- Window xwindow = (Window) m_mainWindow;
- wxDeleteWindowFromTable( xwindow );
- XDestroyWindow( wxGlobalDisplay(), xwindow );
- m_mainWindow = NULL;
+ if ( m_mainWindow )
+ {
+ Window xwindow = (Window) m_mainWindow;
+ wxDeleteWindowFromTable( xwindow );
+ XDestroyWindow( wxGlobalDisplay(), xwindow );
+ m_mainWindow = NULL;
+ }