Add Screen attached object

Use this to get details of the screen such as size and current
orientation.

As well as adding its own example, this commit updates Calculator to
use Screen instead of Runtime for orientation.

Change-Id: I1b73d2ee22a92b1dee827de1bd893eebec9f5817
Reviewed-by: Michael Brasser <michael.brasser@nokia.com>

6 files changed, 292 insertions, 0 deletions

diff --git a/src/quick/items/items.pri b/src/quick/items/items.pri
index a224db31d6..8a581920ea 100644
--- a/src/quick/items/items.pri
+++ b/src/quick/items/items.pri
@@ -67,6 +67,7 @@ HEADERS += \
     $$PWD/qquickmultipointtoucharea_p.h \
     $$PWD/qquickitemview_p.h \
     $$PWD/qquickitemview_p_p.h \
+    $$PWD/qquickscreen_p.h \
     $$PWD/qquickwindowmodule_p.h \
     $$PWD/qquickwindowmanager_p.h
 
@@ -116,6 +117,7 @@ SOURCES += \
     $$PWD/qquickmultipointtoucharea.cpp \
     $$PWD/qquickitemview.cpp \
     $$PWD/qquickwindowmodule.cpp \
+    $$PWD/qquickscreen.cpp \
     $$PWD/qquickwindowmanager.cpp
 
 SOURCES += \
diff --git a/src/quick/items/qquickitem.cpp b/src/quick/items/qquickitem.cpp
index 5ec0787d9e..8f58c33613 100644
--- a/src/quick/items/qquickitem.cpp
+++ b/src/quick/items/qquickitem.cpp
@@ -46,6 +46,7 @@
 #include "qquickcanvas_p.h"
 
 #include "qquickevents_p_p.h"
+#include "qquickscreen_p.h"
 
 #include <QtDeclarative/qdeclarativeengine.h>
 #include <QtDeclarative/qdeclarativecomponent.h>
@@ -2136,6 +2137,8 @@ void QQuickItemPrivate::initCanvas(InitializationState *state, QQuickCanvas *c)
 
     dirty(Canvas);
 
+    if (screenAttached)
+        screenAttached->canvasChanged(c);
     itemChange(QQuickItem::ItemSceneChange, c);
 }
 
@@ -2264,6 +2267,7 @@ QQuickItemPrivate::QQuickItemPrivate()
 
   itemNodeInstance(0), opacityNode(0), clipNode(0), rootNode(0), groupNode(0), paintNode(0)
   , beforePaintNode(0), effectRefCount(0), hideRefCount(0)
+  , screenAttached(0)
 {
 }
 
diff --git a/src/quick/items/qquickitem_p.h b/src/quick/items/qquickitem_p.h
index 79d98d7fe4..e9c9498c44 100644
--- a/src/quick/items/qquickitem_p.h
+++ b/src/quick/items/qquickitem_p.h
@@ -83,6 +83,7 @@ QT_BEGIN_NAMESPACE
 class QNetworkReply;
 class QQuickItemKeyFilter;
 class QQuickLayoutMirroringAttached;
+class QQuickScreenAttached;
 
 class QQuickContents : public QQuickItemChangeListener
 {
@@ -445,6 +446,8 @@ public:
 
     virtual void mirrorChange() {}
 
+    QQuickScreenAttached *screenAttached;
+
     static qint64 consistentTime;
     static void setConsistentTime(qint64 t);
     static void start(QElapsedTimer &);
diff --git a/src/quick/items/qquickscreen.cpp b/src/quick/items/qquickscreen.cpp
new file mode 100644
index 0000000000..b1b4ff1d8c
--- /dev/null
+++ b/src/quick/items/qquickscreen.cpp
@@ -0,0 +1,176 @@
+/****************************************************************************
+**
+** Copyright (C) 2011 Nokia Corporation and/or its subsidiary(-ies).
+** All rights reserved.
+** Contact: Nokia Corporation (qt-info@nokia.com)
+**
+** This file is part of the QtDeclarative module of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** GNU Lesser General Public License Usage
+** This file may be used under the terms of the GNU Lesser General Public
+** License version 2.1 as published by the Free Software Foundation and
+** appearing in the file LICENSE.LGPL included in the packaging of this
+** file. Please review the following information to ensure the GNU Lesser
+** General Public License version 2.1 requirements will be met:
+** http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
+**
+** In addition, as a special exception, Nokia gives you certain additional
+** rights. These rights are described in the Nokia Qt LGPL Exception
+** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU General
+** Public License version 3.0 as published by the Free Software Foundation
+** and appearing in the file LICENSE.GPL included in the packaging of this
+** file. Please review the following information to ensure the GNU General
+** Public License version 3.0 requirements will be met:
+** http://www.gnu.org/copyleft/gpl.html.
+**
+** Other Usage
+** Alternatively, this file may be used in accordance with the terms and
+** conditions contained in a signed written agreement between you and Nokia.
+**
+**
+**
+**
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#include "qquickscreen_p.h"
+
+#include "qquickitem.h"
+#include "qquickitem_p.h"
+#include "qquickcanvas.h"
+
+#include <QScreen>
+
+QT_BEGIN_NAMESPACE
+
+/*!
+    \qmlclass Screen QQuickScreenAttached
+    \inqmlmodule QtQuick.Window 2
+    \brief The Screen attached object provides information about the Screen an Item is displayed on.
+
+    The Screen attached object is only valid inside Item or Item derived elements. Inside these elements
+    it refers to the screen that the element is currently being displayed on.
+*/
+
+/*!
+    \qmlattachedproperty int QtQuickWindow2::Screen::width
+    \readonly
+
+    This contains the width of the screen in pixels.
+*/
+/*!
+    \qmlattachedproperty int QtQuickWindow2::Screen::height
+    \readonly
+
+    This contains the height of the screen in pixels.
+*/
+/*!
+    \qmlattachedproperty Qt::ScreenOrientation QtQuickWindow2::Screen::primaryOrientation
+    \readonly
+
+    This contains the primary orientation of the screen. This can only change if the screen changes.
+*/
+/*!
+    \qmlattachedproperty Qt::ScreenOrientation QtQuickWindow2::Screen::currentOrientation
+    \readonly
+
+    This contains the current orientation of the screen.
+*/
+/*!
+    \qmlattachedmethod int QtQuickWindow2::Screen::angleBetween(Qt::ScreenOrientation a, Qt::ScreenOrientation b)
+
+    Returns the rotation angle, in degrees, between the two specified angles.
+*/
+
+QQuickScreenAttached::QQuickScreenAttached(QObject* attachee)
+    : QObject(attachee)
+    , m_screen(0)
+{
+    m_attachee = qobject_cast<QQuickItem*>(attachee);
+
+    if (m_attachee) {
+        QQuickItemPrivate::get(m_attachee)->screenAttached = this;
+
+        if (m_attachee->canvas()) //It might not be assigned to a canvas yet
+            canvasChanged(m_attachee->canvas());
+    }
+}
+
+int QQuickScreenAttached::width() const
+{
+    if (!m_screen)
+        return 0;
+    return m_screen->size().width();
+}
+
+int QQuickScreenAttached::height() const
+{
+    if (!m_screen)
+        return 0;
+    return m_screen->size().height();
+}
+
+Qt::ScreenOrientation QQuickScreenAttached::primaryOrientation() const
+{
+    if (!m_screen)
+        return Qt::UnknownOrientation;
+    return m_screen->primaryOrientation();
+}
+
+Qt::ScreenOrientation QQuickScreenAttached::currentOrientation() const
+{
+    if (!m_screen)
+        return Qt::UnknownOrientation;
+    return m_screen->currentOrientation();
+}
+
+int QQuickScreenAttached::angleBetween(Qt::ScreenOrientation a, Qt::ScreenOrientation b)
+{
+    return QScreen::angleBetween(a,b);
+}
+
+void QQuickScreenAttached::canvasChanged(QQuickCanvas* c)//Called by QQuickItemPrivate::initCanvas
+{
+    QScreen* screen = c ? c->screen() : 0;
+    if (screen != m_screen) {
+        QScreen* oldScreen = m_screen;
+        m_screen = screen;
+
+        if (oldScreen) {
+            disconnect(oldScreen, SIGNAL(sizeChanged(QSize)),
+                    this, SIGNAL(widthChanged()));
+            disconnect(oldScreen, SIGNAL(sizeChanged(QSize)),
+                    this, SIGNAL(heightChanged()));
+            disconnect(oldScreen, SIGNAL(currentOrientationChanged(Qt::ScreenOrientation)),
+                    this, SIGNAL(currentOrientationChanged()));
+        }
+
+        if (!screen)
+            return; //Don't bother emitting signals, because the new values are garbage anyways
+
+        if (!oldScreen || screen->size() != oldScreen->size()) {
+            emit widthChanged();
+            emit heightChanged();
+        }
+        if (!oldScreen || screen->currentOrientation() != oldScreen->currentOrientation())
+            emit currentOrientationChanged();
+        if (!oldScreen || screen->primaryOrientation() != oldScreen->primaryOrientation())
+            emit primaryOrientationChanged();
+
+
+        connect(screen, SIGNAL(sizeChanged(QSize)),
+                this, SIGNAL(widthChanged()));
+        connect(screen, SIGNAL(sizeChanged(QSize)),
+                this, SIGNAL(heightChanged()));
+        connect(screen, SIGNAL(currentOrientationChanged(Qt::ScreenOrientation)),
+                this, SIGNAL(currentOrientationChanged()));
+    }
+}
+
+QT_END_NAMESPACE
diff --git a/src/quick/items/qquickscreen_p.h b/src/quick/items/qquickscreen_p.h
new file mode 100644
index 0000000000..6c1567ba72
--- /dev/null
+++ b/src/quick/items/qquickscreen_p.h
@@ -0,0 +1,105 @@
+/****************************************************************************
+**
+** Copyright (C) 2011 Nokia Corporation and/or its subsidiary(-ies).
+** All rights reserved.
+** Contact: Nokia Corporation (qt-info@nokia.com)
+**
+** This file is part of the QtDeclarative module of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** GNU Lesser General Public License Usage
+** This file may be used under the terms of the GNU Lesser General Public
+** License version 2.1 as published by the Free Software Foundation and
+** appearing in the file LICENSE.LGPL included in the packaging of this
+** file. Please review the following information to ensure the GNU Lesser
+** General Public License version 2.1 requirements will be met:
+** http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
+**
+** In addition, as a special exception, Nokia gives you certain additional
+** rights. These rights are described in the Nokia Qt LGPL Exception
+** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU General
+** Public License version 3.0 as published by the Free Software Foundation
+** and appearing in the file LICENSE.GPL included in the packaging of this
+** file. Please review the following information to ensure the GNU General
+** Public License version 3.0 requirements will be met:
+** http://www.gnu.org/copyleft/gpl.html.
+**
+** Other Usage
+** Alternatively, this file may be used in accordance with the terms and
+** conditions contained in a signed written agreement between you and Nokia.
+**
+**
+**
+**
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#ifndef QQUICKSCREEN_P_H
+#define QQUICKSCREEN_P_H
+
+#include <qdeclarative.h>
+#include <QRect>
+#include <QSize>
+#include <private/qdeclarativeglobal_p.h>
+
+QT_BEGIN_HEADER
+
+QT_BEGIN_NAMESPACE
+
+QT_MODULE(Declarative)
+
+class QQuickItem;
+class QQuickCanvas;
+class QScreen;
+
+class Q_AUTOTEST_EXPORT QQuickScreenAttached : public QObject
+{
+    Q_OBJECT
+
+    Q_PROPERTY(int width READ width NOTIFY widthChanged)
+    Q_PROPERTY(int height READ height NOTIFY heightChanged)
+    Q_PROPERTY(Qt::ScreenOrientation primaryOrientation READ primaryOrientation NOTIFY primaryOrientationChanged)
+    Q_PROPERTY(Qt::ScreenOrientation currentOrientation READ currentOrientation NOTIFY currentOrientationChanged)
+
+public:
+    QQuickScreenAttached(QObject* attachee);
+
+    int width() const;
+    int height() const;
+    Qt::ScreenOrientation primaryOrientation() const;
+    Qt::ScreenOrientation currentOrientation() const;
+
+    Q_INVOKABLE int angleBetween(Qt::ScreenOrientation a, Qt::ScreenOrientation b);
+
+    void canvasChanged(QQuickCanvas*);
+
+Q_SIGNALS:
+    void widthChanged();
+    void heightChanged();
+    void primaryOrientationChanged();
+    void currentOrientationChanged();
+
+private:
+    QScreen* m_screen;
+    QQuickItem* m_attachee;
+};
+
+class Q_AUTOTEST_EXPORT QQuickScreen : public QObject
+{
+    Q_OBJECT
+public:
+    static QQuickScreenAttached *qmlAttachedProperties(QObject *object){ return new QQuickScreenAttached(object); }
+};
+
+QT_END_NAMESPACE
+
+QML_DECLARE_TYPEINFO(QQuickScreen, QML_HAS_ATTACHED_PROPERTIES)
+
+QT_END_HEADER
+
+#endif
diff --git a/src/quick/items/qquickwindowmodule.cpp b/src/quick/items/qquickwindowmodule.cpp
index 726ea055d8..23ca00dd0a 100644
--- a/src/quick/items/qquickwindowmodule.cpp
+++ b/src/quick/items/qquickwindowmodule.cpp
@@ -40,6 +40,7 @@
 ****************************************************************************/
 
 #include "qquickwindowmodule_p.h"
+#include "qquickscreen_p.h"
 #include <QtQuick/QQuickCanvas>
 
 QT_BEGIN_NAMESPACE
@@ -49,6 +50,7 @@ void QQuickWindowModule::defineModule()
     const char* uri = "QtQuick.Window";
 
     qmlRegisterType<QQuickCanvas>(uri, 2, 0, "Window");
+    qmlRegisterUncreatableType<QQuickScreen>(uri, 2, 0, "Screen", "Screen can only be used via the attached property.");
 }
 
 QT_END_NAMESPACE