ENH: The interactor must be set before enabling the widget.

When the method WidgetIsDefined() is called (ie the widget is defined
programmatically) and then the method SetEnabled is invoked, we run
into a bug, in that the internal HandleWidgets are enabled without
having their interactors set. Hence propagate the interactor from self
into the child widgets always.

Widgets/vtkAngleWidget.cxx

@@ -174,18 +174,18 @@ void vtkAngleWidget::SetEnabled(int enabling)
         reinterpret_cast<vtkAngleRepresentation*>(this->WidgetRep)->
           ArcVisibilityOn();
         }
-      if (this->Point1Widget)
-        {
-        this->Point1Widget->SetEnabled(1);
-        }
-      if (this->CenterWidget)
-        {
-        this->CenterWidget->SetEnabled(1);
-        }
-      if (this->Point2Widget)
+
+      // The interactor must be set prior to enabling the widget.
+      if (this->Interactor)
         {
-        this->Point2Widget->SetEnabled(1);
+        this->Point1Widget->SetInteractor(this->Interactor);
+        this->CenterWidget->SetInteractor(this->Interactor);
+        this->Point2Widget->SetInteractor(this->Interactor);
         }
+
+      this->Point1Widget->SetEnabled(1);
+      this->CenterWidget->SetEnabled(1);
+      this->Point2Widget->SetEnabled(1);
       }
     }
 

Widgets/vtkBiDimensionalWidget.cxx

@@ -198,22 +198,20 @@ void vtkBiDimensionalWidget::SetEnabled(int enabling)
         vtkBiDimensionalRepresentation2D::SafeDownCast(this->WidgetRep)->
           Line2VisibilityOn();
         }
-      if (this->Point1Widget)
-        {
-        this->Point1Widget->SetEnabled(1);
-        }
-      if (this->Point2Widget)
-        {
-        this->Point2Widget->SetEnabled(1);
-        }
-      if (this->Point3Widget)
-        {
-        this->Point3Widget->SetEnabled(1);
-        }
-      if (this->Point4Widget)
+
+      // The interactor must be set prior to enabling the widget.
+      if (this->Interactor)
         {
-        this->Point4Widget->SetEnabled(1);
+        this->Point1Widget->SetInteractor(this->Interactor);
+        this->Point2Widget->SetInteractor(this->Interactor);
+        this->Point3Widget->SetInteractor(this->Interactor);
+        this->Point4Widget->SetInteractor(this->Interactor);
         }
+
+      this->Point1Widget->SetEnabled(1);
+      this->Point2Widget->SetEnabled(1);
+      this->Point3Widget->SetEnabled(1);
+      this->Point4Widget->SetEnabled(1);
       }
     }
 

Widgets/vtkDistanceWidget.cxx

@@ -143,6 +143,13 @@ void vtkDistanceWidget::SetEnabled(int enabling)
       }
     else
       {
+      // The interactor must be set prior to enabling the widget.
+      if (this->Interactor)
+        {
+        this->Point1Widget->SetInteractor(this->Interactor);
+        this->Point2Widget->SetInteractor(this->Interactor);
+        }
+
       this->Point1Widget->SetEnabled(1);
       this->Point2Widget->SetEnabled(1);
       }