Bug 313297 XML data set fail in chart data preview
chart/org.eclipse.birt.chart.ui/src/org/eclipse/birt/chart/ui/swt/CustomPreviewTable.java
fireMenuEvent( btnHeader, false );
		
		addHeaderSplitter( );
	}
	private void addHeaderButton( int style, ColumnBindingInfo columnHeader,
			int iWidth , int index)
	{
		Button btnHeader = new Button( cmpHeaders, style );
		
		btnHeader.setText( columnHeader.getName( ) );
		if ( columnHeader.getImageName( ) != null )
		{
			btnHeader.setImage( UIHelper.getImage( columnHeader.getImageName( ) ) );
		}
		if ( columnHeader.getTooltip( ) != null )
		{
			btnHeader.setToolTipText( columnHeader.getTooltip( ) );
		}
		
		FormData fd = new FormData( );
		fd.top = new FormAttachment( 2 );
		int i = btnHeaders.size( );
		if ( i == 0 )
		{
			fd.left = new FormAttachment( 0 );
		}
		else
		{
			Button btnNeighbor = btnHeaders.get( i - 1 );
			fd.left = new FormAttachment( btnNeighbor, SPLITTER_WIDTH );