tdf#125538 fix background of zoom control

by
(a) invalidating parent, which repaints the background
(b) making the background of the zoom control transparent, so the
   toolbar is visible behind it

Change-Id: I75e67e6c820dccf8bf8a001965df7b5e49176bfa
Reviewed-on: https://gerrit.libreoffice.org/c/core/+/94439
Tested-by: Noel Grandin <noel.grandin@collabora.co.uk>
Reviewed-by: Noel Grandin <noel.grandin@collabora.co.uk>

2 files changed, 15 insertions, 30 deletions

diff --git a/sc/source/ui/cctrl/tbzoomsliderctrl.cxx b/sc/source/ui/cctrl/tbzoomsliderctrl.cxx
index 49679131a18b..e6214f8e05e1 100644
--- a/sc/source/ui/cctrl/tbzoomsliderctrl.cxx
+++ b/sc/source/ui/cctrl/tbzoomsliderctrl.cxx
@@ -97,8 +97,9 @@ struct ScZoomSlider::ScZoomSliderWnd_Impl
     Image                    maIncreaseButton;
     Image                    maDecreaseButton;
     bool                     mbOmitPaint;
+    vcl::Window*             mpParentWindow;
 
-    explicit ScZoomSliderWnd_Impl( sal_uInt16 nCurrentZoom ) :
+    explicit ScZoomSliderWnd_Impl( sal_uInt16 nCurrentZoom, vcl::Window* parentWindow ) :
         mnCurrentZoom( nCurrentZoom ),
         mnMinZoom( 10 ),
         mnMaxZoom( 400 ),
@@ -107,7 +108,8 @@ struct ScZoomSlider::ScZoomSliderWnd_Impl
         maSliderButton(),
         maIncreaseButton(),
         maDecreaseButton(),
-        mbOmitPaint( false )
+        mbOmitPaint( false ),
+        mpParentWindow(parentWindow)
         {
         }
 };
@@ -207,7 +209,7 @@ ScZoomSliderWnd::ScZoomSliderWnd( vcl::Window* pParent,
                 const css::uno::Reference< css::frame::XDispatchProvider >& rDispatchProvider,
                 sal_uInt16 nCurrentZoom ):
                 InterimItemWindow(pParent, "modules/scalc/ui/zoombox.ui", "ZoomBox"),
-                mxWidget(new ScZoomSlider(rDispatchProvider, nCurrentZoom)),
+                mxWidget(new ScZoomSlider(rDispatchProvider, nCurrentZoom, pParent)),
                 mxWeld(new weld::CustomWeld(*m_xBuilder, "zoom", *mxWidget))
 {
     Size aLogicalSize( 115, 40 );
@@ -231,8 +233,8 @@ void ScZoomSliderWnd::dispose()
 }
 
 ScZoomSlider::ScZoomSlider(const css::uno::Reference< css::frame::XDispatchProvider>& rDispatchProvider,
-                           sal_uInt16 nCurrentZoom)
-    : mpImpl(new ScZoomSliderWnd_Impl(nCurrentZoom))
+                           sal_uInt16 nCurrentZoom, vcl::Window* parentWindow)
+    : mpImpl(new ScZoomSliderWnd_Impl(nCurrentZoom, parentWindow))
     , m_xDispatchProvider(rDispatchProvider)
 {
     mpImpl->maSliderButton      = Image(StockImage::Yes, RID_SVXBMP_SLIDERBUTTON);
@@ -275,9 +277,8 @@ bool ScZoomSlider::MouseButtonDown( const MouseEvent& rMEvt )
     if( nOldZoom == mpImpl->mnCurrentZoom )
         return true;
 
-    tools::Rectangle aRect( Point( 0, 0 ), aSliderWindowSize );
-
-    Invalidate(aRect);
+    // need to invalidate parent since we rely on the toolbox drawing it's fancy gradient background
+    mpImpl->mpParentWindow->Invalidate();
     mpImpl->mbOmitPaint = true;
 
     SvxZoomSliderItem   aZoomSliderItem( mpImpl->mnCurrentZoom );
@@ -311,8 +312,8 @@ bool ScZoomSlider::MouseMove( const MouseEvent& rMEvt )
         {
             mpImpl->mnCurrentZoom = Offset2Zoom( aPoint.X() );
 
-            tools::Rectangle aRect(Point(0, 0), aSliderWindowSize);
-            Invalidate(aRect);
+            // need to invalidate parent since we rely on the toolbox drawing it's fancy gradient background
+            mpImpl->mpParentWindow->Invalidate();
 
             mpImpl->mbOmitPaint = true; // optimization: paint before executing command,
 
@@ -378,11 +379,9 @@ void ScZoomSlider::UpdateFromItem(const SvxZoomSliderItem* pZoomSliderItem)
         }
     }
 
-    Size aSliderWindowSize = GetOutputSizePixel();
-    tools::Rectangle aRect(Point(0, 0), aSliderWindowSize);
-
     if ( !mpImpl->mbOmitPaint )
-       Invalidate(aRect);
+        // need to invalidate parent since we rely on the toolbox drawing it's fancy gradient background
+        mpImpl->mpParentWindow->Invalidate();
 }
 
 void ScZoomSlider::Paint(vcl::RenderContext& rRenderContext, const tools::Rectangle& /*rRect*/)
@@ -399,6 +398,7 @@ void ScZoomSlider::DoPaint(vcl::RenderContext& rRenderContext)
     tools::Rectangle aRect(Point(0, 0), aSliderWindowSize);
 
     ScopedVclPtrInstance< VirtualDevice > pVDev(rRenderContext);
+    pVDev->SetBackground(Wallpaper(COL_TRANSPARENT));
     pVDev->SetOutputSizePixel(aSliderWindowSize);
 
     tools::Rectangle aSlider = aRect;
@@ -420,21 +420,6 @@ void ScZoomSlider::DoPaint(vcl::RenderContext& rRenderContext)
     tools::Rectangle aRight(aSlider);
     aRight.SetLeft( aRight.Right() );
 
-    // draw VirtualDevice's background color
-    Color aStartColor = rRenderContext.GetSettings().GetStyleSettings().GetFaceColor();
-    Color aEndColor   = rRenderContext.GetSettings().GetStyleSettings().GetFaceColor();
-
-    if (aEndColor.IsDark())
-        aStartColor = aEndColor;
-
-    Gradient aGradient;
-    aGradient.SetAngle(0);
-    aGradient.SetStyle(GradientStyle::Linear);
-
-    aGradient.SetStartColor(aStartColor);
-    aGradient.SetEndColor(aEndColor);
-    pVDev->DrawGradient(aRect, aGradient);
-
     // draw slider
     pVDev->SetLineColor(COL_WHITE);
     pVDev->DrawRect(aSecondLine);
diff --git a/sc/source/ui/inc/tbzoomsliderctrl.hxx b/sc/source/ui/inc/tbzoomsliderctrl.hxx
index 3f22ba1b4b9e..815e15c104c1 100644
--- a/sc/source/ui/inc/tbzoomsliderctrl.hxx
+++ b/sc/source/ui/inc/tbzoomsliderctrl.hxx
@@ -53,7 +53,7 @@ private:
     void DoPaint(vcl::RenderContext& rRenderContext);
 public:
     ScZoomSlider(const css::uno::Reference<css::frame::XDispatchProvider>& rDispatchProvider,
-                 sal_uInt16 nCurrentZoom);
+                 sal_uInt16 nCurrentZoom, vcl::Window*);
 
     void UpdateFromItem(const SvxZoomSliderItem* pZoomSliderItem);