--- loncom/homework/response.pm	2014/08/28 14:41:18	1.236
+++ loncom/homework/response.pm	2014/09/24 18:14:27	1.237
@@ -1,7 +1,7 @@
 # The LearningOnline Network with CAPA
 # various response type definitons response definition
 #
-# $Id: response.pm,v 1.236 2014/08/28 14:41:18 raeburn Exp $
+# $Id: response.pm,v 1.237 2014/09/24 18:14:27 damieng Exp $
 #
 # Copyright Michigan State University Board of Trustees
 #
@@ -578,10 +578,15 @@ sub start_mathresponse {
 
 sub edit_mathresponse_button {
     my ($id,$field)=@_;
-    my $button=&mt('Edit Answer');
-#    my $helplink=&Apache::loncommon::help_open_topic('Formula_Editor');
-    my $iconpath=$Apache::lonnet::perlvar{'lonIconsURL'};
-    return(<<ENDFORMULABUTTON);
+    my $btype = $env{'browser.type'};
+    my $bversion = $env{'browser.version'};
+    if (($btype eq 'explorer' && $bversion < 9) || ($btype eq 'safari' && $bversion < 3) ||
+        ($btype eq 'mozilla' && $bversion < 3)) {
+      # DragMath applet
+      my $button=&mt('Edit Answer');
+#     my $helplink=&Apache::loncommon::help_open_topic('Formula_Editor');
+      my $iconpath=$Apache::lonnet::perlvar{'lonIconsURL'};
+      return(<<ENDFORMULABUTTON);
 <script type="text/javascript" language="JavaScript">
 function edit_${id}_${field} (textarea) {
     thenumber = textarea;
@@ -591,6 +596,27 @@ function edit_${id}_${field} (textarea)
 </script>
 <a href="javascript:edit_${id}_${field}('${field}');void(0);"><img class="stift" src="$iconpath/stift.gif" alt="$button" title="$button" /></a>
 ENDFORMULABUTTON
+      
+    } else {
+      # LON-CAPA math equation editor
+      return(<<EQ_EDITOR_SCRIPT);
+<script type="text/javascript">
+  var field = document.getElementById('${field}');
+  field.className += ' math'; // note the space
+  var LCMATH_started;
+  if (typeof LCMATH_started === 'undefined') {
+    LCMATH_started = true;
+    var script = document.createElement("script");
+    script.type = "text/javascript";
+    script.src = "/adm/LC_math_editor/LC_math_editor.min.js";
+    document.body.appendChild(script);
+    window.addEventListener('load', function(e) {
+        LCMATH.initEditors();
+    }, false);
+  }
+</script>
+EQ_EDITOR_SCRIPT
+    }
 }
 
 sub end_mathresponse {