Setting String to DataGridColumn.cellRenderer property

Reference of a class to render the items in a column can be set to DataGridColumn.cellRenderer property as the following frame action:

// Frame action
import fl.controls.DataGrid;
import fl.controls.dataGridClasses.DataGridColumn;
var myColmn:DataGridColumn = new DataGridColumn("data");
var myDataGrid:DataGrid = new DataGrid();
myDataGrid.addColumn(myColmn);
// myColmn.cellRenderer = "CustomCellRenderer";  // Error #2007
myColmn.cellRenderer = CustomCellRenderer;  // OK
myDataGrid.addItem({data: "test"});
addChild(myDataGrid);

[Help] also tells that the type of the property’s value can be String. However setting a String class name causes Error #2007 like the below. The error would be shown if the comment-outed statement was validated instead in the sample above.

TypeError:Error #2007:Parameter child must be non-null.

I happened to see DataGridColumn.cellRenderer property in ActionScript 2.0 Components Language Reference. It says that the property is “a linkage identifier for a symbol”.

Therefore, I tried to create an empty MovieClip symbol and to set the class to [Class] of [Linkage]. Then the String class name set to the property in the code above worked properly without an error. As my conclusion, a String class name might only be used for the class set to [Class] of [Linkage].