not use json.parse json.stringify for generation button action

gadget_json_generated_form.js

@@ -119,11 +119,14 @@
         div_input.appendChild(input);
 
         input = document.createElement("button");
-        input.value = btoa(JSON.stringify(json_field.patternProperties['.*']));
         input.setAttribute("class", "add-sub-form");
         input.type = "button";
         input.name = path;
         input.textContent = "Add";
+        gadget.props.add_buttons.push({
+          element: input,
+          schema_part: json_field.patternProperties['.*']
+        });
         div_input.appendChild(input);
 
         div.appendChild(div_input);
@@ -274,8 +277,9 @@
     return gadget.processValidation(json_url);
   }
 
-  function addSubForm(g, element) {
-    var subform_json = JSON.parse(atob(element.value)),
+  function addSubForm(g, options) {
+    var element = options.element,
+      subform_json = options.schema_part,
       input_text = element.parentNode.querySelector("input[type='text']"),
       div = document.createElement("div"),
       label;
@@ -301,7 +305,7 @@
   function loadEventList(gadget) {
     var g = gadget,
       field_list = g.props.inputs,
-      button_list = g.element.querySelectorAll('button.add-sub-form'),
+      button_list = g.props.add_buttons,
       label_list = g.element.querySelectorAll('label.slapos-parameter-dict-key'),
       i,
       promise_list = [];
@@ -317,7 +321,7 @@
 
     for (i = 0; i < button_list.length; i = i + 1) {
       promise_list.push(loopEventListener(
-        button_list[i],
+        button_list[i].element,
         'click',
         false,
         addSubForm.bind(g, g, button_list[i])
@@ -401,7 +405,8 @@
     .declareMethod('renderParameterForm', function (schema, default_dict) {
       var g = this,
         parent_element = document.createDocumentFragment();
-      g.params.inputs = [];
+      g.props.inputs = [];
+      g.props.add_buttons = [];
       render_subform(g, schema, default_dict, parent_element);
       while (g.element.firstChild) {
         g.element.removeChild(g.element.firstChild);