eliminate global access to Octave resources in qt graphics classes Provide reference to base_qobject to qt graphics classes to eliminate need for accessing it through a global variable. * qt-graphics-toolkit.h, qt-graphics-toolkit.cc (qt_graphics_toolkit::m_octave_qobj): New member variable. (qt_graphics_toolkit::qt_graphics_toolkit): Accept reference to base_qobject as argument. (qt_graphics_toolkit::create_object): Pass m_octave_qobj to create functions for individual graphics objects. * __init_qt__.cc (__init__): Temporarily access base_qobject by calling octave::base_qobject::the_octave_qobject. Pass it to qt_graphics_toolkit constructor. * BaseControl.h, BaseControl.cc, ButtonControl.h, ButtonControl.cc, ButtonGroup.h, ButtonGroup.cc, Canvas.h, Canvas.cc, CheckBoxControl.h, CheckBoxControl.cc, Container.h, Container.cc, ContextMenu.h, ContextMenu.cc, EditControl.h, EditControl.cc, Figure.h, Figure.cc, GLCanvas.h, GLCanvas.cc, ListBoxControl.h, ListBoxControl.cc, Menu.h, Menu.cc, Panel.h, Panel.cc, PopupMenuControl.h, PopupMenuControl.cc, PushButtonControl.h, PushButtonControl.cc, PushTool.h, PushTool.cc, RadioButtonControl.h, RadioButtonControl.cc, SliderControl.h, SliderControl.cc, Table.h, Table.cc, TextControl.h, TextControl.cc, ToggleButtonControl.h, ToggleButtonControl.cc, ToggleTool.h, ToggleTool.cc, ToolBar.h, ToolBar.cc, ToolBarButton.h, ToolBarButton.cc, annotation-dialog.h, annotation-dialog.cc: Accept reference to base_qobject in create function and constructors for graphics objects. Eliminate global access to GUI resources.

--- a/libgui/graphics/PushButtonControl.cc	Tue Nov 05 08:31:06 2019 -0500
+++ b/libgui/graphics/PushButtonControl.cc	Tue Nov 05 13:28:45 2019 -0500
@@ -31,11 +31,14 @@
 #include "Container.h"
 #include "QtHandlesUtils.h"
 
+#include "octave-qobject.h"
+
 namespace QtHandles
 {
 
   PushButtonControl*
-  PushButtonControl::create (const graphics_object& go)
+  PushButtonControl::create (octave::base_qobject& oct_qobj,
+                             const graphics_object& go)
   {
     Object *parent = Object::parentObject (go);
 
@@ -44,15 +47,17 @@
         Container *container = parent->innerContainer ();
 
         if (container)
-          return new PushButtonControl (go, new QPushButton (container));
+          return new PushButtonControl (oct_qobj, go,
+                                        new QPushButton (container));
       }
 
     return nullptr;
   }
 
-  PushButtonControl::PushButtonControl (const graphics_object& go,
+  PushButtonControl::PushButtonControl (octave::base_qobject& oct_qobj,
+                                        const graphics_object& go,
                                         QPushButton *btn)
-    : ButtonControl (go, btn)
+    : ButtonControl (oct_qobj, go, btn)
   {
     uicontrol::properties& up = properties<uicontrol> ();