如何从Bootstrap 4下拉项目菜单显示所选项目

Question

I'm trying to display what the user selects once they click on an item from the Boostrap 4 drop down menu.

Ex. "What is your eye color" User selects : Blue - Blue is displayed after click.

Ex. "What is your skin tone" User selects: Fair- Fair is displayed after click.

I have done research and jQuery seems to be the best bet however all of the solutions are for older bootstrap versions. I'm using Boostrap 4 and there are no li tags in the bootstrap 4 code, it's all a class tags so I'm not sure how to fit that into the jQuery option below. Also, I have (2) dropdown menus - please see pic. I'm not sure if this makes it more tricky. Any assistance or direction would be great.

jQuery:

$(document).ready (function(){

$('#selectmenu1 a').click(function){

}

HTML:

 <!--Drop down Item 1 -->
<h3 class="display-4" style="font-size: 1.5rem;">What is your eye color</h3>
<div class="dropdown">
  <button class="btn btn-info btn-md dropdown-toggle" type="button" id="dropdownMenuButton" data-toggle="dropdown" aria-haspopup="true" aria-expanded="false" style="background-color: #588c7e;">
    Eye Color
  </button>


  <div class="dropdown-menu" onchange="selectMenu1" aria-labelledby="dropdownMenuButton">
    <a class="dropdown-item" href="#" data="brown"><img src="img/brown_eye.jpg" class="rounded-circle"> Brown</a>
    <a class="dropdown-item" href="#" data="blue"><img src="img/blue_eye.jpg" class="rounded-circle" > Blue</a>
    <a class="dropdown-item" href="#" data="green"><img src="img/green_eye.jpg" class="rounded-circle" > Green</a>
    <a class="dropdown-item" href="#" data="hazel"><img src="img/hazel_eye.jpg" class="rounded-circle" > Hazel</a>
  </div>

</div>


<!--Drop down Item 2-->
<h3 class="display-4" style="font-size: 1.5rem;"> What is your skin tone</h3>
<div id="menu2" class="dropdown">
  <button class="btn btn-info btn-md dropdown-toggle" type="button" id="dropdownMenuButton" data-toggle="dropdown" aria-haspopup="true" aria-expanded="false" style="background-color: #588c7e;">
    Skin Tone
  </button>

  <div class="dropdown-menu" onchange="selectMenu2" aria-labelledby="dropdownMenuButton">
    <a class="dropdown-item" href="#" data="fair"><img src="img/fair.jpg" class="rounded-circle" > Fair (porcelain)</a>
    <a class="dropdown-item" href="#" data="light"><img src="img/light.jpg" class="rounded-circle" > Light (fair to light)</a>
    <a class="dropdown-item" href="#" data="medium"><img src="img/medium.jpg" class="rounded-circle" > Medium (light to medium)</a>
    <a class="dropdown-item" href="#" data="bronze"><img src="img/bronze_dark.jpg" class="rounded-circle" > Bronze dark (deep tan)</a>
    <a class="dropdown-item" href="#" data="tan"><img src="img/tan.jpg" class="rounded-circle" > Tan (warm to medium)</a>
    <a class="dropdown-item" href="#" data="rich"><img src="img/dark.jpg" class="rounded-circle" > Rich (deep)</a>
  </div>

</div>

<script>

    document.onreadystatechange = function () {
      if (document.readyState === "interactive") {
          initApplication();
      }
  }


  var eyeColor = null;
  function selectMenu1(value){
    eyeColor = value;
  }

  var skinTone = null;
  function selectMenu2(value){
    skinTone = value;
  }

  function validate()  { 
    if (eyeColor && skinTone){
      // alert(`You selected ${eyeColor} eye colour and ${skinTone} skin tone.`);

    if (eyeColor=="brown" && skinTone=="fair"){
      window.location = "brown/brown_fair.html";
    } else if (eyeColor=="brown" && skinTone=="light"){
      window.location = "brown/brown_light.html";
    } else if (eyeColor=="brown" && skinTone=="medium"){
      window.location = "brown/brown_medium.html";
    } else if (eyeColor=="brown" && skinTone=="bronze"){
      window.location = "brown/brown_bronze.html";
    } else if (eyeColor=="brown" && skinTone=="tan"){
      window.location = "brown/brown_tan.html";
    } else if (eyeColor=="brown" && skinTone=="rich"){
      window.location = "brown/brown_rich.html";
    }   

    if (eyeColor=="blue" && skinTone=="fair"){
      window.location = "blue/blue_fair.html";
    } else if (eyeColor =="blue" && skinTone=="light"){
      window.location = "blue/blue_light.html";
    } else if (eyeColor =="blue" && skinTone=="medium"){
      window.location = "blue/blue_medium.html";
    } else if (eyeColor =="blue" && skinTone=="bronze"){
      window.location = "blue/blue_bronze.html";
    } else if (eyeColor=="blue" && skinTone=="tan"){
      window.location = "blue/blue_tan.html";
    } else if (eyeColor=="blue" && skinTone=="rich"){
      window.location = "blue/blue_rich.html";
    }

    if (eyeColor=="green" && skinTone=="fair"){
        window.location = "green/green_fair.html";
    } else if (eyeColor == "green" && skinTone=="light"){
      window.location= "green/green_light.html";
    } else if (eyeColor== "green" && skinTone=="medium"){
      window.location="green/green_medium.html";
    } else if (eyeColor=="green" && skinTone=="bronze"){
      window.location="green/green_bronze.html";
    } else if (eyeColor=="green" && skinTone=="tan"){
      window.location="green/green_tan.html";
    } else if (eyeColor=="green" && skinTone=="rich"){
      window.location="green/green_rich.html";
    }


    if (eyeColor=="hazel" && skinTone=="fair"){
        window.location = "hazel/hazel_fair.html";
    } else if (eyeColor=="hazel" && skinTone=="light"){
      window.location="hazel/hazel_light.html";
    } else if (eyeColor=="hazel" && skinTone=="medium"){
      window.location="hazel/hazel_medium.html";
    } else if (eyeColor=="hazel" && skinTone=="bronze"){
      window.location="hazel/hazel_bronze.html";
    } else if (eyeColor=="hazel" && skinTone=="tan"){
      window.location="hazel/hazel_tan.html";
    } else if (eyeColor=="hazel" && skinTone=="rich"){
      window.location="hazel/hazel_rich.html";
    }
  }

    else if (!eyeColor){
      alert("Please pick an eye colour");
    } else if (!skinTone){
      alert("Please pick a skin tone");
    }
    }

  function initApplication(){
    //setup dropdown menu selection events
    Array.from(document.querySelectorAll(".dropdown-menu")).forEach((menu,idx)=>{
      const menuCallbackName = menu.attributes.onchange.value;
      const fetchedCallback = window[menuCallbackName] || null;

      if (fetchedCallback){
        Array.from(menu.children).forEach((child)=>{
          const callbackValue = child.attributes.data ? child.attributes.data.value : null;
          if (callbackValue) child.onclick = () => fetchedCallback(callbackValue);
        });
      } else console.error(`No callback function named ${menuCallbackName} for menu ${idx}`);

    });
  }
</script>

Answer 1

You can access the data using jQuery's "attr()" function.

$('#selectmenu1 a').click(
  function( event ){
    // Prevents browser from treating like normal anchor tag
    event.preventDefault()

    // Retrieves data in anchor tag
    let data = $(this).attr('data')
  }
)

Side note, it is possible to use list tags for this in Bootstrap. Bootstrap is really flexible and robust. Also, in my opinion, it would be most semantically correct to use "select".

Answer 2

I found the solution:

I included input-group into my html, as well as included jQuery:

HTML:

    <h3 class="display-4" style="font-size: 1.5rem;">What is your eye color</h3>
    <div class="dropdown">
        <div class="input-group justify-content-center">
            <div class="input-group-btn">
                <button class="btn btn-info btn-md dropdown-toggle" type="button" id="dropdownMenuButton" data-toggle="dropdown" aria-haspopup="true" aria-expanded="false" style="background-color: #588c7e;">
                    Eye Color

                </button>

                <div class="dropdown-menu" onchange="selectMenu1" aria-labelledby="dropdownMenuButton">
                    <a class="dropdown-item" href="#" data="brown" ><img src="img/brown_eye.jpg" class="rounded-circle"> Brown</a>
                    <a class="dropdown-item" href="#" data="blue" ><img src="img/blue_eye.jpg" class="rounded-circle" > Blue</a>
                    <a class="dropdown-item" href="#" data="green" ><img src="img/green_eye.jpg" class="rounded-circle" > Green</a>
                    <a class="dropdown-item" href="#" data="hazel" ><img src="img/hazel_eye.jpg" class="rounded-circle" > Hazel</a>
                </div>

            </div>
        </div>
    </div>



<script>
    $(".dropdown-menu a ").click(function(){
                $(this).parents(".input-group-btn").find('.btn').text($(this).text());
            });
</script>

Answer 3

And if even easier

<script>
$(".dropdown-menu a ").click(function () {
    let x = $(this).text();
    alert(x);
});
</script>

Works with this HTML below. No input-group needed and jQuery short enough.

<nav class="navbar navbar-light bg-light">
  <a class="navbar-brand" data-toggle="modal" href="#myModal">Navbar</a>
  <div class="dropdown">
    <button class="btn btn-primary dropdown-toggle" type="button" 
id="dropdownMenuButton" style="width:4rem"
            data-toggle="dropdown">en
    </button>
    <div class="dropdown-menu" id="dropDownMenu" aria- 
    labelledby="dropdownMenuButton">
      <a class="dropdown-item" href="#">en</a>
      <a class="dropdown-item" href="#">de</a>
    </div>
  </div>
</nav>