Add a ScreenEdgeItem to reserve a screen edge from QML

Usage:
ScreenEdgeItem {
    edge: ScreenEdgeItem.LeftEdge
    onActivated: doSomething()
}

CMakeLists.txt

@@ -156,6 +156,7 @@ if(KWIN_BUILD_SCRIPTING)
         scripting/timer.cpp
         scripting/scripting_model.cpp
         scripting/dbuscall.cpp
+        scripting/screenedgeitem.cpp
     )
 endif()
 

scripting/screenedgeitem.cpp

@@ -0,0 +1,91 @@
+/********************************************************************
+ KWin - the KDE window manager
+ This file is part of the KDE project.
+
+Copyright (C) 2013 Martin Gräßlin <mgraesslin@kde.org>
+
+This program is free software; you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation; either version 2 of the License, or
+(at your option) any later version.
+
+This program is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with this program.  If not, see <http://www.gnu.org/licenses/>.
+*********************************************************************/
+#include "screenedgeitem.h"
+#include <config-kwin.h>
+#ifdef KWIN_BUILD_SCREENEDGES
+#include "screenedge.h"
+#endif
+
+namespace KWin
+{
+
+ScreenEdgeItem::ScreenEdgeItem(QObject* parent)
+    : QObject(parent)
+    , m_enabled(true)
+    , m_edge(NoEdge)
+{
+}
+
+ScreenEdgeItem::~ScreenEdgeItem()
+{
+}
+
+void ScreenEdgeItem::setEnabled(bool enabled)
+{
+    if (m_enabled == enabled) {
+        return;
+    }
+    disableEdge();
+    m_enabled = enabled;
+    enableEdge();
+    emit enabledChanged();
+}
+
+void ScreenEdgeItem::setEdge(Edge edge)
+{
+    if (m_edge == edge) {
+        return;
+    }
+    disableEdge();
+    m_edge = edge;
+    enableEdge();
+    emit edgeChanged();
+}
+
+void ScreenEdgeItem::enableEdge()
+{
+    if (!m_enabled || m_edge == NoEdge) {
+        return;
+    }
+#ifdef KWIN_BUILD_SCREENEDGES
+    ScreenEdges::self()->reserve(static_cast<ElectricBorder>(m_edge), this, "borderActivated");
+#endif
+}
+
+void ScreenEdgeItem::disableEdge()
+{
+    if (!m_enabled || m_edge == NoEdge) {
+        return;
+    }
+#ifdef KWIN_BUILD_SCREENEDGES
+    ScreenEdges::self()->unreserve(static_cast<ElectricBorder>(m_edge), this);
+#endif
+}
+
+bool ScreenEdgeItem::borderActivated(ElectricBorder edge)
+{
+    if (edge != static_cast<ElectricBorder>(m_edge) || !m_enabled) {
+        return false;
+    }
+    emit activated();
+    return true;
+}
+
+} // namespace

scripting/screenedgeitem.h

@@ -0,0 +1,108 @@
+/********************************************************************
+ KWin - the KDE window manager
+ This file is part of the KDE project.
+
+Copyright (C) 2013 Martin Gräßlin <mgraesslin@kde.org>
+
+This program is free software; you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation; either version 2 of the License, or
+(at your option) any later version.
+
+This program is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with this program.  If not, see <http://www.gnu.org/licenses/>.
+*********************************************************************/
+#ifndef KWIN_SCREENEDGEITEM_H
+#define KWIN_SCREENEDGEITEM_H
+
+#include <QObject>
+#include <kwinglobals.h>
+
+namespace KWin
+{
+
+/**
+ * @brief Qml export for reserving a Screen Edge.
+ *
+ * The edge is controlled by the @c enabled property and the @c edge
+ * property. If the edge is enabled and gets triggered the @link activated()
+ * signal gets emitted.
+ *
+ * Example usage:
+ * @code
+ * ScreenEdgeItem {
+ *     edge: ScreenEdgeItem.LeftEdge
+ *     onActivated: doSomething()
+ * }
+ * @endcode
+ *
+ */
+class ScreenEdgeItem : public QObject
+{
+    Q_OBJECT
+    Q_ENUMS(Edge)
+    /**
+     * @brief Whether the edge is currently enabled, that is reserved. Default value is @c true.
+     *
+     */
+    Q_PROPERTY(bool enabled READ isEnabled WRITE setEnabled NOTIFY enabledChanged)
+    /**
+     * @brief Which of the screen edges is to be reserved. Default value is @c NoEdge.
+     *
+     */
+    Q_PROPERTY(Edge edge READ edge WRITE setEdge NOTIFY edgeChanged)
+public:
+    enum Edge {
+        TopEdge,
+        TopRightEdge,
+        RightEdge,
+        BottomRightEdge,
+        BottomEdge,
+        BottomLeftEdge,
+        LeftEdge,
+        TopLeftEdge,
+        EDGE_COUNT,
+        NoEdge
+    };
+    explicit ScreenEdgeItem(QObject *parent = 0);
+    virtual ~ScreenEdgeItem();
+    bool isEnabled() const;
+    Edge edge() const;
+
+public Q_SLOTS:
+    void setEnabled(bool enabled);
+    void setEdge(Edge edge);
+
+Q_SIGNALS:
+    void enabledChanged();
+    void edgeChanged();
+
+    void activated();
+
+private Q_SLOTS:
+    bool borderActivated(ElectricBorder edge);
+private:
+    void enableEdge();
+    void disableEdge();
+    bool m_enabled;
+    Edge m_edge;
+};
+
+inline bool ScreenEdgeItem::isEnabled() const
+{
+    return m_enabled;
+}
+
+inline ScreenEdgeItem::Edge ScreenEdgeItem::edge() const
+{
+    return m_edge;
+}
+
+} // namespace KWin
+
+#endif //  KWIN_SCREENEDGEITEM_H

scripting/scripting.cpp

@@ -25,6 +25,7 @@ along with this program.  If not, see <http://www.gnu.org/licenses/>.
 #include "meta.h"
 #include "scriptingutils.h"
 #include "workspace_wrapper.h"
+#include "screenedgeitem.h"
 #include "scripting_model.h"
 #include "../client.h"
 #include "../thumbnailitem.h"
@@ -549,6 +550,7 @@ void KWin::DeclarativeScript::run()
     qmlRegisterType<DesktopThumbnailItem>("org.kde.kwin", 2, 0, "DesktopThumbnailItem");
     qmlRegisterType<WindowThumbnailItem>("org.kde.kwin", 2, 0, "ThumbnailItem");
     qmlRegisterType<DBusCall>("org.kde.kwin", 2, 0, "DBusCall");
+    qmlRegisterType<ScreenEdgeItem>("org.kde.kwin", 2, 0, "ScreenEdgeItem");
     qmlRegisterType<KWin::ScriptingClientModel::ClientModel>();
     qmlRegisterType<KWin::ScriptingClientModel::SimpleClientModel>("org.kde.kwin", 2, 0, "ClientModel");
     qmlRegisterType<KWin::ScriptingClientModel::ClientModelByScreen>("org.kde.kwin", 2, 0, "ClientModelByScreen");