Prevents error when item prop is not set

Allows setting custom value and defaultValue

assets/js/src/form/fields/text.jsx

@@ -2,9 +2,19 @@ import React from 'react';
 
 const FormFieldText = React.createClass({
   render() {
-    let value = this.props.item[this.props.field.name];
-    if (value === undefined) {
-      value = this.props.field.defaultValue || '';
+    const item = this.props.item || {};
+    let value;
+    let defaultValue;
+    // value should only be set when onChangeValue is configured
+    if (this.props.onValueChange instanceof Function) {
+      value = item[this.props.field.name];
+      // set value to defaultValue if available
+      value = (value === undefined && this.props.field.defaultValue) ?
+        this.props.field.defaultValue : value;
+    }
+    // defaultValue should only be set only when value is not set
+    if (!value && this.props.field.defaultValue) {
+      defaultValue = this.props.field.defaultValue;
     }
 
     return (
@@ -24,6 +34,7 @@ const FormFieldText = React.createClass({
         name={this.props.field.name}
         id={`field_${this.props.field.name}`}
         value={value}
+        defaultValue={defaultValue}
         placeholder={this.props.field.placeholder}
         onChange={this.props.onValueChange}
         {...this.props.field.validation}