ListboxField not showing selected values about silverstripe-widgets HOT 8 CLOSED

<?php

namespace Widgets\NewsUpdates;


use SilverStripe\Widgets\Model\Widget;
use SilverStripe\Forms\FieldList;
use SilverStripe\Forms\TextField;
use SilverStripe\Forms\TextareaField;
use SilverStripe\Forms\NumericField;
use SilverStripe\Forms\ListboxField;
use SilverStripe\ORM\ArrayList;
use SilverStripe\View\ArrayData;
use SilverStripe\Forms\HTMLEditor\HTMLEditorField;
use SilverStripe\Forms\DropdownField;

use News\NewsDetailPage;


class NewsUpdates extends Widget{
	private static $db = array(
		'WidgetTitle' => 'Varchar',
		'NewsPagesId_A'		=>	'Text',
		'WidgetWidth'   =>  'Varchar',
		'ViewAll'		=>	'Varchar'
	);
	private static $title = 'NewsUpdates HALF';
	private static $cmsTitle = 'NewsUpdates';
	private static $description = 'Description goes here';

	private static $many_many = [
		//'NewsPagesId' => NewsDetailPage::class,
	];

	public function getCMSFields(){
		$news_detail = NewsDetailPage::get()->map('ID','Title')->toArray();
		//print_r( $news_detail );
		//print_r($this->NewsPagesId_A);exit;
		//$news_detail = array("1"=>"one","2"=>"two","3"=>"three");


		$f = new FieldList(
			new TextField('WidgetTitle', 'Title'),
			new TextField('ViewAll', 'View all link'),
			ListboxField::create('NewsPagesId_A','Select newsfff',$news_detail),
			DropdownField::create('WidgetWidth','Widget Width',[
				'12'    =>  'FULL',
				'6'     =>  'HALF',
				'4'     =>  '1/3'
			])
		);
		return $f;
		
	}
	
}

private static $many_many = [
	'NewsPagesId' => NewsDetailPage::class,
];