Flex 3 DataGrid Component Losing Focus - actionscript-3

Question

I'm running into problems getting the focus to work on my custom datagrid. It is a subclass of MDataGrid which can be found here.
My problems is, that every other mouse click on inline components actually focuses on the component. The other clicks seem to automatically lose focus to something else, and I can't seem to figure out what is going on. Any help would be greatly appreciated.
Thanks for your time.
--Charly
<?xml version="1.0" encoding="utf-8"?>
<controls:MDataGrid xmlns:mx="http://www.adobe.com/2006/mxml"
xmlns:controls="com.iwobanas.controls.*"
xmlns:dgc="com.iwobanas.controls.dataGridClasses.*"
dataProvider="{locator.vendorInvoices}"
editable="true">
<mx:Script>
<![CDATA[
import model.PayablesLocator;
[Bindable] private var locator:PayablesLocator = PayablesLocator.getInstance();
]]>
</mx:Script>
<controls:columns>
<dgc:MDataGridColumn dataField="loadNumber"
headerText="Load"
editable="false"/>
<dgc:MDataGridColumn dataField="carrierName"
headerText="Carrier"
editable="false"/>
<mx:DataGridColumn headerText="Vendor Invoice #"
rendererIsEditor="true"
editorDataField="vendorInvoiceNumber">
<mx:itemRenderer>
<mx:Component>
<mx:HBox width="100%" height="100%" horizontalAlign="center" verticalAlign="middle"
implements="mx.controls.listClasses.IDropInListItemRenderer, mx.managers.IFocusManagerComponent">
<mx:Script>
<![CDATA[
import mx.controls.dataGridClasses.DataGridListData;
import mx.controls.listClasses.BaseListData;
import mx.events.FlexEvent;
private var _listData:DataGridListData;
[Bindable] public var vendorInvoiceNumber:String;
// Implements mx.managers.IFocusManagerComponent
override public function drawFocus(draw:Boolean):void {
invoiceNumberInput.setFocus();
}
// Implements mx.controls.listClasses.IDropInListItemRenderer
override public function get data():Object {
return super.data;
}
override public function set data(value:Object):void {
super.data = value;
invoiceNumberInput.text = data.vendorInvoiceNumber
}
public function get listData():BaseListData {
return _listData;
}
public function set listData(value:BaseListData):void {
_listData = DataGridListData(value);
}
private function onChange(event:Event):void {
data.vendorInvoiceNumber = invoiceNumberInput.text;
}
]]>
</mx:Script>
<mx:TextInput id="invoiceNumberInput"
width="95%"
change="onChange(event)"/>
</mx:HBox>
</mx:Component>
</mx:itemRenderer>
</mx:DataGridColumn>
<mx:DataGridColumn headerText="Vendor Invoice Date"
rendererIsEditor="true"
editorDataField="vendorInvoiceDate">
<mx:itemRenderer>
<mx:Component>
<mx:HBox width="100%" height="100%" horizontalAlign="center" verticalAlign="middle"
implements="mx.managers.IFocusManagerComponent">
<mx:Script>
<![CDATA[
import mx.events.CalendarLayoutChangeEvent;
[Bindable] public var vendorInvoiceDate:Date;
// Implements mx.managers.IFocusManagerComponent
override public function drawFocus(draw:Boolean):void {
vendorInvoiceDateInput.setFocus();
}
protected function onChange(event:CalendarLayoutChangeEvent):void {
data.vendorInvoiceDate = event.newDate;
}
]]>
</mx:Script>
<mx:DateField id="vendorInvoiceDateInput"
width="95%"
editable="true"
change="onChange(event)"/>
</mx:HBox>
</mx:Component>
</mx:itemRenderer>
</mx:DataGridColumn>
<mx:DataGridColumn editorDataField="isSelected"
headerText="Select"
rendererIsEditor="true">
<mx:itemRenderer>
<mx:Component>
<mx:HBox width="100%" height="100%" horizontalAlign="center" verticalAlign="middle"
implements="mx.controls.listClasses.IDropInListItemRenderer,mx.managers.IFocusManagerComponent">
<mx:Script>
<![CDATA[
import controller.PayablesController;
import mx.controls.dataGridClasses.DataGridListData;
import mx.controls.listClasses.BaseListData;
private var control:PayablesController = PayablesController.getInstance();
private var _listData:DataGridListData;
[Bindable] public var isSelected:Boolean;
override public function drawFocus(draw:Boolean):void {
selectionCheckBox.setFocus();
}
override public function get data():Object {
return super.data;
}
override public function set data(value:Object):void {
super.data = value;
selectionCheckBox.selected = data.isSelected
}
public function get listData():BaseListData {
return _listData;
}
public function set listData(value:BaseListData):void {
_listData = DataGridListData(value);
}
protected function onChange(event:Event):void {
data.isSelected = selectionCheckBox.selected;
control.updateBatchSelections();
}
]]>
</mx:Script>
<mx:CheckBox id="selectionCheckBox" change="onChange(event)"/>
</mx:HBox>
</mx:Component>
</mx:itemRenderer>
</mx:DataGridColumn>
</controls:columns>