Refs #11947 Hedge for empty active source

Vates/VatesSimpleGui/ViewWidgets/inc/MantidVatesSimpleGuiViewWidgets/ViewBase.h

@@ -145,6 +145,8 @@ public:
   void setColorScaleLock(Mantid::VATES::ColorScaleLock* colorScaleLock);
   QPointer<pqPipelineSource> origSrc; ///< The original source
   QPointer<pqPipelineRepresentation> origRep; ///< The original source representation
+  /// Has active source
+  bool hasActiveSource();
 
 public slots:
   /// Set the color scale back to the original bounds.

Vates/VatesSimpleGui/ViewWidgets/src/StandardView.cpp

@@ -229,6 +229,11 @@ void StandardView::render()
 }
 
 void StandardView::onCutButtonClicked() {
+  // check that has active source
+  if (!hasActiveSource()) {
+    return;
+  }
+
   // Apply cut to currently viewed data
   pqObjectBuilder *builder = pqApplicationCore::instance()->getObjectBuilder();
   builder->createFilter("filters", "Cut", this->getPvActiveSrc());
@@ -239,6 +244,11 @@ void StandardView::onCutButtonClicked() {
 }
 
 void StandardView::onScaleButtonClicked() {
+  // check that has active source
+  if (!hasActiveSource()) {
+    return;
+  }
+
   pqObjectBuilder *builder = pqApplicationCore::instance()->getObjectBuilder();
   this->m_scaler = builder->createFilter(
       "filters", "MantidParaViewScaleWorkspace", this->getPvActiveSrc());

Vates/VatesSimpleGui/ViewWidgets/src/ViewBase.cpp

@@ -954,6 +954,13 @@ void ViewBase::setAxesGrid(bool on) {
   }
 }
 
+/**
+ * Check if there is an active source available
+ * @returns true if there is an active source else false
+ */
+bool ViewBase::hasActiveSource() {
+  return this->getPvActiveSrc() != nullptr;
+}
 
 } // namespace SimpleGui
 } // namespace Vates