Add scrollPosition API

Adds an API to read the main-frame scrollPosition.

In QtWebKit this property used to be in QWebFrame.

Task-number: QTBUG-48323
Change-Id: Ic8312afac0dcdcfd8c7fd4589be774d327bb6268
Reviewed-by: Michael Brüning <michael.bruning@theqtcompany.com>

5 files changed, 20 insertions, 0 deletions

diff --git a/src/core/render_widget_host_view_qt.cpp b/src/core/render_widget_host_view_qt.cpp
index 26ea4f4ae..bf0e80be9 100644
--- a/src/core/render_widget_host_view_qt.cpp
+++ b/src/core/render_widget_host_view_qt.cpp
@@ -628,6 +628,7 @@ bool RenderWidgetHostViewQt::HasAcceleratedSurface(const gfx::Size&)
 
 void RenderWidgetHostViewQt::OnSwapCompositorFrame(uint32 output_surface_id, scoped_ptr<cc::CompositorFrame> frame)
 {
+    bool scrollOffsetChanged = (m_lastScrollOffset != frame->metadata.root_scroll_offset);
     m_lastScrollOffset = frame->metadata.root_scroll_offset;
     Q_ASSERT(!m_needsDelegatedFrameAck);
     m_needsDelegatedFrameAck = true;
@@ -648,6 +649,9 @@ void RenderWidgetHostViewQt::OnSwapCompositorFrame(uint32 output_surface_id, sco
         m_adapterClient->loadVisuallyCommitted();
         m_didFirstVisuallyNonEmptyLayout = false;
     }
+
+    if (scrollOffsetChanged)
+        m_adapterClient->updateScrollPosition(toQt(m_lastScrollOffset));
 }
 
 void RenderWidgetHostViewQt::GetScreenInfo(blink::WebScreenInfo* results)
diff --git a/src/core/type_conversion.h b/src/core/type_conversion.h
index 9e5461888..0cefeb07a 100644
--- a/src/core/type_conversion.h
+++ b/src/core/type_conversion.h
@@ -94,6 +94,11 @@ inline QPoint toQt(const gfx::Point &point)
     return QPoint(point.x(), point.y());
 }
 
+inline QPointF toQt(const gfx::Vector2dF &point)
+{
+    return QPointF(point.x(), point.y());
+}
+
 inline gfx::Point toGfx(const QPoint& point)
 {
   return gfx::Point(point.x(), point.y());
diff --git a/src/core/web_contents_adapter.cpp b/src/core/web_contents_adapter.cpp
index 2b2512fc3..8f69fb92c 100644
--- a/src/core/web_contents_adapter.cpp
+++ b/src/core/web_contents_adapter.cpp
@@ -829,6 +829,14 @@ void WebContentsAdapter::wasHidden()
     d->webContents->WasHidden();
 }
 
+QPointF WebContentsAdapter::lastScrollOffset() const
+{
+    Q_D(const WebContentsAdapter);
+    if (content::RenderWidgetHostView *rwhv = d->webContents->GetRenderWidgetHostView())
+        return toQt(rwhv->GetLastScrollOffset());
+    return QPointF();
+}
+
 void WebContentsAdapter::grantMediaAccessPermission(const QUrl &securityOrigin, WebContentsAdapterClient::MediaRequestFlags flags)
 {
     Q_D(WebContentsAdapter);
diff --git a/src/core/web_contents_adapter.h b/src/core/web_contents_adapter.h
index ecb084e56..39cc48834 100644
--- a/src/core/web_contents_adapter.h
+++ b/src/core/web_contents_adapter.h
@@ -143,6 +143,8 @@ public:
     QWebChannel *webChannel() const;
     void setWebChannel(QWebChannel *);
 
+    QPointF lastScrollOffset() const;
+
     // meant to be used within WebEngineCore only
     content::WebContents *webContents() const;
 
diff --git a/src/core/web_contents_adapter_client.h b/src/core/web_contents_adapter_client.h
index 3ae84f9c8..94c6835ed 100644
--- a/src/core/web_contents_adapter_client.h
+++ b/src/core/web_contents_adapter_client.h
@@ -236,6 +236,7 @@ public:
     virtual void renderProcessTerminated(RenderProcessTerminationStatus terminationStatus, int exitCode) = 0;
 
     virtual void allowCertificateError(const QSharedPointer<CertificateErrorController> &errorController) = 0;
+    virtual void updateScrollPosition(const QPointF &position) = 0;
 
     virtual BrowserContextAdapter* browserContextAdapter() = 0;