i m just not able to solve this error… any help will be highly appreciated.

<![CDATA[
import mx.collections.ArrayCollection;
import mx.controls.dataGridClasses.DataGridColumn;
import mx.events.ListEvent;
import mx.formatters.DateFormatter;
import mx.rpc.events.ResultEvent;

[Bindable]
private var dataFields:ArrayCollection;

[Bindable]
private var dataProvider:ArrayCollection;

[Bindable]
private var selectedViewIndex:int = 0;

[Bindable]
private var _selectedIndex:Number = -1;

[Bindable]
private var addingRecord:Boolean;

private var dateFormatter:DateFormatter;

private const strNEW:String = "New";
private const ADD:String = "Add";

override protected function onResultHttpService(e:ResultEvent):void
{
dateFormatter = new DateFormatter();
dateFormatter.formatString = "MM/DD/YY";

var a:Array = xmlListToObjectArray(e.result.item);
dataProvider = new ArrayCollection(a);

// Get the values from properties XML.
a = properties.@dataFields.toString().split(",");
dataFields = new ArrayCollection(a);

var labels:Array = properties.@labels.toString().split(",");
field0Label.text = labels[0];
field1Label.text = labels[1];
field2Label.text = labels[2];

selectedIndex = 0;

if (properties.@selectedViewIndex.toString() != null&&
Number(properties.@selectedViewIndex) < (viewStack.numChildren – 1)) // Make sure the index is in range.
selectedViewIndex = Number(properties.@selectedViewIndex);
}

private function set selectedIndex(n:Number):void
{
addingRecord = false;

// Make sure we are within range of dataProvider.
if (n (dataProvider.length – 1))
n = 0;

var item:Object = dataProvider.getItemAt(n);
field0Input.text = item[dataFields[0]];
field1Input.selectedDate = item[dataFields[1]];
field2Input.text = item[dataFields[2]];

_selectedIndex = n;

indexInput.text = String(n + 1);
}

private function get selectedIndex():Number
{
return _selectedIndex;
}

private function onClickDeleteButton():void
{
dataProvider.removeItemAt(_selectedIndex);

if (dataProvider.length > 0)
selectedIndex = _selectedIndex;
}

private function saveData():void
{
var selectedItems:Object = dataProvider.getItemAt(_selectedIndex);
selectedItems[dataFields[0]] = field0Input.text;
selectedItems[dataFields[1]] = field1Input.selectedDate;
selectedItems[dataFields[2]] = field2Input.text;
}

private function onClickNewButton(e:MouseEvent):void
{
if (addingRecord) // Add the new record to dataProvider
{
// Generic object since the data field names are dictated by the xml.
var o:Object = new Object();
o[dataFields[0]] = field0Input.text;
o[dataFields[1]] = field1Input.selectedDate;
o[dataFields[2]] = field2Input.text;
dataProvider.addItem(o);
selectedIndex = dataProvider.length – 1;
addingRecord = false;
}
else // Clear out the fields for input.
{
field0Input.text = field1Input.text = field2Input.text = indexInput.text = “”;
addingRecord = true;
}
}

private function formatDate(item:Object, column:DataGridColumn):String
{
return dateFormatter.format(item[column.dataField]);
}

private function onChangeComboBox(e:ListEvent):void
{
saveData();

var index:int = ComboBox(e.target).selectedIndex
selectedViewIndex = index;
dispatchViewStackChange(index);
}

]]>

0}”
styleName=”leftArrowButton”
click=”saveData();selectedIndex-=1;” >

0}”
enter=”saveData();selectedIndex=Number(TextInput(event.currentTarget).text)-1;”
width=”30″/>

0}”
styleName=”rightArrowButton”
click=”saveData();selectedIndex+=1;”>

0}”
label=”Delete”
width = “65″
click=”onClickDeleteButton()”>

and i get the following error… pls help.

TypeError: Error #1009: Cannot access a property or method of a null object reference.
at com.esria.samples.dashboard.view::FormContent/saveData()[C:\Documents and Settings\testing\Desktop\flexProjects\dashboard\src\com\esria\samples\dashboard\view\FormContent.mxml:95]
at com.esria.samples.dashboard.view::FormContent/onChangeComboBox()[C:\Documents and Settings\testing\Desktop\flexProjects\dashboard\src\com\esria\samples\dashboard\view\FormContent.mxml:128]
at com.esria.samples.dashboard.view::FormContent/___FormContent_ComboBox1_change()[C:\Documents and Settings\testing\Desktop\flexProjects\dashboard\src\com\esria\samples\dashboard\view\FormContent.mxml:143]
at flash.events::EventDispatcher/dispatchEventFunction()
at flash.events::EventDispatcher/dispatchEvent()
at mx.core::UIComponent/dispatchEvent()[E:\dev\gumbo_beta2\frameworks\projects\framework\src\mx\core\UIComponent.as:11749]
at mx.controls::ComboBox/dispatchChangeEvent()[E:\dev\gumbo_beta2\frameworks\projects\framework\src\mx\controls\ComboBox.as:1882]
at mx.controls::ComboBox/close()[E:\dev\gumbo_beta2\frameworks\projects\framework\src\mx\controls\ComboBox.as:1629]
at mx.controls::ComboBox/dropdown_changeHandler()[E:\dev\gumbo_beta2\frameworks\projects\framework\src\mx\controls\ComboBox.as:2140]
at flash.events::EventDispatcher/dispatchEventFunction()
at flash.events::EventDispatcher/dispatchEvent()
at mx.core::UIComponent/dispatchEvent()[E:\dev\gumbo_beta2\frameworks\projects\framework\src\mx\core\UIComponent.as:11749]
at mx.controls.listClasses::ListBase/mouseUpHandler()[E:\dev\gumbo_beta2\frameworks\projects\framework\src\mx\controls\listClasses\ListBase.as:10156]
at mx.controls::List/mouseUpHandler()[E:\dev\gumbo_beta2\frameworks\projects\framework\src\mx\controls\List.as:2474]