diff --git a/app/app.js b/app/app.js
index 4d84da6..b4773da 100644
--- a/app/app.js
+++ b/app/app.js
@@ -1,5 +1,95 @@
 'use strict'
 
+function getClassXMLDir(){
+  // // Use a real directory
+  // var classXMLDirValue = "'/home/walid/shared_on_wifi/xml/'"
+  // // Use null to be translated to None by the json parser
+  // // Follow https://docs.python.org/2/library/json.html#encoders-and-decoders
+  // classXMLDirValue = "null"
+
+  var classXMLDir = "";
+
+  var checkboxValue = document.getElementById('class_xml_dir_check').checked;
+  if (checkboxValue == true) {
+    var classXMLDirValue;
+
+    var textValue = document.getElementById('class_xml_dir_text').value;
+    if (textValue == '') {
+      classXMLDirValue = "null";
+    }
+    else {
+      classXMLDirValue = "\""+ textValue +"\"";
+    }
+
+    classXMLDir = '\"classXMLDir\":' + classXMLDirValue;
+  }
+
+  return classXMLDir;
+}
+
+function getClassXML(){
+  var classXML = "";
+
+  var checkboxValue = document.getElementById('class_xml_check').checked;
+  if (checkboxValue == true) {
+    var classXMLValue;
+
+    var textValue = document.getElementById('class_xml_text').value;
+    if (textValue == '') {
+      classXMLValue = "null";
+    }
+    else {
+      classXMLValue = "\""+ textValue +"\"";
+    }
+
+    classXML = '\"classXML\":' + classXMLValue;
+  }
+
+  return classXML;
+}
+
+function getNamespacePlaceholder(){
+  var namespacePlaceholder = "";
+
+  var checkboxValue = document.getElementById('namespace_placeholder_check').checked;
+  if (checkboxValue == true) {
+    var namespacePlaceholderValue;
+
+    var textValue = document.getElementById('namespace_placeholder_text').value;
+    if (textValue == '') {
+      namespacePlaceholderValue = "null";
+    }
+    else {
+      namespacePlaceholderValue = "\""+ textValue +"\"";
+    }
+
+    namespacePlaceholder = '\"NAMESPACE_PLACEHOLDER\":' + namespacePlaceholderValue;
+  }
+
+  return namespacePlaceholder;
+}
+
+function getOutputDir(){
+  var outputDir = "";
+
+  var checkboxValue = document.getElementById('output_dir_check').checked;
+  if (checkboxValue == true) {
+    var outputDirValue;
+
+    var textValue = document.getElementById('output_dir_text').value;
+    if (textValue == '') {
+      outputDirValue = "null";
+    }
+    else {
+      outputDirValue = "\""+ textValue +"\"";
+    }
+
+    outputDir = '\"OUTPUT_DIR\":' + outputDirValue;
+  }
+
+  return outputDir;
+}
+
 function attachDOMListeners(){
   document.getElementById('run_langform').addEventListener('click', () => {
     //langform_start
@@ -10,16 +100,21 @@ function attachDOMListeners(){
 
     var executablePath = "/home/walid/Documents/python_shell_simple_com/zmq_client";
 
-    // Use a real directory
-    var classXMLDirValue = "'/home/walid/shared_on_wifi/xml/'"
-    // Use null to be translated to None by the json parser
-    // Follow https://docs.python.org/2/library/json.html#encoders-and-decoders
-    classXMLDirValue = "null"
-
-    var classXMLDir = '\"classXMLDir\":' + classXMLDirValue +''
+    var classXMLDir = getClassXMLDir();
+    var classXML    = getClassXML();
+    var namespacePlaceholder = getNamespacePlaceholder();
+    var outputDir = getOutputDir();
 
     var settings =  "\"settings\": {"
-    settings += classXMLDir
+
+    if (classXMLDir != "" && classXML != "")
+      settings += classXMLDir + ", ";
+    if (classXML != "" && namespacePlaceholder != "")
+      settings += classXML + ", ";
+    if (namespacePlaceholder != "" && outputDir != "")
+      settings += namespacePlaceholder + ", ";
+    settings += outputDir;
+
     settings += "}"
 
     var msg = "{" + settings + "}"
@@ -29,7 +124,6 @@ function attachDOMListeners(){
 
     var parameters = ["--msg="+msg, "--localhost="+localhost, "--port="+port];
 
-
     console.log("Set to send: "+ msg +" over "+ localhost +":"+ port +".");
 
     var fs = require('fs');
diff --git a/index.html b/index.html
index 1685bf7..39b4c29 100644
--- a/index.html
+++ b/index.html
@@ -15,10 +15,30 @@
     <h3>Set Langform Settings and Run:</h3>
     <br>
     <div class="row">
-      <div class="five columns">
+      <div class="setting">
         <label for="classXMLDir">Class XML Dir</label>
-        <input class="u-full-width" placeholder="eg: /home/walid/tutorial/docs/xml" id="class_xml_dir" type="text">
+        <input type="checkbox" id="class_xml_dir_check" checked><label for="class_xml_dir_label"> Overwrite default </label>
+        <input type="text" id="class_xml_dir_text" class="u-full-width" placeholder="eg: /home/walid/tutorial/docs/xml" value="/home/walid/shared_on_wifi/xml/">
       </div>
+
+      <div class="setting">
+        <label for="classXMLDir">Class XML</label>
+        <input type="checkbox" id="class_xml_check" checked><label for="class_xml_label"> Overwrite default </label>
+        <input type="text" id="class_xml_text" class="u-full-width" placeholder="eg: /home/walid/tutorial/docs/xml/classEntry.xml" value="/home/walid/shared_on_wifi/classEntry.xml">
+      </div>
+
+      <div class="setting">
+        <label for="classXMLDir">Namespace placeholder</label>
+        <input type="checkbox" id="namespace_placeholder_check" checked><label for="namespace_placeholder_label"> Overwrite default </label>
+        <input type="text" id="namespace_placeholder_text" class="u-full-width" placeholder="eg: __ns__" value="__ns__">
+      </div>
+
+      <div class="setting">
+        <label for="classXMLDir">Output Directory</label>
+        <input type="checkbox" id="output_dir_check" checked><label for="output_dir_label"> Overwrite default </label>
+        <input type="text" id="output_dir_text" class="u-full-width" placeholder="eg: generated/" value="generated/">
+      </div>
+
       <div class="two columns">
         <label for="run langform" class="invisible"></label>
         <input class="button-primary" value="run" id="run_langform" type="button">