What causes this: Using $this when not in object context - php

Question

Fatal error: Using $this when not in object context in plugins/newsarticles/controller/NewsArticleController.php on line 29
I can see where it is erroring, line 29 is this line:
$sqlFetch = $this->model->getAllNewsArticlesByDate();
Below I have submitted my code, can anyone shed any light on this?
<?php
require_once("plugins/newsarticles/model/NewsArticleDB.php");
class NewsArticleController
{
private $model;
public function __construct()
{
$this->model = new NewsArticleDB();
} //end constructor
/**
*Grab all the News Articles using the function
*Filter by date
*return the most recent 10
*/
function newsArticleHome()
{
//Grab the News Articles by date
$sqlFetch = $this->model->getAllNewsArticlesByDate();
foreach ($sqlFetch as $row)
{
//Insert posts into an object array
$objNewsArticle[] = new NewsArticle($row['newsId'],$row['newsTitle'], $row['newsPreview'], $row['newsDisplayPicture'], $row['newsContet']." ".$row['newsCategories'], $row['newsSubmissionDate']);
}
//Count the array incase it's less than 10 posts
//If it's more than 10, then set to 10, if it's less then set to x
if(count($objNewsArticle) > 10)
{
$tempObjectCount = 10;
}
else
{
$tempObjectCount = count($objNewsArticle);
}
//Store them in an array for output
for($tempLoopNumber = 0; $tempLoopNumber<$tempObjectCount; $tempLoopNumber++)
{
$recentNewsArticles[$tempLoopNumber] = $objNewsArticle[$tempLoopNumber];
}
return $recentNewsArticles;
}
function newsArticleId($id)
{
//Grab the Posts by date
$sqlFetch = $this->model->getAllNewsArticlesByDate();
$tempOptions = $sqlFetch->fetchAll();
$tempOpNumber = count($tempOptions);
for($tempNewsArticleNumber = 0; $tempNewsArticleNumber<$tempOpNumber; $tempNewsArticleNumber++)
{
if($tempOptions[$tempNewsArticleNumber]['newsId'] == $id)
{
$singlePost = $tempOptions[$tempNewsArticleNumber];
}
}
return $singlePost;
}
} //end class
?>
I am calling this from another file named testing:
include_once("plugins/newsarticles/controller/NewsArticleController.php");
echo "out";
echo NewsArticleController::newsArticleHome();

Answer 1

NewsArticleController::newsArticleHome(); is calling the function as if it were a static function. You need rather to create an instance of the class.
$nacont = new NewsArticleController();
$nacont->newsArticleHome();