4 files changed, 126 insertions, 0 deletions

diff --git a/src/controls/Private/ScrollViewHelper.qml b/src/controls/Private/ScrollViewHelper.qml
index b4a589bf..bc3d9eb8 100644
--- a/src/controls/Private/ScrollViewHelper.qml
+++ b/src/controls/Private/ScrollViewHelper.qml
@@ -131,6 +131,11 @@ Item {
         anchors.right: cornerFill.left
         anchors.leftMargin:  leftMargin
         anchors.bottomMargin: bottomMargin
+        onScrollAmountChanged: {
+            if (flickableItem && (flickableItem.atXBeginning || flickableItem.atXEnd)) {
+                value = flickableItem.contentX - flickableItem.originX
+            }
+        }
         onValueChanged: {
             if (!blockUpdates) {
                 flickableItem.contentX = value + flickableItem.originX
@@ -180,6 +185,11 @@ Item {
         anchors.top: parent.top
         anchors.topMargin: __scrollBarTopMargin + topMargin
         anchors.rightMargin: rightMargin
+        onScrollAmountChanged: {
+            if (flickableItem && (flickableItem.atYBeginning || flickableItem.atYEnd)) {
+                value = flickableItem.contentY - flickableItem.originY
+            }
+        }
         onValueChanged: {
             if (flickableItem && !blockUpdates && enabled) {
                 flickableItem.contentY = value + flickableItem.originY
diff --git a/tests/auto/controls/data/tst_scrollview.qml b/tests/auto/controls/data/tst_scrollview.qml
index e687c9bc..cb96c3db 100644
--- a/tests/auto/controls/data/tst_scrollview.qml
+++ b/tests/auto/controls/data/tst_scrollview.qml
@@ -41,6 +41,7 @@
 import QtQuick 2.2
 import QtTest 1.0
 import QtQuick.Controls 1.2
+import QtQuick.Controls.Styles 1.1
 import QtQuickControlsTests 1.0
 
 Item {
@@ -90,6 +91,68 @@ TestCase {
         scrollView.destroy()
     }
 
+    Component {
+        id: dragFetchAppendComponent
+
+        ScrollView {
+            width: 400; height: 400
+            frameVisible: false
+            style: ScrollViewStyle {
+                transientScrollBars: false
+                handle: Rectangle {
+                    implicitWidth: 16; implicitHeight: 16
+                    color: "red"
+                }
+                scrollBarBackground: Item {width: 16 ; height: 16}
+                incrementControl: Rectangle {
+                    width: 16; height: 16
+                    color: "blue"
+                }
+                decrementControl: Rectangle {
+                    width: 16; height: 16
+                    color: "blue"
+                }
+            }
+            ListView {
+                id: view
+
+                verticalLayoutDirection: ListView.BottomToTop
+                model: TestFetchAppendModel { }
+                delegate: Text {
+                    width: view.width
+                    height: 60
+                    verticalAlignment: Text.AlignVCenter
+                    horizontalAlignment: Text.AlignHCenter
+                    text: "Item %1".arg(model.index)
+                }
+            }
+        }
+    }
+
+    function test_dragFetchAppend() {   // QTBUG-50795
+        var scrollView = dragFetchAppendComponent.createObject(container)
+        verify(scrollView !== null, "view created is null")
+        waitForRendering(scrollView)
+        verify(scrollView.flickableItem.contentHeight === 60 * 20)
+
+        // After scrolling to the end, view should ask the model to fetch more
+        // data, content height should increase and scrollbar handle should move
+        // to the center.
+        mouseDrag(scrollView, scrollView.width - 2, scrollView.height - 8 - 16, 0, -scrollView.height + 8 + 16)
+        waitForRendering(scrollView)
+
+        // Move it again to fetch more data from the model.
+        mouseDrag(scrollView, scrollView.width - 2, scrollView.height / 2, 0, -scrollView.height / 2  + 8 + 16)
+        waitForRendering(scrollView)
+
+        mouseRelease(scrollView, scrollView.width - 2, 8 + 16)
+        waitForRendering(scrollView)
+
+        verify(Math.round(scrollView.flickableItem.contentHeight) > 60 * 20)
+        verify(Math.round(scrollView.flickableItem.contentY) < -(60 * 20))
+
+        scrollView.destroy()
+    }
 
     function test_scrollbars() {
         var component = scrollViewComponent
diff --git a/tests/auto/testplugin/testcppmodels.h b/tests/auto/testplugin/testcppmodels.h
index f5cc6298..6298bd13 100644
--- a/tests/auto/testplugin/testcppmodels.h
+++ b/tests/auto/testplugin/testcppmodels.h
@@ -96,6 +96,58 @@ private:
     QList<TestObject> m_testobject;
 };
 
+class TestFetchAppendModel : public QAbstractListModel
+{
+    Q_OBJECT
+public:
+    explicit TestFetchAppendModel(QObject *parent = 0)
+        : QAbstractListModel(parent) { }
+
+    virtual int rowCount(const QModelIndex &parent) const
+    {
+        if (parent.isValid()) {
+            return 0;
+        }
+
+        return m_data.size();
+    }
+    virtual QVariant data(const QModelIndex &index, int role) const
+    {
+        if (!index.isValid() || role != Qt::DisplayRole) {
+            return QVariant();
+        }
+
+        return QVariant::fromValue(index.row());
+    }
+
+    virtual bool canFetchMore(const QModelIndex &parent) const
+    {
+        Q_UNUSED(parent)
+
+        return true;
+    }
+    virtual void fetchMore(const QModelIndex & parent)
+    {
+        Q_UNUSED(parent)
+
+        addMoreData();
+    }
+
+private:
+    void addMoreData()
+    {
+        static const int insertCount = 20;
+
+        beginInsertRows(QModelIndex(), m_data.size(), m_data.size() + insertCount - 1);
+        for (int i = 0; i < insertCount; i++) {
+            m_data.append(int());
+        }
+        endInsertRows();
+    }
+
+    QList<int> m_data;
+};
+
 
 #endif // TESTCPPMODELS_H
 
diff --git a/tests/auto/testplugin/testplugin.cpp b/tests/auto/testplugin/testplugin.cpp
index 0f23f0b4..ee6a9711 100644
--- a/tests/auto/testplugin/testplugin.cpp
+++ b/tests/auto/testplugin/testplugin.cpp
@@ -48,6 +48,7 @@ void TestPlugin::registerTypes(const char *uri)
     qmlRegisterType<TestObject>(uri, 1, 0, "TestObject");
     qmlRegisterType<TestItemModel>(uri, 1, 0, "TestItemModel");
     qmlRegisterType<TestModel>(uri, 1, 0, "TreeModel");
+    qmlRegisterType<TestFetchAppendModel>(uri, 1, 0, "TestFetchAppendModel");
 }
 
 void TestPlugin::initializeEngine(QQmlEngine *engine, const char * /*uri*/)