Allow setting custom tooltip text for "New" button in wxPGArrayEditorDialog

Ability to change the tooltip can be useful if standard text "New item" is not descriptive enough.

include/wx/propgrid/props.h

@@ -796,8 +796,7 @@ wxValidator* PROPNAME::DoGetValidator () const \
 
 #if wxUSE_EDITABLELISTBOX
 
-class WXDLLIMPEXP_FWD_CORE wxEditableListBox;
-class WXDLLIMPEXP_FWD_CORE wxListEvent;
+#include "wx/editlbox.h"
 
 #define wxAEDIALOG_STYLE \
     (wxDEFAULT_DIALOG_STYLE | wxRESIZE_BORDER | wxOK | wxCANCEL | wxCENTRE)
@@ -829,6 +828,15 @@ public:
         m_hasCustomNewAction = true;
     }
 
+    void SetNewButtonText(const wxString& text)
+    {
+        m_customNewButtonText = text;
+        if ( m_elb && m_elb->GetNewButton() )
+        {
+            m_elb->GetNewButton()->SetToolTip(text);
+        }
+    }
+
     // Set value modified by dialog.
     virtual void SetDialogValue( const wxVariant& WXUNUSED(value) )
     {
@@ -880,6 +888,7 @@ protected:
 
     bool            m_modified;
     bool            m_hasCustomNewAction;
+    wxString        m_customNewButtonText;
 
     // These must be overridden - must return true on success.
     virtual wxString ArrayGet( size_t index ) = 0;
@@ -929,6 +938,7 @@ public:
         if ( !custBtText.empty() )
         {
             EnableCustomNewAction();
+            SetNewButtonText(custBtText);
             m_pCallingClass = pcc;
         }
     }