fix bug show() is called at the end of prg

ChangeLog.md

@@ -18,6 +18,10 @@
 
 
 - *IO Package*
+
+ - Viewer3D: Fix a problem when the show() method was called at the end of the
+   main program (the list creation was not called).
+   (Bertrand Kerautret [##1138](https://github.com/DGtal-team/DGtal/pull/1138))
  - Viewer3D: add three new modes for shape rendering (default, metallic and
    plastic). The rendering can be changed by using the key M. The user can
    also choose its own rendering with some setter/getter on the opengl

src/DGtal/io/viewers/Viewer3D.h

@@ -638,6 +638,15 @@ namespace DGtal
     virtual void paintGL();
 
 
+    /**
+     *  @brief Overload QWidget method in order to add a call to
+     * updateList() method (to ensure that the lists are well created
+     * in the particular case where show() is called at the end of the
+     * program).
+     **/    
+    virtual void show();
+
+
     /**
      * Add a TextureImage in the list of image to be displayed.
      * @param image a TextureImage including image data buffer and position, orientation.

src/DGtal/io/viewers/Viewer3D.ih

@@ -1879,7 +1879,13 @@ DGtal::Viewer3D<Space, KSpace>::setGLLightSpecularCoefficients(const GLfloat lig
 }
 
 
-
+template<typename Space, typename KSpace>
+inline
+void 
+DGtal::Viewer3D<Space, KSpace>::show(){
+  QGLWidget::show();
+  updateList(false);
+}
 
 
 template<typename Space, typename KSpace>