Question

How we can hide a row at specific index of DataGrid in AS3 ?

Answer 1

If dataProvider of your DataGrid is ArrayCollection you can specify filterFunction property for it, something like that

dataProvider.filterFunction =
    function (item:Object):Boolean{
        if (dataProvider.getItemIndex(item)==indexOfRowYouWantToHide){
            return false;
        }
        return true;
    };

The item will still be in ArrayCollection but will be made invisible by the filter. Not the most efficient solution but it works. You need to call

dataProvider.refresh();

to apply the filter.

UPDATE: To access raw, unfiltered data of ArrayCollection you should use list property, so if you hid item at index 0 and still want to be able to access it you do that like this:

dataProvider.list.getItemAt(0);