Invalid argument supplied for foreach() FPDF PHP

Question

Here's the code for generating a PDF Table but it seems my code is not right regarding in foreach, the tutorial use file.txt. Guys its my first time using FPDF in php so i'm confused right now what i need to do with my error. Tutorials > Tutorial 4: Multi-columns FPDF Link

<?php
require('fpdf.php');
$hostname = "localhost";
$database = "brm_dbs";
$username = "root";
$password = "";
$conn = mysql_connect($hostname, $username, $password) or die(mysql_error());
mysql_select_db($database, $conn);
class PDF extends FPDF
{
// Load data
function LoadData($query)
{
    // Read file lines
    //$lines = file($file);
    //$lines = file($query);
    $result = mysql_query($query);
    $data = array();
    foreach($result as $line)
        $data[] = explode(',',trim($line));
    return $data;
}

// Simple table
function BasicTable($header, $data)
{
    // Header
    foreach($header as $col)
        $this->Cell(40,7,$col,1);
    $this->Ln();
    // Data
    foreach($data as $row)
    {
        foreach($row as $col)
            $this->Cell(40,6,$row,1);
        $this->Ln();
    }
}

// Better table
function ImprovedTable($header, $data)
{
    // Column widths
    $w = array(40, 35, 40, 45);
    // Header
    for($i=0;$i<count($header);$i++)
        $this->Cell($w[$i],7,$header[$i],1,0,'C');
    $this->Ln();
    // Data
    foreach($data as $row)
    {
        $this->Cell($w[0],6,$row[0],'LR');
        $this->Cell($w[1],6,$row[1],'LR');
        $this->Cell($w[2],6,$row[2],'LR',0,'R');
        $this->Cell($w[3],6,$row[3],'LR',0,'R');
        $this->Ln();
    }
    // Closing line
    $this->Cell(array_sum($w),0,'','T');
}

// Colored table
function FancyTable($header, $data)
{
    // Colors, line width and bold font
    $this->SetFillColor(255,0,0);
    $this->SetTextColor(255);
    $this->SetDrawColor(128,0,0);
    $this->SetLineWidth(.3);
    $this->SetFont('','B');
    // Header
    $w = array(40, 35, 40, 45);
    for($i=0;$i<count($header);$i++)
        $this->Cell($w[$i],7,$header[$i],1,0,'C',true);
    $this->Ln();
    // Color and font restoration
    $this->SetFillColor(224,235,255);
    $this->SetTextColor(0);
    $this->SetFont('');
    // Data
    $fill = false;
    foreach($data as $row)
    {
        $this->Cell($w[0],6,$row[0],'LR',0,'L',$fill);
        $this->Cell($w[1],6,$row[1],'LR',0,'L',$fill);
        $this->Cell($w[2],6,$row[2],'LR',0,'R',$fill);
        $this->Cell($w[3],6,$row[3],'LR',0,'R',$fill);
        $this->Ln();
        $fill = !$fill;
    }
    // Closing line
    $this->Cell(array_sum($w),0,'','T');
}
}


//Create new pdf file

//Select the Products you want to show in your PDF file
$query=("SELECT name,service,type,status FROM permits");


//$name = $row['name'];
//$service = $row['service'];
//$type = $row['type'];
//$status = $row['status'];
$pdf = new PDF();
// Column headings
$header = array('Resident', 'Frontline Service', 'Type', 'Status');
// Data loading
$data = $pdf->LoadData($query);
$pdf->SetFont('Arial','',14);
$pdf->AddPage();
$pdf->BasicTable($header,$data);
$pdf->AddPage();
$pdf->ImprovedTable($header,$data);
$pdf->AddPage();
$pdf->FancyTable($header,$data);


$pdf->Output();
?>

Warning: Invalid argument supplied for foreach() in C:\xampp\htdocs\project\heldeskback\sample_pdf3.php on line 19 FPDF error: Some data has already been output, can't send PDF file