qtquick: Support setting floating window flags from QML

Author: iamsergio

src/KDDockWidgets.h

@@ -361,9 +361,9 @@ enum StackOption {
 Q_DECLARE_FLAGS(StackOptions, StackOption)
 Q_ENUM_NS(StackOptions)
 
-/// @internal
+/// @brief Per-dock-widget flags controlling the floating window's title bar buttons and behaviour
 enum class FloatingWindowFlag {
-    None = 0,
+    NoFlags = 0,
     FromGlobalConfig = 1, // KDDockWidgets::Config is used instead
     TitleBarHasMinimizeButton = 2,
     TitleBarHasMaximizeButton = 4,
@@ -377,6 +377,7 @@ enum class FloatingWindowFlag {
     StartsMinimized = 1024
 };
 Q_DECLARE_FLAGS(FloatingWindowFlags, FloatingWindowFlag)
+Q_ENUM_NS(FloatingWindowFlags)
 
 /// @internal
 enum class WindowState {

src/qtquick/DockWidgetInstantiator.cpp

@@ -33,6 +33,7 @@ class DockWidgetInstantiator::Private
     QPointer<Core::DockWidget> m_dockWidget;
     QVector<QString> m_affinities;
     KDDockWidgets::DockWidgetOptions m_options = KDDockWidgets::DockWidgetOption_None;
+    KDDockWidgets::FloatingWindowFlags m_floatingWindowFlags = KDDockWidgets::FloatingWindowFlag::FromGlobalConfig;
 #if QT_VERSION >= QT_VERSION_CHECK(6, 0, 0)
     QVariantMap m_userData;
     KDBindings::ScopedConnection userDataConnection;
@@ -277,6 +278,22 @@ void DockWidgetInstantiator::setOptions(KDDockWidgets::DockWidgetOptions options
     }
 }
 
+KDDockWidgets::FloatingWindowFlags DockWidgetInstantiator::floatingWindowFlags() const
+{
+    return d->m_dockWidget ? d->m_dockWidget->floatingWindowFlags() : d->m_floatingWindowFlags;
+}
+
+void DockWidgetInstantiator::setFloatingWindowFlags(KDDockWidgets::FloatingWindowFlags flags)
+{
+    if (d->m_floatingWindowFlags != flags) {
+        d->m_floatingWindowFlags = flags;
+        if (d->m_dockWidget) {
+            d->m_dockWidget->setFloatingWindowFlags(flags);
+        }
+        Q_EMIT floatingWindowFlagsChanged(flags);
+    }
+}
+
 KDDockWidgets::CloseReason DockWidgetInstantiator::lastCloseReason() const
 {
     return d->m_dockWidget ? d->m_dockWidget->lastCloseReason() : KDDockWidgets::CloseReason::Unspecified;
@@ -342,6 +359,7 @@ void DockWidgetInstantiator::componentComplete()
         d->m_dockWidget->setFloating(d->m_isFloating.value());
 
     d->m_dockWidget->setAffinities(d->m_affinities);
+    d->m_dockWidget->setFloatingWindowFlags(d->m_floatingWindowFlags);
 
 #if QT_VERSION >= QT_VERSION_CHECK(6, 0, 0)
     d->m_dockWidget->setUserData(d->m_userData);

src/qtquick/DockWidgetInstantiator.h

@@ -45,6 +45,8 @@ class DockWidgetInstantiator : public QQuickItem
     Q_PROPERTY(bool isOpen READ isOpen NOTIFY isOpenChanged)
     Q_PROPERTY(QVector<QString> affinities READ affinities WRITE setAffinities NOTIFY affinitiesChanged)
     Q_PROPERTY(KDDockWidgets::DockWidgetOptions options READ options WRITE setOptions NOTIFY optionsChanged)
+    Q_PROPERTY(KDDockWidgets::FloatingWindowFlags floatingWindowFlags READ floatingWindowFlags WRITE
+                   setFloatingWindowFlags NOTIFY floatingWindowFlagsChanged)
     Q_PROPERTY(KDDockWidgets::CloseReason lastCloseReason READ lastCloseReason NOTIFY lastCloseReasonChanged)
 #if QT_VERSION >= QT_VERSION_CHECK(6, 0, 0)
     Q_PROPERTY(QVariantMap userData READ userData WRITE setUserData NOTIFY userDataChanged)
@@ -76,6 +78,9 @@ class DockWidgetInstantiator : public QQuickItem
     KDDockWidgets::DockWidgetOptions options() const;
     void setOptions(KDDockWidgets::DockWidgetOptions);
 
+    KDDockWidgets::FloatingWindowFlags floatingWindowFlags() const;
+    void setFloatingWindowFlags(KDDockWidgets::FloatingWindowFlags);
+
     KDDockWidgets::CloseReason lastCloseReason() const;
 
 #if QT_VERSION >= QT_VERSION_CHECK(6, 0, 0)
@@ -125,6 +130,7 @@ class DockWidgetInstantiator : public QQuickItem
     void closed();
     void guestViewChanged(QQuickItem *);
     void optionsChanged(KDDockWidgets::DockWidgetOptions);
+    void floatingWindowFlagsChanged(KDDockWidgets::FloatingWindowFlags);
     void isFocusedChanged(bool);
     void isOverlayedChanged(bool);
     void isFloatingChanged(bool);

tests/main_titleBarHasMinimizeButton.qml

@@ -0,0 +1,42 @@
+/*
+  This file is part of KDDockWidgets.
+
+  SPDX-FileCopyrightText: 2026 Klarälvdalens Datakonsult AB, a KDAB Group company <info@kdab.com>
+  Author: Sérgio Martins <sergio.martins@kdab.com>
+
+  SPDX-License-Identifier: GPL-2.0-only OR GPL-3.0-only
+
+  Contact KDAB at <info@kdab.com> for commercial licensing options.
+*/
+
+import QtQuick 2.6
+import QtQuick.Controls 2.12
+import com.kdab.dockwidgets 2.0 as KDDW
+
+ApplicationWindow {
+    visible: true
+    width: 1000
+    height: 800
+
+    KDDW.DockingArea {
+        anchors.fill: parent
+
+        uniqueName: "MyWindowName-titleBarHasMinimizeButton"
+
+        KDDW.DockWidget {
+            id: dock1
+            uniqueName: "dock1"
+            floatingWindowFlags: KDDW.KDDockWidgets.FloatingWindowFlags.TitleBarHasMinimizeButton
+
+            Rectangle {
+                anchors.fill: parent
+                color: "blue"
+            }
+        }
+
+        Component.onCompleted: {
+            // Never added to the layout, so it starts out floating.
+            dock1.open();
+        }
+    }
+}

tests/qtquick/tst_qtquick.cpp

@@ -79,6 +79,10 @@ private Q_SLOTS:
     void tst_mainWindowNativeClose();
     void tst_setViewFactory();
     void tst_quickWindowCreationCallback();
+
+    /// Tests that DockWidget.floatingWindowFlags set from QML is honoured, using
+    /// FloatingWindowFlag_TitleBarHasMinimizeButton as the observable case.
+    void tst_floatingWindowFlagsFromQml();
 };
 
 
@@ -616,6 +620,23 @@ void TestQtQuick::tst_quickWindowCreationCallback()
     QtQuick::FloatingWindow::setQuickWindowCreationCallback(nullptr);
 }
 
+void TestQtQuick::tst_floatingWindowFlagsFromQml()
+{
+    EnsureTopLevelsDeleted e;
+    QQmlApplicationEngine engine(":/main_titleBarHasMinimizeButton.qml");
+
+    auto dock1 = DockRegistry::self()->dockByName("dock1");
+    QVERIFY(dock1);
+
+    QVERIFY(dock1->floatingWindowFlags() & FloatingWindowFlag::TitleBarHasMinimizeButton);
+
+    QVERIFY(dock1->isFloating());
+    auto fw = dock1->floatingWindow();
+    QVERIFY(fw);
+
+    QVERIFY(fw->titleBar()->supportsMinimizeButton());
+}
+
 int main(int argc, char *argv[])
 {
 #ifdef KDDW_HAS_SPDLOG

tests/test_resources.qrc

@@ -23,5 +23,6 @@
         <file>MyRectangle.qml</file>
 	    <file>main_tst_focusBetweenTabs.qml</file>
         <file>MyRectangle2.qml</file>
+        <file>main_titleBarHasMinimizeButton.qml</file>
 </qresource>
 </RCC>