Uncaught TypeError: Cannot read property 'getElementsByTagName' of null
    at drawMessages (Functions.js:182)
    at TConnection.onTournamentLoaded [as onData] (lineupload.js:169)
    at TConnection.<anonymous> (Functions.js:86)
    at XMLHttpRequest.<anonymous> (Functions.js:276)

function drawMessages(o) {
        if(!o){
        //alert(xmlhttp.status);
        }else{
        var bRes = true;
        var messageContainer = document.getElementById('messageContainer');
        messageContainer.innerHTML = '';
        messages = o.getElementsByTagName('message');
        for (var i = 0; i < messages.length; i ++) {
            sheet = document.createElement('div');
            sheet.id = 'sheet' + (new Date()).getTime();
            sheet.className = 'sheet-'+messages[i].getAttribute('cls');
            shtext = document.createElement('div');
            shtext.className = 'sheet-text';
            shtext.innerHTML = STR[messages[i].firstChild.nodeValue] ? STR[messages[i].firstChild.nodeValue] : messages[i].firstChild.nodeValue;
            sheet.appendChild(shtext);
            
            messageContainer.appendChild(sheet);
            setTimeout('var ob = document.getElementById("'+sheet.id+'"); if (ob) ob.style.display = "none"; if (getLineup && getLineup()) getLineup().drawAll();', 4000);
            
            if (messages[i].getAttribute('cls') == 'exception') {
                bRes = false;
            }
        }
        
        return bRes;
        }
    }

TypeError: o is null[Więcej informacji]  lineupload.js:116:6
    onLineupsUpdate http://localhost/js/lineupload.js:116:6
    TConnection/this.oConn.onreadystatechange< http://localhost/js/Functions.js:86:6
    createMethodReference/<

<?php

define('GL_FUNC_LINEUP', 1);

function getLineupPlayers($sPlayers, $iIdKlub, $bWithReserve = false) {
    $aPlayers = unserialize(stripslashes($sPlayers));//print_r($aPlayers);
    $aPMod = array('B' => 'GK', 'O' => 'CB', 'P' => 'CM', 'N' => 'CF');
    //poczatki stref
    $aP = array('B' => array(0, 1), 'O' => array(2, 340), 'P' => array(341, 730), 'N' => array(731, 1000));
    $bGkSet = false;
    
    foreach ($aPlayers as $iKey => $aVal) {
        if ($aPlayerData = mysql_fetch_assoc(mysql_query('
            SELECT
                p.*
            FROM
                pilkarze AS p
            WHERE
                id = '.$aVal['id'].'
                AND (
                    id_klub = '.$iIdKlub.'
                    OR (
                        SELECT
                            COUNT(id)
                        FROM
                            powolania
                        WHERE
                            id_klub = '.$iIdKlub.'
                            AND id=p.id
                    ) =  1
                )
        '))) {
            $aPlayers[$iKey]['data'] = $aPlayerData;
            if ($aVal['reserve']) {
                $aPlayers[$iKey]['position'] = $aPMod[$aPlayerData['pozycja']];
                if (!$bWithReserve) {
                    unset($aPlayers[$iKey]);
                }
            } else {
                if (!$aPlayers[$iKey]['position'] or $aPlayers[$iKey]['position'] == 'undefined') {
                    foreach ($aP as $sPos => $aPosRange) {
                        if ($aVal['x'] >= $aPosRange[0] and $aVal['x'] <= $aPosRange[1]) {
                            $aPlayers[$iKey]['position'] = $aPMod[$sPos];
                        }
                    }
                }
                if ($aPlayers[$iKey]['position'] == 'GK') {
                    $bGkSet = true;
                    $aPlayers[$iKey]['x'] = 0;
                    $aPlayers[$iKey]['y'] = 250;
                }
            }
        } else {
            unset($aPlayers[$iKey]);
        }
    }
        
    if (!$bGkSet) {
        foreach ($aPlayers as $iKey => $aVal) {
            $aPlayers[$iKey]['position'] = 'GK';
            $aPlayers[$iKey]['x'] = 0;
            $aPlayers[$iKey]['y'] = 250;
            break;
        }
    }print_r($aPlayers);
    return print_r('xxxsadsaxx');
}

define('ZONE_GK', 0);
define('ZONE_DEF', 1);
define('ZONE_MID', 2);
define('ZONE_FED', 3);

function getZone($p, $bAsString)
{
    $aZones = array();
    $aZones['GK'] = ZONE_GK;
    $aZones['CB'] = ZONE_DEF;
    $aZones['LB'] = ZONE_DEF;
    $aZones['SB'] = ZONE_DEF;
    $aZones['RB'] = ZONE_DEF;
    $aZones['CM'] = ZONE_MID;
    $aZones['LM'] = ZONE_MID;
    $aZones['RM'] = ZONE_MID;
    $aZones['SM'] = ZONE_MID;
    $aZones['OM'] = ZONE_MID;
    $aZones['DM'] = ZONE_MID;
    $aZones['CF'] = ZONE_FED;
    if ($bAsString)
    {
        $aStrings = array('B', 'O', 'P', 'N');
        return $aStrings[$aZones[$p]];
    }
    else
        return $aZones[$p];
}

?>