Add mapFromItem() and mapToItem() in QDeclarativeItem.

Task-number: QT-2385

4 files changed, 158 insertions, 0 deletions

diff --git a/src/declarative/graphicsitems/qdeclarativeitem.cpp b/src/declarative/graphicsitems/qdeclarativeitem.cpp
index 5014fd8..cb3f542 100644
--- a/src/declarative/graphicsitems/qdeclarativeitem.cpp
+++ b/src/declarative/graphicsitems/qdeclarativeitem.cpp
@@ -43,6 +43,7 @@
 #include "qdeclarativeitem.h"
 
 #include "qdeclarativeevents_p_p.h"
+#include <private/qdeclarativeengine_p.h>
 
 #include <qfxperf_p_p.h>
 #include <qdeclarativeengine.h>
@@ -51,6 +52,7 @@
 #include <qdeclarativeview.h>
 #include <qdeclarativestategroup_p.h>
 #include <qdeclarativecomponent.h>
+#include <qdeclarativeinfo.h>
 
 #include <QDebug>
 #include <QPen>
@@ -2162,6 +2164,58 @@ void QDeclarativeItem::setKeepMouseGrab(bool keep)
 }
 
 /*!
+    \qmlmethod object Item::mapFromItem(Item item, int x, int y)
+
+    Maps the point (\a x, \a y), which is in \a item's coordinate system, to
+    this item's coordinate system, and returns an object with \c x and \c y 
+    properties matching the mapped cooordinate.
+
+    If \a item is a \c null value, this maps the point from the coordinate
+    system of the root QML view.
+*/
+QScriptValue QDeclarativeItem::mapFromItem(const QScriptValue &item, int x, int y) const
+{
+    QScriptValue sv = QDeclarativeEnginePrivate::getScriptEngine(qmlEngine(this))->newObject();
+    QDeclarativeItem *itemObj = qobject_cast<QDeclarativeItem*>(item.toQObject());
+    if (!itemObj && !item.isNull()) {
+        qWarning().nospace() << "mapFromItem() given argument " << item.toString() << " which is neither null nor an Item";
+        return 0;
+    }
+
+    // If QGraphicsItem::mapFromItem() is called with 0, behaves the same as mapFromScene()
+    QPointF p = qobject_cast<QGraphicsItem*>(this)->mapFromItem(itemObj, x, y);
+    sv.setProperty("x", p.x());
+    sv.setProperty("y", p.y());
+    return sv;
+}
+
+/*!
+    \qmlmethod object Item::mapToItem(Item item, int x, int y)
+
+    Maps the point (\a x, \a y), which is in this item's coordinate system, to
+    \a item's coordinate system, and returns an object with \c x and \c y
+    properties matching the mapped cooordinate.
+
+    If \a item is a \c null value, this maps \a x and \a y to the coordinate
+    system of the root QML view.
+*/
+QScriptValue QDeclarativeItem::mapToItem(const QScriptValue &item, int x, int y) const
+{
+    QScriptValue sv = QDeclarativeEnginePrivate::getScriptEngine(qmlEngine(this))->newObject();
+    QDeclarativeItem *itemObj = qobject_cast<QDeclarativeItem*>(item.toQObject());
+    if (!itemObj && !item.isNull()) {
+        qWarning().nospace() << "mapToItem() given argument " << item.toString() << " which is neither null nor an Item";
+        return 0;
+    }
+
+    // If QGraphicsItem::mapToItem() is called with 0, behaves the same as mapToScene()
+    QPointF p = qobject_cast<QGraphicsItem*>(this)->mapToItem(itemObj, x, y);
+    sv.setProperty("x", p.x());
+    sv.setProperty("y", p.y());
+    return sv;
+}
+
+/*!
   \internal
 
   This function emits the \e focusChanged signal.
diff --git a/src/declarative/graphicsitems/qdeclarativeitem.h b/src/declarative/graphicsitems/qdeclarativeitem.h
index 3ae404d..f6fedc7 100644
--- a/src/declarative/graphicsitems/qdeclarativeitem.h
+++ b/src/declarative/graphicsitems/qdeclarativeitem.h
@@ -159,6 +159,9 @@ public:
     bool keepMouseGrab() const;
     void setKeepMouseGrab(bool);
 
+    Q_INVOKABLE QScriptValue mapFromItem(const QScriptValue &item, int x, int y) const;
+    Q_INVOKABLE QScriptValue mapToItem(const QScriptValue &item, int x, int y) const;
+
     QDeclarativeAnchorLine left() const;
     QDeclarativeAnchorLine right() const;
     QDeclarativeAnchorLine horizontalCenter() const;
diff --git a/tests/auto/declarative/qdeclarativeitem/data/mapCoordinates.qml b/tests/auto/declarative/qdeclarativeitem/data/mapCoordinates.qml
new file mode 100644
index 0000000..40a2106
--- /dev/null
+++ b/tests/auto/declarative/qdeclarativeitem/data/mapCoordinates.qml
@@ -0,0 +1,43 @@
+import Qt 4.6
+
+Item {
+    id: root; objectName: "root"
+    width: 200; height: 200
+
+    Item { id: itemA; objectName: "itemA"; x: 50; y: 50 }
+
+    Item {
+        x: 50; y: 50
+        Item { id: itemB; objectName: "itemB"; x: 100; y: 100 }
+    }
+
+    function mapAToB(x, y) {
+        var pos = itemA.mapToItem(itemB, x, y)
+        return Qt.point(pos.x, pos.y)
+    }
+
+    function mapAFromB(x, y) {
+        var pos = itemA.mapFromItem(itemB, x, y)
+        return Qt.point(pos.x, pos.y)
+    }
+
+    function mapAToNull(x, y) {
+        var pos = itemA.mapToItem(null, x, y)
+        return Qt.point(pos.x, pos.y)
+    }
+
+    function mapAFromNull(x, y) {
+        var pos = itemA.mapFromItem(null, x, y)
+        return Qt.point(pos.x, pos.y)
+    }
+
+    function checkMapAToInvalid(x, y) {
+        var pos = itemA.mapToItem(1122, x, y)
+        return pos.x == undefined && pos.y == undefined
+    }
+
+    function checkMapAFromInvalid(x, y) {
+        var pos = itemA.mapFromItem(1122, x, y)
+        return pos.x == undefined && pos.y == undefined
+    }
+}
diff --git a/tests/auto/declarative/qdeclarativeitem/tst_qdeclarativeitem.cpp b/tests/auto/declarative/qdeclarativeitem/tst_qdeclarativeitem.cpp
index 36dcf1f..3e69db9 100644
--- a/tests/auto/declarative/qdeclarativeitem/tst_qdeclarativeitem.cpp
+++ b/tests/auto/declarative/qdeclarativeitem/tst_qdeclarativeitem.cpp
@@ -58,6 +58,8 @@ private slots:
     void keyNavigation();
     void smooth();
     void clip();
+    void mapCoordinates();
+    void mapCoordinates_data();
 
 private:
     template<typename T>
@@ -288,6 +290,62 @@ void tst_QDeclarativeItem::clip()
     QCOMPARE(spy.count(),2);
 }
 
+void tst_QDeclarativeItem::mapCoordinates()
+{
+    QFETCH(int, x);
+    QFETCH(int, y);
+
+    QDeclarativeView *canvas = new QDeclarativeView(0);
+    canvas->setFixedSize(300, 300);
+    canvas->setSource(QUrl::fromLocalFile(SRCDIR "/data/mapCoordinates.qml"));
+    canvas->show();
+    qApp->processEvents();
+
+    QDeclarativeItem *root = qobject_cast<QDeclarativeItem*>(canvas->rootObject());
+    QVERIFY(root != 0);
+    QDeclarativeItem *a = findItem<QDeclarativeItem>(canvas->rootObject(), "itemA");
+    QVERIFY(a != 0);
+    QDeclarativeItem *b = findItem<QDeclarativeItem>(canvas->rootObject(), "itemB");
+    QVERIFY(b != 0);
+
+    QVariant result;
+
+    QVERIFY(QMetaObject::invokeMethod(root, "mapAToB",
+            Q_RETURN_ARG(QVariant, result), Q_ARG(QVariant, x), Q_ARG(QVariant, y)));
+    QCOMPARE(result.value<QPointF>(), qobject_cast<QGraphicsItem*>(a)->mapToItem(b, x, y));
+
+    QVERIFY(QMetaObject::invokeMethod(root, "mapAFromB",
+            Q_RETURN_ARG(QVariant, result), Q_ARG(QVariant, x), Q_ARG(QVariant, y)));
+    QCOMPARE(result.value<QPointF>(), qobject_cast<QGraphicsItem*>(a)->mapFromItem(b, x, y));
+
+    QVERIFY(QMetaObject::invokeMethod(root, "mapAToNull",
+            Q_RETURN_ARG(QVariant, result), Q_ARG(QVariant, x), Q_ARG(QVariant, y)));
+    QCOMPARE(result.value<QPointF>(), qobject_cast<QGraphicsItem*>(a)->mapToScene(x, y));
+
+    QVERIFY(QMetaObject::invokeMethod(root, "mapAFromNull",
+            Q_RETURN_ARG(QVariant, result), Q_ARG(QVariant, x), Q_ARG(QVariant, y)));
+    QCOMPARE(result.value<QPointF>(), qobject_cast<QGraphicsItem*>(a)->mapFromScene(x, y));
+
+    QTest::ignoreMessage(QtWarningMsg, "mapToItem() given argument \"1122\" which is neither null nor an Item");
+    QVERIFY(QMetaObject::invokeMethod(root, "checkMapAToInvalid",
+            Q_RETURN_ARG(QVariant, result), Q_ARG(QVariant, x), Q_ARG(QVariant, y)));
+    QVERIFY(result.toBool());
+
+    QTest::ignoreMessage(QtWarningMsg, "mapFromItem() given argument \"1122\" which is neither null nor an Item");
+    QVERIFY(QMetaObject::invokeMethod(root, "checkMapAFromInvalid",
+            Q_RETURN_ARG(QVariant, result), Q_ARG(QVariant, x), Q_ARG(QVariant, y)));
+    QVERIFY(result.toBool());
+}
+
+void tst_QDeclarativeItem::mapCoordinates_data()
+{
+    QTest::addColumn<int>("x");
+    QTest::addColumn<int>("y");
+
+    for (int i=-20; i<=20; i+=10)
+        QTest::newRow(QTest::toString(i)) << i << i;
+}
+
 template<typename T>
 T *tst_QDeclarativeItem::findItem(QGraphicsObject *parent, const QString &objectName)
 {