Q:

Add Number on Button Click using jQuery?

I have a + and - button. I need to have them increase or decrease an input value based on the click. I have tried the following code: 
HTML
<label for="CAT_Custom_410672">Veloce</label>
<input type="text" class="cat_textbox" id="CAT_Custom_410672" name="CAT_Custom_410672" maxlength="4000" value="0" />
 <ul class="button-group button-click">
  <li><a href="#" class="small button secondary"><i class="fa fa-plus"><span class="hide">+</span></i></a></li>
  <li><a href="#" class="small button secondary"><i class="fa fa-minus"><span class="hide">-</span></i></a></li>
 </ul>

JS
$(function() {
$(".button-click").on("click", function() {

  var $button = $(this);
  var oldValue = $button.parent().find("input").val();

  if ($button.text() == "+") {
      var newVal = parseFloat(oldValue) + 1;
    } else {
   // Don't allow decrementing below zero
    if (oldValue > 0) {
      var newVal = parseFloat(oldValue) - 1;
    } else {
      newVal = 0;
    }
  }

  $button.parent().find("input").val(newVal);

})
});

How do I correct the script to function properly?
Note: No errors are thrown. It just doesn't work.

A:

The problem is that you are selecting .button-click and that's the class of the parent list
Try this:
$(function() {
$(".button-click a").on("click", function() {

  var $button = $(this);
  var oldValue = $button.closest("ul").prev().val();

  if ($button.text() == "+") {
      var newVal = parseInt(oldValue) +1;
    } else {
   // Don't allow decrementing below zero
    if (oldValue > 0) {
      var newVal = parseInt(oldValue - 1);
    } else {
      newVal = 0;
    }
  }
  $button.closest("ul").prev().val(newVal);
})
});

Working Example

