called when a rendering is in its preparing phase . concode_field_sep PlaceHolder placeHolder concode_field_sep void gvtRenderingCompleted concode_elem_sep void gvtRenderingStarted concode_elem_sep void gvtRenderingCancelled concode_elem_sep void gvtRenderingFailed
void function ( GVTTreeRendererEvent arg0 ) { }