如何从angularjs html part n中获取参数，使用$ http.post函数处理它并返回结果

I've been scratching my brain for hours already, first
html part :

<div class="list">
  <a class="item item-text-wrap item-thumbnail-left" ng-repeat='x in MainResults' href="#/">
    <img data-ng-src="img({{x.ID}})" width="100%">
    <font size="2pt">{{x.post_title}}</font><br>
    <font size="2pt">{{x.post_date}}</font>
  </a>
</div> 

AngularJS part :

function GetMainPage() {
    $http.get("http://test.web.id/7291001/MainPage.php").
        success ( function(data) {
            $scope.MainResults = data;
        }
    );
};

$scope.img = function (NewsID) {
    $http.defaults.headers.post['Content-Type'] = 'application/x-www-form-urlencoded; charset=UTF-8';
    var postID = 'ID='+JSON.stringify (ID); 
    $http({
        method : 'POST',
        url : 'http://test.code.id/7291001/GetImage.php',
        data : postID,
        headers : {'Content-Type':'application/x-www-form-urlencoded; charset=UTF-8'}
    }).success(function(res) {
        console.log(res);
    }).error(function(error) {
        console.log(error);
    });    
};

The PHP Part :

header("Access-Control-Allow-Origin: *");

    $data = json_decode($_POST['ID']);
    //echo $data;

    //Keperluan Koneksi
    $database = "test_db";
    $hostname = "test.code.id";
    $username = "*****";
    $password = "*****";

    //Koneksi
    $db = new PDO("mysql:host=$hostname;dbname=$database", $username, $password, array(PDO::MYSQL_ATTR_INIT_COMMAND =>  'SET NAMES utf8'));

    //Query1
    $sql1 = "SELECT pict_url FROM wp_posts WHERE post_parent = '$data' AND post_type = 'attachment' AND post_mime_type = 'image/jpeg' ORDER BY post_date ASC LIMIT 0,1";
    $prep1 = $db->prepare($sql1);
    $prep1->execute();

    //Array Result 1
    $result1 = $prep1->fetchAll(PDO::FETCH_ASSOC);

    //JSON Result 1
    $json1 = json_encode($result1);
    echo $json1;

    $db = null; 

What I Actually trying to do is, grabbing pict_url from the ID i've grabbed from MainResults and displayed in my html part, but I Cannot to make it work, can someone help me with this ? The Database Connection is fine, but i cant figure out how angularjs should work.