skins/common/preview.js

   1 // Live preview
   2
   3 function openXMLHttpRequest() {
   4         if( window.XMLHttpRequest ) {
   5                 return new XMLHttpRequest();
   6         } else if( window.ActiveXObject && navigator.platform != 'MacPPC' ) {
   7                 // IE/Mac has an ActiveXObject but it doesn't work.
   8                 return new ActiveXObject("Microsoft.XMLHTTP");
   9         } else {
  10                 return null;
  11         }
  12 }
  13
  14 /**
  15  * Returns true if could open the request,
  16  * false otherwise (eg no browser support).
  17  */
  18 function livePreview(target, text, postUrl) {
  19         prevTarget = target;
  20         if( !target ) {
  21                 window.alert('Live preview failed!\nTry normal preview.');
  22                 var fallback = document.getElementById('wpPreview');
  23                 if ( fallback ) { fallback.style.display = 'inline'; }
  24         }
  25         prevReq = openXMLHttpRequest();
  26         if( !prevReq ) return false;
  27
  28         prevReq.onreadystatechange = updatePreviewText;
  29         prevReq.open("POST", postUrl, true);
  30
  31         var postData = 'wpTextbox1=' + encodeURIComponent(text);
  32         prevReq.setRequestHeader("Content-Type", "application/x-www-form-urlencoded");
  33         prevReq.send(postData);
  34         return true;
  35 }
  36
  37 function updatePreviewText() {
  38         if( prevReq.readyState != 4 ) {
  39                 return;
  40         }
  41         if( prevReq.status != 200 ) {
  42                 window.alert('Failed to connect: ' + prevReq.status +
  43                         ' "' + prevReq.statusText + '"');
  44                 var fallback = document.getElementById('wpPreview');
  45                 if ( fallback ) { fallback.style.display = 'inline'; }
  46                 return;
  47         }
  48         prevTarget.innerHTML = prevReq.responseText;
  49
  50         /* Hide the active diff if it exists */
  51         var diff = document.getElementById('wikiDiff');
  52         if ( diff ) { diff.style.display = 'none'; }
  53 }