Input text Font color

programming flash
1

I am adding INPUTTEXT through actionscript

and want to change the text color through color picker component


var mainContainer:MovieClip = new MovieClip();
var fontsContainer:MovieClip;
fontColorPicker.addEventListener(ColorPickerEvent.CHANGE, changeFontColor);
 
function addTextonStage(event:MouseEvent):void
{
    var txtField:TextField = new TextField();
    txtField.type = TextFieldType.INPUT;
    
    txtField.defaultTextFormat = fmt;
    fmt.align = TextFormatAlign.LEFT;
    txtField.multiline = true;
    txtField.autoSize = TextFieldAutoSize.LEFT;
    txtField.antiAliasType = AntiAliasType.ADVANCED;
    txtField.wordWrap = true;
   
    fontsContainer = new MovieClip();
    fontsContainer.addChild(txtField);
    mainContainer.addChild(fontsContainer);
    fontsContainer.addEventListener(MouseEvent.MOUSE_DOWN, fl_ClickToDrag);
    
     
}
 
function changeFontColor(e:ColorPickerEvent):void  
{  
    fmt.color = fontColorPicker.selectedColor; 
    fontsContainer.txtField.defaultTextFormat = fmt;
    fontsContainer.txtField.setTextFormat(fmt);  
       
}

I am not able to get Font color change

ERRORS:

TypeError: Error #1009: Cannot access a property or method of a null object reference.
    at scrapBook_fla::MainTimeline/changeFontColor()
    at flash.events::EventDispatcher/dispatchEventFunction()
    at flash.events::EventDispatcher/dispatchEvent()
    at fl.controls::ColorPicker/onSwatchClick()

Following the tutorial , which changing color of inputtext on stage instance

http://active.tutsplus.com/tutorials/actionscript/develop-a-useful-fon t-picker-application-with-actionscript-30/