var pobrany = false;

function show(val)
{
  switch(val){
    case 1:
      var url = "http://localhost/art1.html";
      break;
    case 2:
      var url = "http://localhost/art2.html";
      break;
    case 3:
      var url = "http://localhost/art3.html";
      break;
    default:
      alert("Nie ma takiego artykułu.");
      return;
  }  
  var btn1 = document.getElementById("btn1");
  var btn2 = document.getElementById("btn2");
  var btn3 = document.getElementById("btn3");
  
  btn1.disabled = true;
  btn2.disabled = true;
  btn3.disabled = true;
  
  var dataDiv = document.getElementById("dataDiv");
  dataDiv.innerHTML = "Trwa ładowanie danych...";
  
  pobrany = false;
  startGETRequest(url, onComplete, onEnd);
}

function onComplete(responseText, responseXML)
{
  var dataDiv = document.getElementById("dataDiv");
  dataDiv.innerHTML = responseText;
  pobrany = true;
}

function onEnd()
{
  var btn1 = document.getElementById("btn1");
  var btn2 = document.getElementById("btn2");
  var btn3 = document.getElementById("btn3");
  btn1.disabled = false;
  btn2.disabled = false;
  btn3.disabled = false;
  if(!pobrany){
    var dataDiv = document.getElementById("dataDiv");
    dataDiv.innerHTML = "Wybrany artykuł nie jest dostępny.";
  }
}
