AS2 Subclasses and component access

programming flash
1

Hello. I have a grid (instance: mainTable) that is contained in a MovieClip that I attach at runtime via attachMovie(). This movie clip is linked to an actionscript file that defines a class.

import mx.controls.DataGrid;
import mx.controls.gridclasses.DataGridColumn;

class ContentTableMC extends MovieClip
{
private var mainTable:DataGrid;

function ContentTableMC() { 
     init(); 
}

function init() {
this._x = 183;
this._y = 130;

    mainTable:.addColumn(new DataGridColumn("Red")); 
    mainTable:.addColumn(new DataGridColumn("Green")); 
    mainTable:.addColumn(new DataGridColumn("Blue")); 

    trace("Table columns: " + this. mainTable.columnNames);

}
}

Attach code:

contentArea_mc = attachMovie(“ContentAreaReportMC”, “contentArea_mc”, 1);

The trace statement in the init() function returns undefined ?

I cannot figure this out ? I cannot seem to access the datagrid or any other component I add to this movieclip?

Thank you,
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