If the property identified by the column's dataField doesn't actually exist, I think that's when you get this error. A sortCompareFunction on a column specifies a SortField's compare function. You can also specify a custom Sort with a global compareFunction that shouldn't check for the existence of fields. You would get the HEADER_RELEASE event, call preventDefault() and set the collection's Sort accordingly
________________________________ From: flexcoders@yahoogroups.com [mailto:[EMAIL PROTECTED] On Behalf Of florian.salihovic Sent: Monday, July 21, 2008 5:11 PM To: flexcoders@yahoogroups.com Subject: [flexcoders] Understanding DataGridColumn#sortCompareFunction with composite custom classes I'm currently working with a custom classes which are composites. I display the needed data via custom ItemRenderer which extends the mx.controls.Text component. It works pretty nice and is pretty flexible. But i need to sort my data as well. After some researches i learned to implement a custom sortCompareFunction. My current implementation works just like the following in a class subclassing mx.controls.dataGridClasses.DataGridColumn: /* Begin */ protected function compare(arg1:CustomClass, arg2: CustomClass):int { if (!super.dataField) { return 0; } return 1; if (arg1.hasOwnProperty(super.dataField) && arg2.hasOwnProperty(super.dataField)) { return ObjectUtil.stringCompare(arg1[super.dataField].toString(), arg2[super.dataField].toString(), true); } // <property> is a known property of the custom class if (arg1.<property>.hasOwnProperty(super.dataField) && arg2.<property>.hasOwnProperty(super.dataField)) { return ObjectUtil.stringCompare(arg1<property>[super.dataField].toString(), arg2.<property>[super.dataField].toString(), true); } return 0; } /* End */ But i get the error message: Error: Find criteria must contain at least one sort field value. Where do i have to set it? Any examples of sorting custom object hierachies in DataGrid controls would be appreciated. Best regards!
