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 class QTouchEvent;
  36
  37 /**
  38  * @brief Controls the view, model and selection of an item-list.
  39  *
  40  * For a working item-list it is mandatory to set a compatible view and model
  41  * with KItemListController::setView() and KItemListController::setModel().
  42  *
  43  * @see KItemListView
  44  * @see KItemModelBase
  45  * @see KItemListSelectionManager
  46  */
  47 class DOLPHIN_EXPORT KItemListController : public QObject
  48 {
  49     Q_OBJECT
  50     Q_PROPERTY(KItemModelBase* model READ model WRITE setModel)
  51     Q_PROPERTY(KItemListView *view READ view WRITE setView)
  52     Q_PROPERTY(SelectionBehavior selectionBehavior READ selectionBehavior WRITE setSelectionBehavior)
  53     Q_PROPERTY(AutoActivationBehavior autoActivationBehavior READ autoActivationBehavior WRITE setAutoActivationBehavior)
  54     Q_PROPERTY(MouseDoubleClickAction mouseDoubleClickAction READ mouseDoubleClickAction WRITE setMouseDoubleClickAction)
  55
  56 public:
  57     enum SelectionBehavior {
  58         NoSelection,
  59         SingleSelection,
  60         MultiSelection
  61     };
  62     Q_ENUM(SelectionBehavior)
  63
  64     enum AutoActivationBehavior {
  65         ActivationAndExpansion,
  66         ExpansionOnly
  67     };
  68
  69     enum MouseDoubleClickAction {
  70         ActivateAndExpandItem,
  71         ActivateItemOnly
  72     };
  73
  74     /**
  75      * @param model  Model of the controller. The ownership is passed to the controller.
  76      * @param view   View of the controller. The ownership is passed to the controller.
  77      * @param parent Optional parent object.
  78      */
  79     KItemListController(KItemModelBase* model, KItemListView* view, QObject* parent = nullptr);
  80     ~KItemListController() override;
  81
  82     void setModel(KItemModelBase* model);
  83     KItemModelBase* model() const;
  84
  85     void setView(KItemListView* view);
  86     KItemListView* view() const;
  87
  88     KItemListSelectionManager* selectionManager() const;
  89
  90     void setSelectionBehavior(SelectionBehavior behavior);
  91     SelectionBehavior selectionBehavior() const;
  92
  93     void setAutoActivationBehavior(AutoActivationBehavior behavior);
  94     AutoActivationBehavior autoActivationBehavior() const;
  95
  96     void setMouseDoubleClickAction(MouseDoubleClickAction action);
  97     MouseDoubleClickAction mouseDoubleClickAction() const;
  98
  99     int indexCloseToMousePressedPosition() const;
 100
 101     /**
 102      * Sets the delay in milliseconds when dragging an object above an item
 103      * until the item gets activated automatically. A value of -1 indicates
 104      * that no automatic activation will be done at all (= default value).
 105      *
 106      * The hovered item must support dropping (see KItemModelBase::supportsDropping()),
 107      * otherwise the automatic activation is not available.
 108      *
 109      * After activating the item the signal itemActivated() will be
 110      * emitted. If the view supports the expanding of items
 111      * (KItemListView::supportsItemExpanding() returns true) and the item
 112      * itself is expandable (see KItemModelBase::isExpandable()) then instead
 113      * of activating the item it gets expanded instead (see
 114      * KItemModelBase::setExpanded()).
 115      */
 116     void setAutoActivationDelay(int delay);
 117     int autoActivationDelay() const;
 118
 119     /**
 120      * If set to true, the signals itemActivated() and itemsActivated() are emitted
 121      * after a single-click of the left mouse button. If set to false (the default),
 122      * the setting from style()->styleHint(QStyle::SH_ItemView_ActivateItemOnSingleClick) is used.
 123      */
 124     void setSingleClickActivationEnforced(bool singleClick);
 125     bool singleClickActivationEnforced() const;
 126
 127     bool processEvent(QEvent* event, const QTransform& transform);
 128
 129 Q_SIGNALS:
 130     /**
 131      * Is emitted if exactly one item has been activated by e.g. a mouse-click
 132      * or by pressing Return/Enter.
 133      */
 134     void itemActivated(int index);
 135
 136     /**
 137      * Is emitted if more than one item has been activated by pressing Return/Enter
 138      * when having a selection.
 139      */
 140     void itemsActivated(const KItemSet& indexes);
 141
 142     void itemMiddleClicked(int index);
 143
 144     /**
 145      * Emitted if a context-menu is requested for the item with
 146      * the index \a index. It is assured that the index is valid.
 147      */
 148     void itemContextMenuRequested(int index, const QPointF& pos);
 149
 150     /**
 151      * Emitted if a context-menu is requested for the KItemListView.
 152      */
 153     void viewContextMenuRequested(const QPointF& pos);
 154
 155     /**
 156      * Emitted if a context-menu is requested for the header of the KItemListView.
 157      */
 158     void headerContextMenuRequested(const QPointF& pos);
 159
 160     /**
 161      * Is emitted if the item with the index \p index gets hovered.
 162      */
 163     void itemHovered(int index);
 164
 165     /**
 166      * Is emitted if the item with the index \p index gets unhovered.
 167      * It is assured that the signal itemHovered() for this index
 168      * has been emitted before.
 169      */
 170     void itemUnhovered(int index);
 171
 172     /**
 173      * Is emitted if a mouse-button has been pressed above an item.
 174      * If the index is smaller than 0, the mouse-button has been pressed
 175      * above the viewport.
 176      */
 177     void mouseButtonPressed(int itemIndex, Qt::MouseButtons buttons);
 178
 179     /**
 180      * Is emitted if a mouse-button has been released above an item.
 181      * It is assured that the signal mouseButtonPressed() has been emitted before.
 182      * If the index is smaller than 0, the mouse-button has been pressed
 183      * above the viewport.
 184      */
 185     void mouseButtonReleased(int itemIndex, Qt::MouseButtons buttons);
 186
 187     void itemExpansionToggleClicked(int index);
 188
 189     /**
 190      * Is emitted if a drop event is done above the item with the index
 191      * \a index. If \a index is < 0 the drop event is done above an
 192      * empty area of the view.
 193      * TODO: Introduce a new signal viewDropEvent(QGraphicsSceneDragDropEvent),
 194      *       which is emitted if the drop event occurs on an empty area in
 195      *       the view, and make sure that index is always >= 0 in itemDropEvent().
 196      */
 197     void itemDropEvent(int index, QGraphicsSceneDragDropEvent* event);
 198
 199     /**
 200      * Is emitted if a drop event is done between the item with the index
 201      * \a index and the previous item.
 202      */
 203     void aboveItemDropEvent(int index, QGraphicsSceneDragDropEvent* event);
 204
 205     /**
 206      * Is emitted if the Escape key is pressed.
 207      */
 208     void escapePressed();
 209
 210     void modelChanged(KItemModelBase* current, KItemModelBase* previous);
 211     void viewChanged(KItemListView* current, KItemListView* previous);
 212
 213     void selectedItemTextPressed(int index);
 214
 215     void scrollerStop();
 216     void increaseZoom();
 217     void decreaseZoom();
 218     void swipeUp();
 219
 220 public Q_SLOTS:
 221     void slotStateChanged(QScroller::State newState);
 222
 223 private Q_SLOTS:
 224     void slotViewScrollOffsetChanged(qreal current, qreal previous);
 225
 226     /**
 227      * Is invoked when the rubberband boundaries have been changed and will select
 228      * all items that are touched by the rubberband.
 229      */
 230     void slotRubberBandChanged();
 231
 232     void slotChangeCurrentItem(const QString& text, bool searchFromNextItem);
 233
 234     void slotAutoActivationTimeout();
 235
 236 private:
 237     /**
 238      * Creates a QDrag object and initiates a drag-operation.
 239      */
 240     void startDragging();
 241
 242     /**
 243      * @return Widget that is currently in the hovered state. 0 is returned
 244      *         if no widget is marked as hovered.
 245      */
 246     KItemListWidget* hoveredWidget() const;
 247
 248     /**
 249      * @return Widget that is below the position \a pos. 0 is returned
 250      *         if no widget is below the position.
 251      */
 252     KItemListWidget* widgetForPos(const QPointF& pos) const;
 253
 254     /**
 255      * Updates m_keyboardAnchorIndex and m_keyboardAnchorPos. If no anchor is
 256      * set, it will be adjusted to the current item. If it is set it will be
 257      * checked whether it is still valid, otherwise it will be reset to the
 258      * current item.
 259      */
 260     void updateKeyboardAnchor();
 261
 262     /**
 263      * @return Index for the next row based on \a index.
 264      *         If there is no next row \a index will be returned.
 265      */
 266     int nextRowIndex(int index) const;
 267
 268     /**
 269      * @return Index for the previous row based on  \a index.
 270      *         If there is no previous row \a index will be returned.
 271      */
 272     int previousRowIndex(int index) const;
 273
 274     /**
 275      * Helper method for updateKeyboardAnchor(), previousRowIndex() and nextRowIndex().
 276      * @return The position of the keyboard anchor for the item with the index \a index.
 277      *         If a horizontal scrolling is used the y-position of the item will be returned,
 278      *         for the vertical scrolling the x-position will be returned.
 279      */
 280     qreal keyboardAnchorPos(int index) const;
 281
 282     /**
 283      * Dependent on the selection-behavior the extendedSelectionRegion-property
 284      * of the KItemListStyleOption from the view should be adjusted: If no
 285      * rubberband selection is used the property should be enabled.
 286      */
 287     void updateExtendedSelectionRegion();
 288
 289     bool keyPressEvent(QKeyEvent* event);
 290     bool inputMethodEvent(QInputMethodEvent* event);
 291     bool mousePressEvent(QGraphicsSceneMouseEvent* event, const QTransform& transform);
 292     bool mouseMoveEvent(QGraphicsSceneMouseEvent* event, const QTransform& transform);
 293     bool mouseReleaseEvent(QGraphicsSceneMouseEvent* event, const QTransform& transform);
 294     bool mouseDoubleClickEvent(QGraphicsSceneMouseEvent* event, const QTransform& transform);
 295     bool dragEnterEvent(QGraphicsSceneDragDropEvent* event, const QTransform& transform);
 296     bool dragLeaveEvent(QGraphicsSceneDragDropEvent* event, const QTransform& transform);
 297     bool dragMoveEvent(QGraphicsSceneDragDropEvent* event, const QTransform& transform);
 298     bool dropEvent(QGraphicsSceneDragDropEvent* event, const QTransform& transform);
 299     bool hoverEnterEvent(QGraphicsSceneHoverEvent* event, const QTransform& transform);
 300     bool hoverMoveEvent(QGraphicsSceneHoverEvent* event, const QTransform& transform);
 301     bool hoverLeaveEvent(QGraphicsSceneHoverEvent* event, const QTransform& transform);
 302     bool wheelEvent(QGraphicsSceneWheelEvent* event, const QTransform& transform);
 303     bool resizeEvent(QGraphicsSceneResizeEvent* event, const QTransform& transform);
 304     bool gestureEvent(QGestureEvent* event, const QTransform& transform);
 305     bool touchBeginEvent(QTouchEvent* event, const QTransform& transform);
 306     void tapTriggered(QTapGesture* tap, const QTransform& transform);
 307     void tapAndHoldTriggered(QGestureEvent* event, const QTransform& transform);
 308     void pinchTriggered(QGestureEvent* event, const QTransform& transform);
 309     void swipeTriggered(QGestureEvent* event, const QTransform& transform);
 310     void twoFingerTapTriggered(QGestureEvent* event, const QTransform& transform);
 311     bool onPress(const QPoint& screenPos, const QPointF& pos, const Qt::KeyboardModifiers modifiers, const Qt::MouseButtons buttons);
 312     bool onRelease(const QPointF& pos, const Qt::KeyboardModifiers modifiers, const Qt::MouseButtons buttons, bool touch);
 313     void startRubberBand();
 314
 315 private:
 316     bool m_singleClickActivationEnforced;
 317     bool m_selectionTogglePressed;
 318     bool m_clearSelectionIfItemsAreNotDragged;
 319     bool m_isSwipeGesture;
 320     bool m_dragActionOrRightClick;
 321     bool m_scrollerIsScrolling;
 322     bool m_pinchGestureInProgress;
 323     bool m_mousePress;
 324     bool m_isTouchEvent;
 325     SelectionBehavior m_selectionBehavior;
 326     AutoActivationBehavior m_autoActivationBehavior;
 327     MouseDoubleClickAction m_mouseDoubleClickAction;
 328     KItemModelBase* m_model;
 329     KItemListView* m_view;
 330     KItemListSelectionManager* m_selectionManager;
 331     KItemListKeyboardSearchManager* m_keyboardManager;
 332     int m_pressedIndex;
 333     QPointF m_pressedMousePos;
 334
 335     QTimer* m_autoActivationTimer;
 336
 337     Qt::GestureType m_swipeGesture;
 338     Qt::GestureType m_twoFingerTapGesture;
 339
 340     /**
 341      * When starting a rubberband selection during a Shift- or Control-key has been
 342      * pressed the current selection should never be deleted. To be able to restore
 343      * the current selection it is remembered in m_oldSelection before the
 344      * rubberband gets activated.
 345      */
 346     KItemSet m_oldSelection;
 347
 348     /**
 349      * Assuming a view is given with a vertical scroll-orientation, grouped items and
 350      * a maximum of 4 columns:
 351      *
 352      *  1  2  3  4
 353      *  5  6  7
 354      *  8  9 10 11
 355      * 12 13 14
 356      *
 357      * If the current index is on 4 and key-down is pressed, then item 7 gets the current
 358      * item. Now when pressing key-down again item 11 should get the current item and not
 359      * item 10. This makes it necessary to keep track of the requested column to have a
 360      * similar behavior like in a text editor:
 361      */
 362     int m_keyboardAnchorIndex;
 363     qreal m_keyboardAnchorPos;
 364 };
 365
 366 #endif
 367
 368