Introduced Config::setDropIndicatorsInhibited(bool)

Allows you to disable support for drop indicators while dragging

Changelog

@@ -12,6 +12,8 @@
     dock widget docked. Tabbed cases are more difficult since QStackedLayout doesn't
     propagate size constraints.
   - Added MainWindowBase::frameCountChanged()
+  - Introduced Config::setDropIndicatorsInhibited(), which allows you to disable support
+  for drop indicators while dragging.
 
 * v1.3.1 (unreleased)
   - Improve restoring layout when RestoreOption_RelativeToMainWindow is used (#171)

examples/dockwidgets/MyMainWindow.cpp

@@ -12,6 +12,7 @@
 #include "MyMainWindow.h"
 #include "MyWidget.h"
 
+#include <kddockwidgets/Config.h>
 #include <kddockwidgets/LayoutSaver.h>
 
 #include <QMenu>
@@ -69,8 +70,11 @@ MyMainWindow::MyMainWindow(const QString &uniqueName, KDDockWidgets::MainWindowO
     auto menubar = menuBar();
     auto fileMenu = new QMenu(QStringLiteral("File"));
     m_toggleMenu = new QMenu(QStringLiteral("Toggle"));
+    auto miscMenu = new QMenu(QStringLiteral("Misc"));
+
     menubar->addMenu(fileMenu);
     menubar->addMenu(m_toggleMenu);
+    menubar->addMenu(miscMenu);
 
     QAction *newAction = fileMenu->addAction(QStringLiteral("New DockWidget"));
 
@@ -114,6 +118,13 @@ MyMainWindow::MyMainWindow(const QString &uniqueName, KDDockWidgets::MainWindowO
     auto quitAction = fileMenu->addAction(QStringLiteral("Quit"));
     connect(quitAction, &QAction::triggered, qApp, &QApplication::quit);
 
+    QAction *toggleDropIndicatorSupport = miscMenu->addAction(QStringLiteral("Toggle Drop Indicator Support"));
+    toggleDropIndicatorSupport->setCheckable(true);
+    toggleDropIndicatorSupport->setChecked(true);
+    connect(toggleDropIndicatorSupport, &QAction::toggled, this, [](bool checked) {
+        KDDockWidgets::Config::self().setDropIndicatorsInhibited(!checked);
+    });
+
     setAffinities({ affinityName });
     createDockWidgets();
 }

src/Config.cpp

@@ -61,6 +61,7 @@ public:
     CustomizableWidgets m_disabledPaintEvents = CustomizableWidget_None;
     qreal m_draggedWindowOpacity = Q_QNAN;
     int m_mdiPopupThreshold = 250;
+    bool m_dropIndicatorsInhibited = false;
 #ifdef KDDOCKWIDGETS_QTQUICK
     QtQuickHelpers m_qquickHelpers;
 #endif
@@ -325,4 +326,18 @@ int Config::mdiPopupThreshold() const
 {
     return d->m_mdiPopupThreshold;
 }
+
+void Config::setDropIndicatorsInhibited(bool inhibit) const
+{
+    if (d->m_dropIndicatorsInhibited != inhibit) {
+        d->m_dropIndicatorsInhibited = inhibit;
+        Q_EMIT DockRegistry::self()->dropIndicatorsInhibitedChanged(inhibit);
+    }
+}
+
+bool Config::dropIndicatorsInhibited() const
+{
+    return d->m_dropIndicatorsInhibited;
+}
+
 }

src/Config.h

@@ -182,6 +182,15 @@ public:
     ///By default it's 1.0, fully opaque
     qreal draggedWindowOpacity() const;
 
+    /// @brief Allows to disable support for drop indicators while dragging
+    /// By default drop indicators will be shown when dragging dock widgets.
+    /// This functionality can be toggled whenever you need it (it's not a startup-only setting).
+    void setDropIndicatorsInhibited(bool inhibit) const;
+
+    /// @brief Returns whether drop indicators are inhibited.
+    /// by default this is false unless you call setDropIndicatorsInhibited(true)
+    bool dropIndicatorsInhibited() const;
+
     /**
      * @brief Allows the user to intercept a docking attempt to center (tabbed) and disallow it.
      *

src/private/DockRegistry_p.h

@@ -235,6 +235,9 @@ Q_SIGNALS:
     /// @brief emitted when the MDI frame that's being resized changed
     void frameInMDIResizeChanged();
 
+    /// @brief emitted whenever Config::dropIndicatorsInhibited changes
+    void dropIndicatorsInhibitedChanged(bool inhibited);
+
 protected:
     bool eventFilter(QObject *watched, QEvent *event) override;
 private:

src/private/DropArea.cpp

@@ -180,7 +180,7 @@ void DropArea::layoutParentContainerEqually(DockWidgetBase *dw)
 
 DropIndicatorOverlayInterface::DropLocation DropArea::hover(WindowBeingDragged *draggedWindow, QPoint globalPos)
 {
-    if (!validateAffinity(draggedWindow))
+    if (Config::self().dropIndicatorsInhibited() || !validateAffinity(draggedWindow))
         return DropIndicatorOverlayInterface::DropLocation_None;
 
     if (!m_dropIndicatorOverlay) {

src/private/DropIndicatorOverlayInterface.cpp

@@ -13,6 +13,7 @@
 
 #include "Frame_p.h"
 #include "DropArea_p.h"
+#include "DockRegistry_p.h"
 
 using namespace KDDockWidgets;
 
@@ -22,6 +23,14 @@ DropIndicatorOverlayInterface::DropIndicatorOverlayInterface(DropArea *dropArea)
 {
     setVisible(false);
     setObjectName(QStringLiteral("DropIndicatorOverlayInterface"));
+
+    connect(DockRegistry::self(), &DockRegistry::dropIndicatorsInhibitedChanged, this,
+            [this](bool inhibited) {
+                if (inhibited)
+                    removeHover();
+
+                // if false then simply moving the mouse will make the drop indicators appear again
+            });
 }
 
 void DropIndicatorOverlayInterface::setWindowBeingDragged(bool is)