download button - save file to disk instead of opening - php

Question

I have a download button and when i click on it, instead of saving to disk it opens it in the browser. I tried a bunch of attempts to make it open in the browser but it doesnt seem to do anything
<?php
// make a connection to the database
require_once("connection/connection.php");
//retrieve the ID from the url to fetch the specific details
if ($_GET['id'] != ""){
$item_id = $_GET['id'];
$bad_id = FALSE;
}
else{
$item_id = "";
$bad_id = TRUE;
}
//select the specific item from the database
// run if statement to ensure valid id was passed
if (is_numeric ($_GET['id'])){
$query = "SELECT name FROM repository WHERE item_id = '$item_id'";
$result = mysql_query($query) or die(mysql_error());
// assign the values to an array
$row = mysql_fetch_assoc($result);
//assign the values from the array to variables
$name = $row['name'];
}
// define path to the xml file
$file = "xml/".$hud_name . "_cfg.xml";
// check to make sure the file exists
if(!file_exists($file)){
die('Error: File not found.');
} else{
// Set headers
header("Content-Type: application/xml");
header("Content-Disposition:attachment; filename=".basename($file)."");
readfile($file);
}
?>
That is download.php and it obviously finds the file because it doesnt give the error about it not existing. It also echos back the correct file path
Then on another page i have:
<img src="images/download.png" alt=""/>
Any ideas whats wrong?

Answer 1

Well the solution turned out to be simple in the end but i didnt see any documentation saying the header must be the very first line. If i placed:
header("Content-Type: application/xml");
as the first line and then the coding below it and the other header info at the end it works. Im not sure if that's the solution or a workaround but it fixed it for me