Tuesday 11 June 2019

Deselecting all options in HTML SELECT using Jquery plugin

I created my first jQuery plugin today. This plugin will deselect all select option elements after a given timeout when checking an associated checkbox which will in our plugin represent the $(this) object. It can be utilized when you use the data-target attribute. The data-target attribute will automatically select the first option when the checkbox is unchecked. This plugin, however - deselects all options after a given timeout of milliseconds using the setTimeout function. It will keep a pointer to the select object by applying the $() function on a passed in DOM element identifier. Example usage:
     <script type="text/javascript">
                $(function() {
                    $("[name=@SearchParametersDataContract.SomeDOMElementCheckbox]").deselectAfterSelectCheckbox("#@SomeDOMElementSelect",100);
                });
            </script>
The jQuery plugin looks like this:

        <script type="text/javascript">
            $.fn.deselectAllAfterUnselectCheckbox= function(targetSelect, timeout) {
                $(this).on("click",
                    function() {
                        if (timeout === null || timeout == undefined)
                            timeout = 50;
                        $targetSelect = $(targetSelect);
                        if (this.checked === false) {
                            setTimeout(function() {
                                 $targetSelect.children("option").attr("selected", false);
                            }, timeout)
                        };
                    });
            }
        </script>

Wednesday 5 June 2019

Random selection of a HTML SELECT element

Just made a JsFiddle of a random selection control for HTML SELECT tag. The JsFiddle is available here: Random selecting combobox (JsFiddle)
  • The control should use Bootstrap to function properly. It needs jQuery library for Javascript bit.
  • To turn on hiding the selected option, set the data-hide-selectedoption HTML 5 data attribute to "true".

Random selecting HTML SELECT control


<!-- 
  Bootstrap docs: https://getbootstrap.com/docs
-->

<div class="container">

  <div class="input-group mb-3">
    <div class="input-group-prepend">
      <span class="input-group-text" id="basic-addon1"><img style="cursor:pointer" title="Choose random value" alt="Choose random value" width="24" height="24" src="https://cdn4.iconfinder.com/data/icons/ionicons/512/icon-shuffle-512.png" /></span>
    </div>
    <select data-hide-selectedoption="true" disabled id="ComboBoxIceCreamBar" class="form-control" placeholder="Username" aria-label="Username" aria-describedby="basic-addon1">
 <option selected hidden>Choose icecream</option>
 <option value="Vanilla">Vanilla</option>
 <option value="Strawberry">Strawberry</option>
 <option value="Pineapple">Pineapple</option>
 <option value="Mint chocolate">Mint chocolate</option>
 <option value="Mango ice cream">Mango ice cream</option>
 <option value="Rasperry Ripple">Raspberry Ripple</option>
 <option value="Pistachio">Pistachio</option>
 <option value="Cookie dough">Cookie dough</option>
 <option value="Lemon">Lemon</option>
 <option value="Mango">Mango</option>
 </select>
    <!-- <input type="text" class="form-control" placeholder="Username" aria-label="Username" aria-describedby="basic-addon1"> -->
  </div>

</div>

<script type="text/javascript">
  $("#basic-addon1").on("click", function() {
    var selectcontrol = $(this).parent().siblings('select:first');
    var optionslength = selectcontrol.children('option').length;
    var randomIndex = Math.max(1, parseInt(Math.random() * optionslength));
  var optionElementToSelect = selectcontrol.children('option')[randomIndex];
    optionElementToSelect.selected = true;
  //debugger
  if (selectcontrol.data('hide-selectedoption')){
       optionElementToSelect.innerText = 'Selected value hidden.';   
  } 
  console.log("Selected ice cream: " + selectcontrol.val());
  });

</script>