src/dolphinnavigatorswidgetaction.h

   1 /*
   2     This file is part of the KDE project
   3     SPDX-FileCopyrightText: 2020 Felix Ernst <fe.a.ernst@gmail.com>
   4
   5     SPDX-License-Identifier: LGPL-2.1-only OR LGPL-3.0-only OR LicenseRef-KDE-Accepted-LGPL
   6 */
   7
   8 #ifndef DOLPHINNAVIGATORSWIDGETACTION_H
   9 #define DOLPHINNAVIGATORSWIDGETACTION_H
  10
  11 #include "dolphinurlnavigator.h"
  12
  13 #include <QPointer>
  14 #include <QSplitter>
  15 #include <QTimer>
  16 #include <QWidgetAction>
  17
  18 #include <memory>
  19
  20 class KXmlGuiWindow;
  21 class QPushButton;
  22
  23 /**
  24  * @brief QWidgetAction that allows to use DolphinUrlNavigators in a toolbar.
  25  *
  26  * This class is mainly a container that manages up to two DolphinUrlNavigator objects so they
  27  * can be added to a toolbar. It also deals with alignment.
  28  *
  29  * The structure of the defaultWidget() of this QWidgetAction is as follows:
  30  * - A QSplitter manages up to two sides which each correspond to one DolphinViewContainer.
  31  *      The secondary side only exists for split view and is created by
  32  *      createSecondaryUrlNavigator() when necessary.
  33  * - Each side is a QWidget which I call NavigatorWidget with a QHBoxLayout.
  34  * - Each NavigatorWidget consists an UrlNavigator, an emptyTrashButton, a
  35  *   networkFolderButton, and spacing.
  36  * - Only the primary navigatorWidget has leading spacing. Both have trailing spacing.
  37  *      The spacing is there to align the UrlNavigator with its DolphinViewContainer.
  38  */
  39 class DolphinNavigatorsWidgetAction : public QWidgetAction
  40 {
  41     Q_OBJECT
  42
  43 public:
  44     DolphinNavigatorsWidgetAction(QWidget *parent = nullptr);
  45
  46     /**
  47      * Adjusts the width of the spacings used to align the UrlNavigators with ViewContainers.
  48      * This can only work nicely if up-to-date geometry of ViewContainers is cached so
  49      * followViewContainersGeometry() has to have been called at least once before.
  50      */
  51     void adjustSpacing();
  52
  53     /**
  54      * The secondary UrlNavigator is only created on-demand. Such an action is not necessary
  55      * for the primary UrlNavigator which is created preemptively.
  56      *
  57      * This method should preferably only be called when:
  58      * - Split view is activated in the active tab
  59      * OR
  60      * - A switch to a tab that is already in split view mode is occurring
  61      */
  62     void createSecondaryUrlNavigator();
  63
  64     /**
  65      * Notify this widget of changes in geometry of the ViewContainers it tries to be
  66      * aligned with.
  67      */
  68     void followViewContainersGeometry(QWidget *primaryViewContainer,
  69                                       QWidget *secondaryViewContainer = nullptr);
  70
  71     bool isInToolbar() const;
  72
  73     /**
  74      * @return the primary UrlNavigator.
  75      */
  76     DolphinUrlNavigator *primaryUrlNavigator() const;
  77     /**
  78      * @return the secondary UrlNavigator and nullptr if it doesn't exist.
  79      */
  80     DolphinUrlNavigator *secondaryUrlNavigator() const;
  81
  82     /**
  83      * Change the visibility of the secondary UrlNavigator including spacing.
  84      * @param visible Setting this to false will completely hide the secondary side of this
  85      *                WidgetAction's QSplitter making the QSplitter effectively disappear.
  86      */
  87     void setSecondaryNavigatorVisible(bool visible);
  88
  89 protected:
  90     /**
  91      * There should always ever be one navigatorsWidget for this action so
  92      * this method always returns the same widget and reparents it.
  93      * You normally don't have to use this method directly because
  94      * QWidgetAction::requestWidget() is used to obtain the navigatorsWidget
  95      * and to steal it from wherever it was prior.
  96      * @param parent the new parent of the navigatorsWidget.
  97      */
  98     QWidget *createWidget(QWidget *parent) override;
  99
 100     /** @see QWidgetAction::deleteWidget() */
 101     void deleteWidget(QWidget *widget) override;
 102
 103 private:
 104     /**
 105      * In Left-to-right languages the Primary side will be the left one.
 106      */
 107     enum Side {
 108         Primary,
 109         Secondary
 110     };
 111     /**
 112      * Used to create the navigatorWidgets for both sides of the QSplitter.
 113      */
 114     QWidget *createNavigatorWidget(Side side) const;
 115
 116     /**
 117      * Used to retrieve the emptyTrashButtons for the navigatorWidgets on both sides.
 118      */
 119     QPushButton *emptyTrashButton(Side side);
 120
 121     /**
 122      * Creates a new empty trash button.
 123      * @param urlNavigator Only when this UrlNavigator shows the trash directory
 124      *                     will the button be visible.
 125      * @param parent       Aside from the usual QObject deletion mechanisms,
 126      *                     this parameter influences the positioning of dialog windows
 127      *                     pertaining to this trash button.
 128      */
 129     QPushButton *newEmptyTrashButton(const DolphinUrlNavigator *urlNavigator, QWidget *parent) const;
 130
 131     /**
 132      * Used to retrieve the networkFolderButtons for the navigatorWidgets on
 133      * both sides.
 134      */
 135     QPushButton *networkFolderButton(Side side);
 136
 137     /**
 138      * Creates a new add "network folder" button.
 139      * @param urlNavigator Only when this UrlNavigator shows the remote directory
 140      *                     will the button be visible.
 141      * @param parent       The object that should be the button's parent.
 142      */
 143     QPushButton *newNetworkFolderButton(const DolphinUrlNavigator *urlNavigator, QWidget *parent) const;
 144
 145     enum Position {
 146         Leading,
 147         Trailing
 148     };
 149     /**
 150      * Used to retrieve both the leading and trailing spacing for the navigatorWidgets
 151      * on both sides. A secondary leading spacing does not exist.
 152      */
 153     QWidget *spacing(Side side, Position position) const;
 154
 155     /**
 156      * Sets this action's text depending on the amount of visible UrlNavigators.
 157      */
 158     void updateText();
 159
 160     /**
 161      * The defaultWidget() of this QWidgetAction.
 162      */
 163     std::unique_ptr<QSplitter> m_splitter;
 164
 165     /**
 166      * adjustSpacing() has to be called slightly later than when urlChanged is emitted.
 167      * This timer bridges that time.
 168      */
 169     std::unique_ptr<QTimer> m_adjustSpacingTimer;
 170
 171     /**
 172      * Extracts the geometry information needed by adjustSpacing() from
 173      * ViewContainers. They are also monitored for size changes which
 174      * will lead to adjustSpacing() calls.
 175      */
 176     class ViewGeometriesHelper : public QObject
 177     {
 178     public:
 179         /**
 180          * @param navigatorsWidget       The QWidget of the navigatorsWidgetAction.
 181          * @param navigatorsWidgetAction is only used to call adjustSpacing() whenever that is
 182          *                               deemed necessary.
 183          */
 184         ViewGeometriesHelper(QWidget *navigatorsWidget, DolphinNavigatorsWidgetAction *navigatorsWidgetAction);
 185
 186         /**
 187          * Calls m_navigatorsWidgetAction::adjustSpacing() when a watched object is resized.
 188          */
 189         bool eventFilter(QObject *watched, QEvent *event) override;
 190
 191         /**
 192          * Sets the ViewContainers whose geometry is obtained when viewGeometries() is called.
 193          */
 194         void setViewContainers(QWidget *primaryViewContainer,
 195                                QWidget *secondaryViewContainer = nullptr);
 196
 197         struct Geometries {
 198             int globalXOfNavigatorsWidget;
 199             int globalXOfPrimary;
 200             int widthOfPrimary;
 201             int globalXOfSecondary;
 202             int widthOfSecondary;
 203         };
 204         /**
 205          * @return a Geometries struct that contains values adjustSpacing() requires.
 206          */
 207         Geometries viewGeometries();
 208
 209     private:
 210         QWidget *m_navigatorsWidget;
 211         /** Is only used to call adjustSpacing() whenever that is deemed necessary. */
 212         DolphinNavigatorsWidgetAction *m_navigatorsWidgetAction;
 213
 214         QPointer<QWidget> m_primaryViewContainer;
 215         QPointer<QWidget> m_secondaryViewContainer;
 216     };
 217
 218     ViewGeometriesHelper m_viewGeometriesHelper;
 219
 220     /**
 221      * Used to check if the window has been resized.
 222      * @see ViewGeometriesHelper::eventFilter() for why this is needed.
 223      */
 224     int m_previousWindowWidth = -1;
 225 };
 226
 227 #endif // DOLPHINNAVIGATORSWIDGETACTION_H