSelectionManager* selectionManager() const;
  88
  89     void setSelectionBehavior(SelectionBehavior behavior);
  90     SelectionBehavior selectionBehavior() const;
  91
  92     void setAutoActivationBehavior(AutoActivationBehavior behavior);
  93     AutoActivationBehavior autoActivationBehavior() const;
  94
  95     void setMouseDoubleClickAction(MouseDoubleClickAction action);
  96     MouseDoubleClickAction mouseDoubleClickAction() const;
  97
  98     int indexCloseToMousePressedPosition() const;
  99
 100     /**
 101      * Sets the delay in milliseconds when dragging an object above an item
 102      * until the item gets activated automatically. A value of -1 indicates
 103      * that no automatic activation will be done at all (= default value).
 104      *
 105      * The hovered item must support dropping (see KItemModelBase::supportsDropping()),
 106      * otherwise the automatic activation is not available.
 107      *
 108      * After activating the item the signal itemActivated() will be
 109      * emitted. If the view supports the expanding of items
 110      * (KItemListView::supportsItemExpanding() returns true) and the item
 111      * itself is expandable (see KItemModelBase::isExpandable()) then instead
 112      * of activating the item it gets expanded instead (see
 113      * KItemModelBase::setExpanded()).
 114      */
 115     void setAutoActivationDelay(int delay);
 116     int autoActivationDelay() const;
 117
 118     /**
 119      * If set to true, the signals itemActivated() and itemsActivated() are emitted
 120      * after a single-click of the left mouse button. If set to false (the default),
 121      * the setting from style()->styleHint(QStyle::SH_ItemView_ActivateItemOnSingleClick) is used.
 122      */
 123     void setSingleClickActivationEnforced(bool singleClick);
 124     bool singleClickActivationEnforced() const;
 125
 126     bool processEvent(QEvent* event, const QTransform& transform);
 127
 128 signals:
 129     /**
 130      * Is emitted if exactly one item has been activated by e.g. a mouse-click
 131      * or by pressing Return/Enter.
 132      */
 133     void itemActivated(int index);
 134
 135     /**
 136      * Is emitted if more than one item has been activated by pressing Return/Enter
 137      * when having a selection.
 138      */
 139     void itemsActivated(const KItemSet& indexes);
 140
 141     void itemMiddleClicked(int index);
 142
 143     /**
 144      * Emitted if a context-menu is requested for the item with
 145      * the index \a index. It is assured that the index is valid.
 146      */
 147     void itemContextMenuRequested(int index, const QPointF& pos);
 148
 149     /**
 150      * Emitted if a context-menu is requested for the KItemListView.
 151      */
 152     void viewContextMenuRequested(const QPointF& pos);
 153
 154     /**
 155      * Emitted if a context-menu is requested for the header of the KItemListView.
 156      */
 157     void headerContextMenuRequested(const QPointF& pos);
 158
 159     /**
 160      * Is emitted if the item with the index \p index gets hovered.
 161      */
 162     void itemHovered(int index);
 163
 164     /**
 165      * Is emitted if the item with the index \p index gets unhovered.
 166      * It is assured that the signal itemHovered() for this index
 167      * has been emitted before.
 168      */
 169     void itemUnhovered(int index);
 170
 171     /**
 172      * Is emitted if a mouse-button has been pressed above an item.
 173      * If the index is smaller than 0, the mouse-button has been pressed
 174      * above the viewport.
 175      */
 176     void mouseButtonPressed(int itemIndex, Qt::MouseButtons buttons);
 177
 178     /**
 179      * Is emitted if a mouse-button has been released above an item.
 180      * It is assured that the signal mouseButtonPressed() has been emitted before.
 181      * If the index is smaller than 0, the mouse-button has been pressed
 182      * above the viewport.
 183      */
 184     void mouseButtonReleased(int itemIndex, Qt::MouseButtons buttons);
 185
 186     void itemExpansionToggleClicked(int index);
 187
 188     /**
 189      * Is emitted if a drop event is done above the item with the index
 190      * \a index. If \a index is < 0 the drop event is done above an
 191      * empty area of the view.
 192      * TODO: Introduce a new signal viewDropEvent(QGraphicsSceneDragDropEvent),
 193      *       which is emitted if the drop event occurs on an empty area in
 194      *       the view, and make sure that index is always >= 0 in itemDropEvent().
 195      */
 196     void itemDropEvent(int index, QGraphicsSceneDragDropEvent* event);
 197
 198     /**
 199      * Is emitted if a drop event is done between the item with the index
 200      * \a index and the previous item.
 201      */
 202     void aboveItemDropEvent(int index, QGraphicsSceneDragDropEvent* event);
 203
 204     /**
 205      * Is emitted if the Escape key is pressed.
 206      */
 207     void escapePressed();
 208
 209     void modelChanged(KItemModelBase* current, KItemModelBase* previous);
 210     void viewChanged(KItemListView* current, KItemListView* previous);
 211
 212     void selectedItemTextPressed(int index);
 213
 214     void scrollerStop();
 215     void increaseZoom();
 216     void decreaseZoom();
 217     void swipeUp();
 218
 219 public slots:
 220     void slotStateChanged(QScroller::State newState);
 221
 222 private slots:
 223     void slotViewScrollOffsetChanged(qreal current, qreal previous);
 224
 225     /**
 226      * Is invoked when the rubberband boundaries have been changed and will select
 227      * all items that are touched by the rubberband.
 228      */
 229     void slotRubberBandChanged();
 230
 231     void slotChangeCurrentItem(const QString& text, bool searchFromNextItem);
 232
 233     void slotAutoActivationTimeout();
 234
 235 private:
 236     /**
 237      * Creates a QDrag object and initiates a drag-operation.
 238      */
 239     void startDragging();
 240
 241     /**
 242      * @return Widget that is currently in the hovered state. 0 is returned
 243      *         if no widget is marked as hovered.
 244      */
 245     KItemListWidget* hoveredWidget() const;
 246
 247     /**
 248      * @return Widget that is below the position \a pos. 0 is returned
 249      *         if no widget is below the position.
 250      */
 251     KItemListWidget* widgetForPos(const QPointF& pos) const;
 252
 253     /**
 254      * Updates m_keyboardAnchorIndex and m_keyboardAnchorPos. If no anchor is
 255      * set, it will be adjusted to the current item. If it is set it will be
 256      * checked whether it is still valid, otherwise it will be reset to the
 257      * current item.
 258      */
 259     void updateKeyboardAnchor();
 260
 261     /**
 262      * @return Index for the next row based on \a index.
 263      *         If there is no next row \a index will be returned.
 264      */
 265     int nextRowIndex(int index) const;
 266
 267     /**
 268      * @return Index for the previous row based on  \a index.
 269      *         If there is no previous row \a index will be returned.
 270      */
 271     int previousRowIndex(int index) const;
 272
 273     /**
 274      * Helper method for updateKeyboardAnchor(), previousRowIndex() and nextRowIndex().
 275      * @return The position of the keyboard anchor for the item with the index \a index.
 276      *         If a horizontal scrolling is used the y-position of the item will be returned,
 277      *         for the vertical scrolling the x-position will be returned.
 278      */
 279     qreal keyboardAnchorPos(int index) const;
 280
 281     /**
 282      * Dependent on the selection-behavior the extendedSelectionRegion-property
 283      * of the KItemListStyleOption from the view should be adjusted: If no
 284      * rubberband selection is used the property should be enabled.
 285      */
 286     void updateExtendedSelectionRegion();
 287
 288     bool keyPressEvent(QKeyEvent* event);
 289     bool inputMethodEvent(QInputMethodEvent* event);
 290     bool mousePressEvent(QGraphicsSceneMouseEvent* event, const QTransform& transform);
 291     bool mouseMoveEvent(QGraphicsSceneMouseEvent* event, const QTransform& transform);
 292     bool mouseReleaseEvent(QGraphicsSceneMouseEvent* event, const QTransform& transform);
 293     bool mouseDoubleClickEvent(QGraphicsSceneMouseEvent* event, const QTransform& transform);
 294     bool dragEnterEvent(QGraphicsSceneDragDropEvent* event, const QTransform& transform);
 295     bool dragLeaveEvent(QGraphicsSceneDragDropEvent* event, const QTransform& transform);
 296     bool dragMoveEvent(QGraphicsSceneDragDropEvent* event, const QTransform& transform);
 297     bool dropEvent(QGraphicsSceneDragDropEvent* event, const QTransform& transform);
 298     bool hoverEnterEvent(QGraphicsSceneHoverEvent* event, const QTransform& transform);
 299     bool hoverMoveEvent(QGraphicsSceneHoverEvent* event, const QTransform& transform);
 300     bool hoverLeaveEvent(QGraphicsSceneHoverEvent* event, const QTransform& transform);
 301     bool wheelEvent(QGraphicsSceneWheelEvent* event, const QTransform& transform);
 302     bool resizeEvent(QGraphicsSceneResizeEvent* event, const QTransform& transform);
 303     bool gestureEvent(QGestureEvent* event, const QTransform& transform);
 304     void tapTriggered(QTapGesture* tap, const QTransform& transform);
 305     void tapAndHoldTriggered(QGestureEvent* event, const QTransform& transform);
 306     void pinchTriggered(QGestureEvent* event, const QTransform& transform);
 307     void swipeTriggered(QGestureEvent* event, const QTransform& transform);
 308     void twoFingerTapTriggered(QGestureEvent* event, const QTransform& transform);
 309     bool onPress(const QPoint& screenPos, const QPointF& pos, const Qt::KeyboardModifiers modifiers, const Qt::MouseButtons buttons);
 310     bool onRelease(const QPointF& pos, const Qt::KeyboardModifiers modifiers, const Qt::MouseButtons buttons, bool touch);
 311     void startRubberBand();
 312
 313 private:
 314     bool m_singleClickActivationEnforced;
 315     bool m_selectionTogglePressed;
 316     bool m_clearSelectionIfItemsAreNotDragged;
 317     bool m_isSwipeGesture;
 318     bool m_dragActionOrRightClick;
 319     bool m_scrollerIsScrolling;
 320     bool m_pinchGestureInProgress;
 321     bool m_mousePress;
 322     SelectionBehavior m_selectionBehavior;
 323     AutoActivationBehavior m_autoActivationBehavior;
 324     MouseDoubleClickAction m_mouseDoubleClickAction;
 325     KItemModelBase* m_model;
 326     KItemListView* m_view;
 327     KItemListSelectionManager* m_selectionManager;
 328     KItemListKeyboardSearchManager* m_keyboardManager;
 329     int m_pressedIndex;
 330     QPointF m_pressedMousePos;
 331
 332     QTimer* m_autoActivationTimer;
 333
 334     Qt::GestureType m_swipeGesture;
 335     Qt::GestureType m_twoFingerTapGesture;
 336     Qt::MouseEventSource m_lastSource;
 337
 338     /**
 339      * When starting a rubberband selection during a Shift- or Control-key has been
 340      * pressed the current selection should never be deleted. To be able to restore
 341      * the current selection it is remembered in m_oldSelection before the
 342      * rubberband gets activated.
 343      */
 344     KItemSet m_oldSelection;
 345
 346     /**
 347      * Assuming a view is given with a vertical scroll-orientation, grouped items and
 348      * a maximum of 4 columns:
 349      *
 350      *  1  2  3  4
 351      *  5  6  7
 352      *  8  9 10 11
 353      * 12 13 14
 354      *
 355      * If the current index is on 4 and key-down is pressed, then item 7 gets the current
 356      * item. Now when pressing key-down again item 11 should get the current item and not
 357      * item 10. This makes it necessary to keep track of the requested column to have a
 358      * similar behavior like in a text editor:
 359      */
 360     int m_keyboardAnchorIndex;
 361     qreal m_keyboardAnchorPos;
 362 };
 363
 364 #endif
 365
 366