private void surfaceListBox1_SelectionChanged(object sender, SelectionChangedEventArgs e)
        {
            //   if (SurfaceWindow1.StaticIsListPhotoInsert() == true) return;
            if (surfaceListBox1.SelectedIndex == -1) return;

            if (stackNode.Count() == 0)
            {
                 // Le -1 est la pour compensé l'element choix par date dans la surfaceListBox.
                 XmlElement elm = xmlCat.getCurrentElem(surfaceListBox1.SelectedIndex);
                 if (elm.ChildNodes.Count == 0)
                 {
                   ListPhotosPage pp = new ListPhotosPage(elm);
                   SurfaceWindow1.staticSetBackPage(this, pp);
                   surfaceListBox1.SelectedIndex = -1;
                   }
                  else
                  {
                    stackNode.Push(currentElm);
                    currentElm = elm;
                    UpdateList();
                   }
            }
            else
            {

                            if( currentElm.ChildNodes.Count < surfaceListBox1.SelectedIndex ) { return; }
                            XmlElement elm = xmlCat.getCurrentChildElem(ref currentElm, surfaceListBox1.SelectedIndex );
                            if (elm  == null) return;
                            if (elm.ChildNodes.Count == 0)
                            {
                                ListPhotosPage pp = new ListPhotosPage(elm);
                                SurfaceWindow1.staticSetBackPage(this, pp);
                                surfaceListBox1.SelectedIndex = -1;
                            }
                            else
                            {
                                stackNode.Push(currentElm);
                                currentElm = elm;
                                UpdateList();
                            }
            }
        }
 private void buttonChild_TouchUp(object sender, TouchEventArgs e)
 {
     int indexButton = listChildCategory.Children.IndexOf((UIElement)sender);
     if (indexButton != -1)
     {
         CategoriesXml xmlcat = globalDatasingleton.getInstance().getCategories();
         ListPhotosPage lpp = new ListPhotosPage(xmlcat.GetChild(ref currentCat, indexButton));
         SurfaceWindow1.staticSetBackPage(this, lpp);
     }
 }