Bug 312859 The list of operator for Chart filter does not provide 30 visible items
chart/org.eclipse.birt.chart.reportitem.ui/src/org/eclipse/birt/chart/reportitem/ui/dialogs/ChartCubeFilterConditionBuilder.java
}
		}
		
		columnList = new ArrayList<String>( );
	}
	protected String adaptExpr( ExpressionCodec exprCodec )
	{
		Expression expr = new Expression( exprCodec.getExpression( ),
				exprCodec.getType( ) );
		IModelAdapter adapter = getDteSession( ).getModelAdaptor( );
		return adapter.adaptExpression( expr, ExpressionLocation.CUBE )
				.getText( );
	}
	protected Map<String, String> getValidFilterExpressions(
			ExtendedItemHandle handle ) throws ExtendedElementException
	{
		Map<String, String> exprMap = new LinkedHashMap<String, String>( );
		
		
		for ( LevelHandle lh : ChartCubeUtil.getAllLevels( handle.getCube( ) ) )
		{
			exprCodec.setBindingName( ChartCubeUtil.createLevelBindingName( lh ),
					true );
			String expr = adaptExpr( exprCodec );
			exprMap.put( exprCodec.getBindingName( ), expr ); 
		}
		for ( MeasureHandle mh : ChartCubeUtil.getAllMeasures( handle.getCube( ) ) )
		{
			exprCodec.setBindingName( ChartCubeUtil.createMeasureBindingName( mh ),
					true );