Add layoutDirection property to Qt.application element

Task-number: QTBUG-16424
Reviewed-by: Martin Jones

3 files changed, 56 insertions, 2 deletions

diff --git a/src/declarative/util/qdeclarativeapplication.cpp b/src/declarative/util/qdeclarativeapplication.cpp
index 53d196f..f724c16 100644
--- a/src/declarative/util/qdeclarativeapplication.cpp
+++ b/src/declarative/util/qdeclarativeapplication.cpp
@@ -47,8 +47,10 @@ class QDeclarativeApplicationPrivate : public QObjectPrivate
 {
     Q_DECLARE_PUBLIC(QDeclarativeApplication)
 public:
-    QDeclarativeApplicationPrivate() : active(QApplication::activeWindow() != 0) {}
+    QDeclarativeApplicationPrivate() : active(QApplication::activeWindow() != 0),
+    layoutDirection(QApplication::layoutDirection()) {}
     bool active;
+    Qt::LayoutDirection layoutDirection;
 };
 
 /*!
@@ -58,7 +60,8 @@ public:
     \brief The Application element provides access to global application
     state properties shared by many QML components.
 
-    These properties include application activity property \c active.
+    These properties include application activity property \c active,
+    and default layout direction property \c layoutDirection.
 
     \section1 Example Usage
 
@@ -97,6 +100,24 @@ bool QDeclarativeApplication::active() const
     return d->active;
 }
 
+/*!
+    \qmlproperty bool Application::layoutDirection
+
+    This property can be used to query the default layout direction of the
+    application. On system start-up, the default layout direction depends on the
+    application's language. The property has a value Qt.RightToLeft in locales
+    where text and graphic elements are read from right to left, and Qt.LeftToRight
+    where the reading direction flows from left to right. You can bind to the
+    property to customize your application layouts to support both layout
+    directions. This property is readonly.
+
+*/
+bool QDeclarativeApplication::layoutDirection() const
+{
+    Q_D(const QDeclarativeApplication);
+    return d->layoutDirection;
+}
+
 bool QDeclarativeApplication::eventFilter(QObject *obj, QEvent *event)
 {
     Q_UNUSED(obj)
@@ -114,5 +135,12 @@ bool QDeclarativeApplication::eventFilter(QObject *obj, QEvent *event)
             emit activeChanged();
         }
     }
+    if (event->type() == QEvent::LayoutDirectionChange) {
+        Qt::LayoutDirection direction = QApplication::layoutDirection();
+        if (d->layoutDirection != direction) {
+            d->layoutDirection = direction;
+            emit layoutDirectionChanged();
+        }
+    }
     return false;
 }
diff --git a/src/declarative/util/qdeclarativeapplication_p.h b/src/declarative/util/qdeclarativeapplication_p.h
index 59ea7fe..c5cd227 100644
--- a/src/declarative/util/qdeclarativeapplication_p.h
+++ b/src/declarative/util/qdeclarativeapplication_p.h
@@ -57,17 +57,20 @@ class Q_DECLARATIVE_PRIVATE_EXPORT QDeclarativeApplication : public QObject
 {
     Q_OBJECT
     Q_PROPERTY(bool active READ active NOTIFY activeChanged)
+    Q_PROPERTY(bool layoutDirection READ layoutDirection NOTIFY layoutDirectionChanged)
 
 public:
     explicit QDeclarativeApplication(QObject *parent = 0);
     virtual ~QDeclarativeApplication();
     bool active() const;
+    bool layoutDirection() const;
 
 protected:
     bool eventFilter(QObject *obj, QEvent *event);
 
 Q_SIGNALS:
     void activeChanged();
+    void layoutDirectionChanged();
 
 private:
     Q_DISABLE_COPY(QDeclarativeApplication)
diff --git a/tests/auto/declarative/qdeclarativeapplication/tst_qdeclarativeapplication.cpp b/tests/auto/declarative/qdeclarativeapplication/tst_qdeclarativeapplication.cpp
index 0d069dc..3011257 100644
--- a/tests/auto/declarative/qdeclarativeapplication/tst_qdeclarativeapplication.cpp
+++ b/tests/auto/declarative/qdeclarativeapplication/tst_qdeclarativeapplication.cpp
@@ -55,6 +55,7 @@ public:
 
 private slots:
     void active();
+    void layoutDirection();
 
 private:
     QDeclarativeEngine engine;
@@ -91,6 +92,28 @@ void tst_qdeclarativeapplication::active()
     QCOMPARE(item->property("active").toBool(), QApplication::activeWindow() != 0);
 }
 
+void tst_qdeclarativeapplication::layoutDirection()
+{
+    QDeclarativeComponent component(&engine);
+    component.setData("import QtQuick 1.0; Item { property bool layoutDirection: Qt.application.layoutDirection }", QUrl::fromLocalFile(""));
+    QDeclarativeItem *item = qobject_cast<QDeclarativeItem *>(component.create());
+    QVERIFY(item);
+    QGraphicsScene scene;
+    QGraphicsView view(&scene);
+    scene.addItem(item);
+
+    // not mirrored
+    QCOMPARE(Qt::LayoutDirection(item->property("layoutDirection").toInt()), Qt::LeftToRight);
+
+    // mirrored
+    QApplication::setLayoutDirection(Qt::RightToLeft);
+    QCOMPARE(Qt::LayoutDirection(item->property("layoutDirection").toInt()), Qt::RightToLeft);
+
+    // not mirrored again
+    QApplication::setLayoutDirection(Qt::LeftToRight);
+    QCOMPARE(Qt::LayoutDirection(item->property("layoutDirection").toInt()), Qt::LeftToRight);
+}
+
 QTEST_MAIN(tst_qdeclarativeapplication)
 
 #include "tst_qdeclarativeapplication.moc"