Expose the Window interface to QML

If we are designing our UI's windows from QML, it makes sense that we
might want to configure how they're placed from the same place.

Everything was already in place but for a few technical bits which this
change adds.

Signed-off-by: Victoria Fischer <victoria.fischer@mbition.io>

CMakeLists.txt

@@ -4,13 +4,13 @@
 cmake_minimum_required(VERSION 3.16)
 
 project(layershellqt)
-set(PROJECT_VERSION "5.26.90")
+set(PROJECT_VERSION "5.27.6")
 set(PROJECT_VERSION_MAJOR 5)
 
 set(CMAKE_C_STANDARD 99)
 
 set(QT_MIN_VERSION "5.15.2")
-set(KF5_MIN_VERSION "5.98.0")
+set(KF5_MIN_VERSION "5.102.0")
 set(KDE_COMPILERSETTINGS_LEVEL "5.82")
 
 set(CMAKE_CXX_STANDARD 17)
@@ -29,6 +29,7 @@ include(CMakePackageConfigHelpers)
 include(FeatureSummary)
 include(GenerateExportHeader)
 include(KDEClangFormat)
+include(ECMQmlModule)
 include(ECMQtDeclareLoggingCategory)
 
 

src/CMakeLists.txt

@@ -24,7 +24,8 @@ ecm_qt_declare_logging_category(LAYER_SHELL_SOURCES
 )
 
 target_sources(LayerShellQtInterface PRIVATE qwaylandlayersurface.cpp interfaces/window.cpp interfaces/shell.cpp qwaylandlayershellintegration.cpp qwaylandlayershell.cpp ${LAYER_SHELL_SOURCES})
-target_link_libraries(LayerShellQtInterface PRIVATE Qt::Gui Qt::WaylandClientPrivate Wayland::Client PkgConfig::XKBCOMMON)
+target_link_libraries(LayerShellQtInterface PUBLIC Qt::Gui)
+target_link_libraries(LayerShellQtInterface PRIVATE Qt::WaylandClientPrivate Wayland::Client PkgConfig::XKBCOMMON)
 if (TARGET Qt::XkbCommonSupportPrivate)
     target_link_libraries(LayerShellQtInterface PRIVATE Qt::XkbCommonSupportPrivate)
 endif()
@@ -68,3 +69,5 @@ install(FILES
     ${CMAKE_CURRENT_BINARY_DIR}/LayerShellQt/layershellqt_export.h
     DESTINATION ${KDE_INSTALL_INCLUDEDIR}/LayerShellQt COMPONENT Devel
 )
+
+add_subdirectory(declarative)

src/declarative/CMakeLists.txt

@@ -0,0 +1,8 @@
+# SPDX-FileCopyrightText: 2021 Aleix Pol Gonzalez <aleix.pol_gonzalez@mercedes-benz.com>
+# SPDX-License-Identifier: BSD-3-Clause
+
+ecm_add_qml_module(LayerShellQtQml URI "org.kde.layershell")
+target_sources(LayerShellQtQml PRIVATE layershellqtplugin.cpp)
+target_link_libraries(LayerShellQtQml PRIVATE Qt::Qml LayerShellQtInterface)
+
+ecm_finalize_qml_module(LayerShellQtQml DESTINATION ${KDE_INSTALL_QMLDIR})

src/declarative/layershellqtplugin.cpp

@@ -0,0 +1,24 @@
+/*
+ *   SPDX-FileCopyrightText: 2023 Aleix Pol Gonzalez <aleix.pol_gonzalez@mercedes-benz.com>
+ *
+ *   SPDX-License-Identifier: LGPL-3.0-or-later
+ */
+
+#include <QQmlExtensionPlugin>
+#include "../interfaces/window.h"
+#include <qqml.h>
+
+QML_DECLARE_TYPEINFO(LayerShellQt::Window, QML_HAS_ATTACHED_PROPERTIES)
+
+class Plugin : public QQmlExtensionPlugin
+{
+    Q_PLUGIN_METADATA(IID "org.kde.layershellqt")
+    Q_OBJECT
+public:
+    void registerTypes(const char *uri) override {
+        Q_ASSERT(QLatin1String(uri) == QLatin1String("org.kde.layershell"));
+        qmlRegisterType<LayerShellQt::Window>(uri, 1, 0, "Window");
+    }
+};
+
+#include "layershellqtplugin.moc"

src/interfaces/window.cpp

@@ -8,6 +8,7 @@
 #include <layershellqt_logging.h>
 
 #include <QPointer>
+#include <optional>
 
 using namespace LayerShellQt;
 
@@ -26,7 +27,7 @@ public:
     Window::KeyboardInteractivity keyboardInteractivity = Window::KeyboardInteractivityExclusive;
     Window::Layer layer = Window::LayerTop;
     QMargins margins;
-    QPointer<QScreen> desiredOutput;
+    std::optional<QPointer<QScreen>> desiredOutput;
 };
 
 static QMap<QWindow *, Window *> s_map;
@@ -103,7 +104,12 @@ Window::Layer Window::layer() const
 
 QScreen *Window::desiredOutput() const
 {
-    return d->desiredOutput;
+    // Don't use .value_or here to avoid a temporary QPointer
+    if (d->desiredOutput.has_value()) {
+        return d->desiredOutput.value();
+    }
+
+    return d->parentWindow->screen();
 }
 
 void Window::setDesiredOutput(QScreen *output)
@@ -120,9 +126,18 @@ Window::Window(QWindow *window)
 
 Window *Window::get(QWindow *window)
 {
+    if (!window) {
+        return nullptr;
+    }
+
     auto layerShellWindow = s_map.value(window);
     if (layerShellWindow) {
         return layerShellWindow;
     }
     return new Window(window);
 }
+
+Window *Window::qmlAttachedProperties(QObject *object)
+{
+    return get(qobject_cast<QWindow *>(object));
+}

src/interfaces/window.h

@@ -21,7 +21,15 @@ class WindowPrivate;
 class LAYERSHELLQT_EXPORT Window : public QObject
 {
     Q_OBJECT
+    Q_PROPERTY(int anchors READ anchors WRITE setAnchorsInt NOTIFY anchorsChanged)
+    Q_PROPERTY(QString scope READ scope WRITE setScope)
+    Q_PROPERTY(QMargins margins READ margins WRITE setMargins NOTIFY marginsChanged)
+    Q_PROPERTY(qint32 exclusionZone READ exclusionZone WRITE setExclusiveZone NOTIFY exclusionZoneChanged)
+    Q_PROPERTY(Layer layer READ layer WRITE setLayer NOTIFY layerChanged)
+    Q_PROPERTY(KeyboardInteractivity keyboardInteractivity READ keyboardInteractivity WRITE setKeyboardInteractivity NOTIFY keyboardInteractivityChanged)
+
 public:
+    Window(QWindow *window = nullptr);
     ~Window() override;
 
     enum Anchor {
@@ -87,12 +95,17 @@ public:
     void setScope(const QString &scope);
     QString scope() const;
 
+    /// Workaround needed for Qt 5 not to get confused with types, not necessary on Qt 6
+    void setAnchorsInt(int x) { setAnchors(Anchors(x)); }
+
     /**
      * Gets the LayerShell Window for a given Qt Window
      * Ownership is not transferred
      */
     static Window *get(QWindow *window);
 
+    static Window *qmlAttachedProperties(QObject *object);
+
 Q_SIGNALS:
     void anchorsChanged();
     void exclusionZoneChanged();
@@ -101,7 +114,6 @@ Q_SIGNALS:
     void layerChanged();
 
 private:
-    Window(QWindow *window);
     QScopedPointer<WindowPrivate> d;
 };
 

tests/quicktest.qml

@@ -0,0 +1,115 @@
+/*
+ *   SPDX-FileCopyrightText: 2021 Aleix Pol Gonzalez <aleix.pol_gonzalez@mercedes-benz.com>
+ *
+ *   SPDX-License-Identifier: LGPL-3.0-or-later
+ */
+
+import QtQuick 2.15
+import QtQuick.Window 2.15
+import org.kde.layershell 1.0 as LayerShell
+
+Item
+{
+    Text {
+        text: "A normal Window"
+        anchors.centerIn: parent
+    }
+
+    Window {
+        LayerShell.Window.anchors: LayerShell.Window.AnchorLeft
+        LayerShell.Window.layer: LayerShell.Window.LayerBackground
+        LayerShell.Window.exclusionZone: -1
+
+        Component.onCompleted: {
+            console.log("xxxx", LayerShell.Window.AnchorLeft, LayerShell.Window.anchors)
+        }
+
+        width: 200
+        height: 150
+        Rectangle {
+            anchors.fill: parent
+            color: "green"
+
+            Text {
+                anchors.centerIn: parent
+                text: "left bg"
+            }
+        }
+        visible: true
+    }
+
+
+    Window {
+        LayerShell.Window.scope: "dock"
+        LayerShell.Window.anchors: LayerShell.Window.AnchorLeft
+        LayerShell.Window.layer: LayerShell.Window.LayerTop
+        LayerShell.Window.exclusionZone: width
+
+        width: 100
+        height: 100
+        Rectangle {
+            anchors.fill: parent
+            color: "red"
+
+            Text {
+                anchors.centerIn: parent
+                text: "left"
+            }
+        }
+        visible: true
+    }
+
+    Window {
+        LayerShell.Window.scope: "normal"
+        LayerShell.Window.anchors: LayerShell.Window.AnchorRight
+
+        width: 100
+        height: 100
+        Rectangle {
+            anchors.fill: parent
+            color: "red"
+
+            Text {
+                anchors.centerIn: parent
+                text: "right"
+            }
+        }
+        visible: true
+    }
+
+    Window {
+        LayerShell.Window.scope: "normal"
+        LayerShell.Window.anchors: LayerShell.Window.AnchorTop
+
+        width: 100
+        height: 100
+        Rectangle {
+            anchors.fill: parent
+            color: "red"
+
+            Text {
+                anchors.centerIn: parent
+                text: "top"
+            }
+        }
+        visible: true
+    }
+
+    Window {
+        LayerShell.Window.scope: "normal"
+        LayerShell.Window.anchors: LayerShell.Window.AnchorBottom
+
+        width: 100
+        height: 100
+        Rectangle {
+            anchors.fill: parent
+            color: "red"
+
+            Text {
+                anchors.centerIn: parent
+                text: "bottom"
+            }
+        }
+        visible: true
+    }
+}