Allow resizing Flickable content about a center point.

Useful for zooming via pinch, for example.

Task-number: QTBUG-15148
Reviewed-by: Aaron Kennedy

4 files changed, 139 insertions, 0 deletions

diff --git a/src/declarative/graphicsitems/qdeclarativeflickable.cpp b/src/declarative/graphicsitems/qdeclarativeflickable.cpp
index 377f3b5..b13d82b 100644
--- a/src/declarative/graphicsitems/qdeclarativeflickable.cpp
+++ b/src/declarative/graphicsitems/qdeclarativeflickable.cpp
@@ -1269,6 +1269,60 @@ void QDeclarativeFlickable::setContentHeight(qreal h)
     d->updateBeginningEnd();
 }
 
+/*!
+    \qmlmethod Flickable::resizeContent(real width, real height, QPointF center)
+    \preliminary
+
+    Resizes the content to \a width x \a height about \a center.
+
+    \bold {This method was added in QtQuick 1.1.}
+
+    This does not scale the contents of the Flickable - it only resizes the \l contentWidth
+    and \l contentHeight.
+
+    Resizing the content may result in the content being positioned outside
+    the bounds of the Flickable.  Calling \l returnToBounds() will
+    move the content back within legal bounds.
+*/
+void QDeclarativeFlickable::resizeContent(qreal w, qreal h, QPointF center)
+{
+    Q_D(QDeclarativeFlickable);
+    if (w != d->hData.viewSize) {
+        qreal oldSize = d->hData.viewSize;
+        setContentWidth(w);
+        if (center.x() != 0) {
+            qreal pos = center.x() * w / oldSize;
+            setContentX(contentX() + pos - center.x());
+        }
+    }
+    if (h != d->vData.viewSize) {
+        qreal oldSize = d->vData.viewSize;
+        setContentHeight(h);
+        if (center.y() != 0) {
+            qreal pos = center.y() * h / oldSize;
+            setContentY(contentY() + pos - center.y());
+        }
+    }
+}
+
+/*!
+    \qmlmethod Flickable::returnToBounds()
+    \preliminary
+
+    Ensures the content is within legal bounds.
+
+    \bold {This method was added in QtQuick 1.1.}
+
+    This may be called to ensure that the content is within legal bounds
+    after manually positioning the content.
+*/
+void QDeclarativeFlickable::returnToBounds()
+{
+    Q_D(QDeclarativeFlickable);
+    d->fixupX();
+    d->fixupY();
+}
+
 qreal QDeclarativeFlickable::vWidth() const
 {
     Q_D(const QDeclarativeFlickable);
diff --git a/src/declarative/graphicsitems/qdeclarativeflickable_p.h b/src/declarative/graphicsitems/qdeclarativeflickable_p.h
index 6e4d8ed..ece2db7 100644
--- a/src/declarative/graphicsitems/qdeclarativeflickable_p.h
+++ b/src/declarative/graphicsitems/qdeclarativeflickable_p.h
@@ -149,6 +149,10 @@ public:
     FlickableDirection flickableDirection() const;
     void setFlickableDirection(FlickableDirection);
 
+    //XXX Added in QtQuick 1.1
+    Q_INVOKABLE void resizeContent(qreal w, qreal h, QPointF center);
+    Q_INVOKABLE void returnToBounds();
+
 Q_SIGNALS:
     void contentWidthChanged();
     void contentHeightChanged();
diff --git a/tests/auto/declarative/qdeclarativeflickable/data/resize.qml b/tests/auto/declarative/qdeclarativeflickable/data/resize.qml
new file mode 100644
index 0000000..e2abb99
--- /dev/null
+++ b/tests/auto/declarative/qdeclarativeflickable/data/resize.qml
@@ -0,0 +1,27 @@
+import QtQuick 1.1
+
+Rectangle {
+    function resizeContent() {
+        flick.resizeContent(600, 600, Qt.point(100, 100))
+    }
+    function returnToBounds() {
+        flick.returnToBounds()
+    }
+    width: 400
+    height: 360
+    color: "gray"
+
+    Flickable {
+        id: flick
+        objectName: "flick"
+        anchors.fill: parent
+        contentWidth: 300
+        contentHeight: 300
+
+        Rectangle {
+            width: flick.contentWidth
+            height: flick.contentHeight
+            color: "red"
+        }
+    }
+}
diff --git a/tests/auto/declarative/qdeclarativeflickable/tst_qdeclarativeflickable.cpp b/tests/auto/declarative/qdeclarativeflickable/tst_qdeclarativeflickable.cpp
index 25edb36..c1564bc 100644
--- a/tests/auto/declarative/qdeclarativeflickable/tst_qdeclarativeflickable.cpp
+++ b/tests/auto/declarative/qdeclarativeflickable/tst_qdeclarativeflickable.cpp
@@ -46,6 +46,7 @@
 #include <private/qdeclarativevaluetype_p.h>
 #include <QtGui/qgraphicswidget.h>
 #include <math.h>
+#include "../../../shared/util.h"
 
 #ifdef Q_OS_SYMBIAN
 // In Symbian OS test data is located in applications private dir
@@ -69,6 +70,8 @@ private slots:
     void pressDelay();
     void flickableDirection();
     void qgraphicswidget();
+    void resizeContent();
+    void returnToBounds();
 
 private:
     QDeclarativeEngine engine;
@@ -277,6 +280,57 @@ void tst_qdeclarativeflickable::qgraphicswidget()
     QVERIFY(widget);
 }
 
+// QtQuick 1.1
+void tst_qdeclarativeflickable::resizeContent()
+{
+    QDeclarativeEngine engine;
+    QDeclarativeComponent c(&engine, QUrl::fromLocalFile(SRCDIR "/data/resize.qml"));
+    QDeclarativeItem *root = qobject_cast<QDeclarativeItem*>(c.create());
+    QDeclarativeFlickable *obj = findItem<QDeclarativeFlickable>(root, "flick");
+
+    QVERIFY(obj != 0);
+    QCOMPARE(obj->contentX(), 0.);
+    QCOMPARE(obj->contentY(), 0.);
+    QCOMPARE(obj->contentWidth(), 300.);
+    QCOMPARE(obj->contentHeight(), 300.);
+
+    QMetaObject::invokeMethod(root, "resizeContent");
+
+    QCOMPARE(obj->contentX(), 100.);
+    QCOMPARE(obj->contentY(), 100.);
+    QCOMPARE(obj->contentWidth(), 600.);
+    QCOMPARE(obj->contentHeight(), 600.);
+
+    delete root;
+}
+
+// QtQuick 1.1
+void tst_qdeclarativeflickable::returnToBounds()
+{
+    QDeclarativeEngine engine;
+    QDeclarativeComponent c(&engine, QUrl::fromLocalFile(SRCDIR "/data/resize.qml"));
+    QDeclarativeItem *root = qobject_cast<QDeclarativeItem*>(c.create());
+    QDeclarativeFlickable *obj = findItem<QDeclarativeFlickable>(root, "flick");
+
+    QVERIFY(obj != 0);
+    QCOMPARE(obj->contentX(), 0.);
+    QCOMPARE(obj->contentY(), 0.);
+    QCOMPARE(obj->contentWidth(), 300.);
+    QCOMPARE(obj->contentHeight(), 300.);
+
+    obj->setContentX(100);
+    obj->setContentY(400);
+    QTRY_COMPARE(obj->contentX(), 100.);
+    QTRY_COMPARE(obj->contentY(), 400.);
+
+    QMetaObject::invokeMethod(root, "returnToBounds");
+
+    QTRY_COMPARE(obj->contentX(), 0.);
+    QTRY_COMPARE(obj->contentY(), 0.);
+
+    delete root;
+}
+
 template<typename T>
 T *tst_qdeclarativeflickable::findItem(QGraphicsObject *parent, const QString &objectName)
 {