Quantity selector

index.html

<section class="container">
  <div class="product-quantity">
    <h3>Quantity</h3>
    <input data-min="1" data-max="0" type="text" name="quantity" value="1" readonly="true"><div class="quantity-selectors-container">
      <div class="quantity-selectors">
        <button type="button" class="increment-quantity" aria-label="Add one" data-direction="1"><span>&#43;</span></button>
        <button type="button" class="decrement-quantity" aria-label="Subtract one" data-direction="-1" disabled="disabled"><span>&#8722;</span></button>
      </div>
    </div>
  </div>
</section>

quantity-selector.markdown

Quantity selector

A Pen by Chris Jones on CodePen.

License.

script.js

$("button").on("click", function(ev) {
  var currentQty = $('input[name="quantity"]').val();
  var qtyDirection = $(this).data("direction");
  var newQty = 0;
  
  if (qtyDirection == "1") {
    newQty = parseInt(currentQty) + 1;
  }
  else if (qtyDirection == "-1") {
    newQty = parseInt(currentQty) - 1;
  }

  // make decrement disabled at 1
  if (newQty == 1) {
    $(".decrement-quantity").attr("disabled", "disabled");
  }
  
  // remove disabled attribute on subtract
  if (newQty > 1) {
    $(".decrement-quantity").removeAttr("disabled");
  }
  
  if (newQty > 0) {
    newQty = newQty.toString();
    $('input[name="quantity"]').val(newQty);
  }
  else {
    $('input[name="quantity"]').val("1");
  }
});

scripts

<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.1.1/jquery.min.js"></script>

style.css

html {
  font-size: 16px; 
  margin: 0;
  padding: 0;
}

body {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif, "Apple Color Emoji", "Segoe UI Emoji", "Segoe UI Symbol";
}

.container {
  margin: 0;
  padding: 0;
  width: 100vw;
  height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
}

h3 {
  display: block;
  font-size: 0.6rem;
  font-family: sans-serif;
  text-transform: uppercase;
  letter-spacing: 0.05rem;
  margin-bottom: 0.25rem;
  color: #333;
}

.product-quantity {
  width: 10rem;
  display: block;
}

input {
  max-width: 2rem;
  margin: 0;
  padding: 0.75rem 0;
  text-align: center;
  border-top: 1px solid grey;
  border-left: 1px solid grey;
  border-bottom: 1px solid grey;
  border-right: 0;
}

.quantity-selectors-container {
  display: inline-block;
  vertical-align: top;
  margin: 0;
  padding: 0;
}

.quantity-selectors {
  display: flex;
  flex-direction: column;
  margin: 0;
  padding: 0;
}

.quantity-selectors button {
  -webkit-appearance: none;
  appearance: none;
  margin: 0;
  border-radius: 0;
  border: 1px solid grey;
  background-color: #fff;
  color: grey;
}

.quantity-selectors button:first-child {
  border-bottom: 0;
}

.quantity-selectors button:hover {
  cursor: pointer;
}

.quantity-selectors button[disabled="disabled"] {
  cursor: not-allowed;
}

.quantity-selectors button[disabled="disabled"] span {
  opacity: 0.5;
}