setFieldErrors doesn't show the error in the ListGrid

[ade045es]

Hello:

This my first question in this forum. I am new smartgwt developer and I have a lot of questions. But I write only to ask about one problem.

I have to do a validation when a listgrid cell changes. The validation is that can't exist the same value in the column twice.

The code is this:

ListGridField itemIdField = new ListGridField("itemId", RECTIFICATIONS_MESSAGES.fieldItemId()); 
		itemIdField.setRequired(true);
		itemIdField.setCanEdit(true);
		itemIdField.setType(ListGridFieldType.INTEGER);
		IntegerRangeValidator itemIdRange = new IntegerRangeValidator();
		itemIdRange.setMin(0);
		itemIdRange.setMax(999999);

itemIdField.setValidators(itemIdRange);
		
		
				
		
		
		itemIdField.addChangedHandler(new ChangedHandler() {
			
			@Override
			public void onChanged(ChangedEvent event) {
				GWT.log("OnChanged " +event.getValue().getClass().getName());
				
				String value = event.getValue().toString();
				
				String field_name = getFieldName(event.getColNum());
				GWT.log("fieldName : " + field_name);
				Record[] records = getRecordList().findAll(field_name, value);				
				int times = (records == null) ? 0 : records.length;
				
				if (times != 0){
				String error_msg = "No se puede poner el item " + value + " " + times + " veces .";
				
				
				setFieldError(event.getRowNum(),field_name,error_msg);
			    
			    
				refreshCell(event.getRowNum(), event.getColNum());
				refreshRecordComponent(event.getRowNum(), event.getColNum());
				refreshRow(event.getRowNum());
				refreshRecordComponent(event.getRowNum());
				redraw();
				
				GWT.log(error_msg);
				}
			}
		});

The found behaivour is that the cell doesn't show the error and the cell doesn't allow write the same value twice.

What am I doing wrong?