symfony event listener on change

Question

My form contains a select field that contains two options: show and hide option: I want when I select the show option, a text field should be appear in the form and if I select hide option, the text field should be disappear (hidden).

I ask which method should be used, any one has an example how doing this?

Answer 1

You certainly need Javascript to achieve this. Very simple working example using jQuery :

$(function() {
  $('#type').change(function() {
    if ($('#type').val() == 'show') {
      $('#hidden_text').show();
    } else {
      $('#hidden_text').hide();
    }
  });
});

<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
Type
<select name="type" id="type" style="margin-left:57px; width:153px;">
  <option name="Show" value="show">Show</option>
  <option name="Hide" value="hide">Hide</option>
</select>

<div class="row" id="hidden_text">
  Hidden text
</div>

You may want to adapt this example to the ids used in your view so that the onChange event is triggered on your select field.