将旧值作为“ghost”拇指添加到滑块

I've styled a regular range slider using an example from w3schools. My goal is to send out a new value command to an external MQTT-based smarthome thing and show the old value as some kind of ghost-thumb first:

我使用w3schools的一个例子设计了常规范围滑块。我的目标是向外部基于MQTT的智能家居事物发送一个新的值命令,并将旧值显示为某种幽灵拇指:

After the smarthome system confirms the new value, the bubble will be removed - but that's not my problem at this point. I would like to place the ghost between the background of the slider and the real-value-thumb, currently it looks like this:

智能家居系统确认新值后,泡泡将被删除 - 但这不是我的问题。我想把幽灵放在滑块的背景和真值拇​​指之间,目前它看起来像这样:

Here you can see the result on JSFiddle, here's the code:

在这里你可以看到JSFiddle上的结果,这里是代码:

$('#slider_1').data('last-mqtt-value', 0.5);

$('#slider_1').on('input', function() {
  // Show ghost slider
  $('#slider_1_companion').css('left', 'calc('+ $(this).data('last-mqtt-value') / $(this).attr('max') +'* (100% - 20px))');
  $('#slider_1_companion').css('display', 'block');
});

$('#slider_1').on('change', function() {
  console.log( $(this).data('last-mqtt-value'), $(this).val() );

	// Simulate new input value incoming
  ///*
  setTimeout(() => {
    $(this).data('last-mqtt-value', $(this).val());
    $('#slider_1_companion').css('display', 'none');
  },5000);
  // */
});

.slider {
    -webkit-appearance: none;
    width: 100%;
    height: 10px;
    border-radius: 5px;   
    background: #ccc;
    outline: none;
}

.slider::-webkit-slider-thumb {
    -webkit-appearance: none;
    appearance: none;
    width: 20px;
    height: 20px;
    border-radius: 50%; 
    background: #6c757d;
    cursor: pointer;
    z-index: 5;
}

.slider::-moz-range-thumb {
    width: 20px;
    height: 20px;
    border-radius: 50%;
    background: #6c757d;
    cursor: pointer;
    z-index: 5;
}
/*https://*.com/a/46318225/1997890*/
.slider_wrapper {
    position: relative;
    width: 150px;
}
.slider_companion {
    background-color: #ccc;
    border-radius: 50%;
    width: 20px;
    height: 20px;
    position: absolute;
    top: calc(100% - 19px); /* for some reason this is not 20px (height of thumb) */
    /* left: calc( PERCENTAGE * (100% - 20px)); /* add this line dynamically via jQuery */
    display: none;
    pointer-events: none; /*click-through*/
}

<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>

<div id="slider_1_wrapper" class="slider_wrapper">
  <div id="slider_1_companion" class="slider_companion"></div>
  <input type="range" id="slider_1" class="slider" min="0" max="1.0" step="any">
</div>

1 个解决方案

#1

I would consider a box-shadow for the slider that you can adjust with CSS variable and no need for extra element and you will have the expected result.

我会考虑滑块的盒子阴影,您可以使用CSS变量调整,不需要额外的元素,您将获得预期的结果。

Here is an idea:

这是一个想法:

$('#slider_1').data('last-mqtt-value', 0.5);

$('#slider_1').on('input', function() {
  document.getElementById('slider_1_wrapper').style.setProperty("--c", 
  ($(this).data('last-mqtt-value') -  $(this).val() )*130 + 'px');
  /*130 = 150 - 20 = width of wrapper - width of thumb*/
  
});

$('#slider_1').on('change', function() {
   console.log( $(this).data('last-mqtt-value'), $(this).val() );

	// Simulate new input value incoming
  ///*
  setTimeout(() => {
    $(this).data('last-mqtt-value', $(this).val());
    document.getElementById('slider_1_wrapper').style.setProperty("--c",0);
  },5000);
  // */
});

.slider {
    -webkit-appearance: none;
    width: 100%;
    height: 10px;
    border-radius: 5px;   
    background: #ccc;
    outline: none;
}

.slider::-webkit-slider-thumb {
    -webkit-appearance: none;
    appearance: none;
    width: 20px;
    height: 20px;
    border-radius: 50%; 
    background: #6c757d;
    cursor: pointer;
    z-index: 5;
    box-shadow:var(--c,0) 0 0 red;
}

.slider::-moz-range-thumb {
    width: 20px;
    height: 20px;
    border-radius: 50%;
    background: #6c757d;
    cursor: pointer;
    z-index: 5;
    box-shadow:var(--c,0) 0 0 red;
}
.slider_wrapper {
    width: 150px;
}

<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>

<div id="slider_1_wrapper" class="slider_wrapper">
  <input type="range" id="slider_1" class="slider" min="0" max="1.0" step="any">
</div>