tdf#124410 re-call SetScrollBarRange when aSymbolSet changes

and do the work that depends on size happen at size-changed
instead of first-draw

Change-Id: Ia2605ba9bb875be9248a009a6f26f01cbbbd4632
Reviewed-on: https://gerrit.libreoffice.org/69928
Tested-by: Jenkins
Reviewed-by: Caolán McNamara <caolanm@redhat.com>
Tested-by: Caolán McNamara <caolanm@redhat.com>

starmath/inc/dialog.hxx

@@ -259,6 +259,7 @@ class SmShowSymbolSet : public weld::CustomWidgetController
     virtual void Paint(vcl::RenderContext& rRenderContext, const tools::Rectangle& rRect) override;
     virtual bool MouseButtonDown(const MouseEvent& rMEvt) override;
     virtual bool KeyInput(const KeyEvent& rKEvt) override;
+    virtual void Resize() override;
 
     DECL_LINK(ScrollHdl, weld::ScrolledWindow&, void);
 
@@ -268,8 +269,11 @@ public:
     virtual void SetDrawingArea(weld::DrawingArea* pDrawingArea) override
     {
         CustomWidgetController::SetDrawingArea(pDrawingArea);
-        pDrawingArea->set_size_request(pDrawingArea->get_approximate_digit_width() * 27,
-                                       pDrawingArea->get_text_height() * 9);
+        m_aOldSize = Size(pDrawingArea->get_approximate_digit_width() * 27,
+                          pDrawingArea->get_text_height() * 9);
+        pDrawingArea->set_size_request(m_aOldSize.Width(), m_aOldSize.Height());
+        SetOutputSizePixel(m_aOldSize);
+        calccols(pDrawingArea->get_ref_device());
     }
 
     void calccols(const vcl::RenderContext& rRenderContext);

starmath/source/dialog.cxx

@@ -940,15 +940,19 @@ Point SmShowSymbolSet::OffsetPoint(const Point &rPoint) const
     return Point(rPoint.X() + nXOffset, rPoint.Y() + nYOffset);
 }
 
-void SmShowSymbolSet::Paint(vcl::RenderContext& rRenderContext, const tools::Rectangle&)
+void SmShowSymbolSet::Resize()
 {
+    CustomWidgetController::Resize();
     Size aWinSize(GetOutputSizePixel());
     if (aWinSize != m_aOldSize)
     {
-        calccols(rRenderContext);
+        calccols(GetDrawingArea()->get_ref_device());
         m_aOldSize = aWinSize;
     }
+}
 
+void SmShowSymbolSet::Paint(vcl::RenderContext& rRenderContext, const tools::Rectangle&)
+{
     Color aBackgroundColor;
     Color aTextColor;
     lclGetSettingColors(aBackgroundColor, aTextColor);
@@ -1088,6 +1092,7 @@ void SmShowSymbolSet::calccols(const vcl::RenderContext& rRenderContext)
 void SmShowSymbolSet::SetSymbolSet(const SymbolPtrVec_t& rSymbolSet)
 {
     aSymbolSet = rSymbolSet;
+    SetScrollBarRange();
     Invalidate();
 }