Bug 176450 Support link to CSS Feature(Model Part)
model/org.eclipse.birt.report.model/src/org/eclipse/birt/report/model/api/ReportDesignHandle.java
*/
	public void setRefreshRate( int rate )
	{
		try
		{
			setIntProperty( REFRESH_RATE_PROP, rate );
		}
		catch ( SemanticException e )
		{
			assert false;
		}
	}
	/**
	 * Returns a slot handle to work with the styles within the report. Note
	 * that the order of the styles within the slot is unimportant.
	 * 
	 * @return A handle for working with the styles.
	 */
	public SlotHandle getStyles( )
	{
		return getSlot( IReportDesignModel.STYLE_SLOT );
	}
	/*
	 * (non-Javadoc)
	 * 
	 * @see org.eclipse.birt.report.model.api.ModuleHandle#importCssStyles(org.eclipse.birt.report.model.api.css.CssStyleSheetHandle,
	 *      java.util.List)
	 */
	public void importCssStyles( CssStyleSheetHandle stylesheet,
			List selectedStyles )