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javascriptevent-handlingdom-eventsevent-delegationdebouncing

Fire event on radio group after some time delay


I am searching for a solution to let an event fire on a radio group after some time delay.

Specifically, I need to ask users a question and want to submit their input without having the users click a separate button. At the same time, it shall be possible that the user clicks different radio buttons while considering the answer.

onInput and onChange are both fired immediately after a user click. However, is there another solution?

Here is small example:

<div class="form-check form-check-inline"> 
  <label> What is 17 * 21? </label>
  <br></br>      
  
  <input class="form-check-input" type="radio" id="MC_0" name="MC_first" value="1" oninput="console.log('here');">
  <label for="MC_0" class="form-check-label">263</label>

  <input class="form-check-input" type="radio" id="MC_1" name="MC_first" value="2" oninput="console.log('here');">
  <label for="MC_1" class="form-check-label">357</label>
</div>

I would love to have oninput only fire after, say, 5 seconds without activity in this radio group.


Solution

  • The OP needs to choose an approach which combines event-delegation and thedebounced handling of a callback-function.

    The requirements are that a (or each in case of more than just one) radio-group needs to be entirely nested within a parent-structure where the event-delegation takes place. And each delegation-node of cause needs to have its own debounced event-handler registered to its related input-event.

    Additionally a refactoring of the OP's markup is strongly recommended.

    function handleRadioGroupInput(evt) {
      const { target } = evt;
    
      console.log({ target });
    }
    
    document
      .querySelectorAll('fieldset')
      .forEach(elmNode =>
        elmNode
          // each radio-group parent has to register its own debounced handler.
          .addEventListener('input', _.debounce(handleRadioGroupInput, 3000))
      );
    body { margin: 0; }
    fieldset { float: left; width: 40%; }
    .as-console-wrapper { max-height: 140px!important; }
    <script src="https://cdnjs.cloudflare.com/ajax/libs/lodash.js/4.17.21/lodash.min.js"></script>
    
    <fieldset class="form-check form-check-inline">
      <legend> What is 17 * 21? </legend>
    
      <input class="form-check-input" type="radio" id="MC_0" name="MC_first" value="1">
      <label for="MC_0" class="form-check-label">263</label>
    
      <input class="form-check-input" type="radio" id="MC_1" name="MC_first" value="2">
      <label for="MC_1" class="form-check-label">357</label>
    </fieldset>
    
    <fieldset class="form-check form-check-inline">
      <legend> What is 7 * 22? </legend>
    
      <input class="form-check-input" type="radio" id="MC_2" name="MC_second" value="1">
      <label for="MC_2" class="form-check-label">154</label>
    
      <input class="form-check-input" type="radio" id="MC_3" name="MC_second" value="2">
      <label for="MC_3" class="form-check-label">144</label>
    </fieldset>