javascript - Can I gray out a <label> when the item associated with it is disabled? - Stack Overflow

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I want to disable a label when the input element associated with it is disabled. Here is my code:

                <!-- TODO: Gray this label out initially. -->
                <label id="spacesPerIndentLabel">Spaces per indent: 4</label>
                <br>
                <input id="spacesPerIndent" type="text" disabled>

I can't figure out how to make the label disabled. I tried putting disabled on the label, but had no luck because label isn't an element that supports disabled. I also thought of selecting

label + input:disabled { ... }

but that would select the disabled input instead of the label. After some further research I found out that CSS has no "previous sibling" selector (like + is the "next sibling" selector).

I want to disable a label when the input element associated with it is disabled. Here is my code:

                <!-- TODO: Gray this label out initially. -->
                <label id="spacesPerIndentLabel">Spaces per indent: 4</label>
                <br>
                <input id="spacesPerIndent" type="text" disabled>

I can't figure out how to make the label disabled. I tried putting disabled on the label, but had no luck because label isn't an element that supports disabled. I also thought of selecting

label + input:disabled { ... }

but that would select the disabled input instead of the label. After some further research I found out that CSS has no "previous sibling" selector (like + is the "next sibling" selector).

• javascript
• html
• css

Share Improve this question Follow edited Jan 22, 2018 at 6:43 VXp 12.1k66 gold badges3333 silver badges4747 bronze badges asked Jan 21, 2018 at 22:55 James KoJames Ko 34.6k3434 gold badges145145 silver badges253253 bronze badges 3

• 1 You can still add disabled to your <label>, you'd just have to style it with CSS, eg label[disabled] { opacity: 0.4; } – Phil Commented Jan 21, 2018 at 22:57
• @Phil Oh, I tried using label:disabled instead of [disabled]. I'll try your suggestion, thanks. Why do you think :disabled didn't work? – James Ko Commented Jan 21, 2018 at 23:01
• Because the :disabled pseudo-class only works on elements that support the disabled property. [disabled] is using an attribute selector – Phil Commented Jan 21, 2018 at 23:03

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5 Answers 5

Sorted by: Reset to default 3

You could use css flexbox to position your elements.

https://jsfiddle/c1d81r8b/4/

HTML:

<div class="container">
  <input id="test1" type="text">
  <label for="test1">Test 1 label</label>
</div>
<br>
<br>
<div class="container">
  <input id="test2" type="text" disabled>
  <label for="test2">Test 2 label</label>
</div>

CSS:

.container {
  display: flex;
  flex-direction: column;
}

.container label {
  order: 1;
}

.container input {
  order: 2;
}

.container input[disabled] + label {
  background: grey;
}

This lets your use CSS to set the order the elements are displayed in, and allows you to use the sibling selector.

See https://caniuse./#feat=flexbox for browser support notes.

If you're happy to add extra attributes or classes to your <label> elements, you can use CSS to style them appropriately. For example

<label disabled id="spacesPerIndentLabel">Spaces per indent: 4</label>
<!-- or -->
<label class="disabled" id="spacesPerIndentLabel">Spaces per indent: 4</label>

your CSS could look like

label.disabled, label[disabled] {
  opacity: .4;
}

First of all the markup of your label is not patible with the standard i.e it has not the for attribute. See this or at least it should wrap its element.

So first, your HTML should be something like the following:

<label id="spacesPerIndentLabel" for="spacesPerIndent">Spaces per indent: 4</label>
<br>
<input id="spacesPerIndent" type="text" disabled>

Then using javascript we will add class to each label that its for element is disabled like the following:

labels = document.getElementsByTagName('label');
    for (i = 0; i < labels.length; i++){
      forId = labels[i].attributes.for.value
      if (document.getElementById(forId).attributes.disabled){
        labels[i].className = 'dis'
      }
    }

Checkout this DEMO

If you're happy with putting a wrapper around your input and label that uses position relative, and positioning your label absolutely, you can try this method:

CSS:

.container {
  position: relative;
  padding-top: 1.1em;
}

.container label {
  position: absolute;
  left: 0;
  top: 0;
}

.container input[disabled] + label {
  background: grey;
}

HTML:

<div class="container">
  <input id="test1" type="text">
  <label for="test1">Test 1 label</label>
</div>

<div class="container">
  <input id="test2" type="text" disabled>
  <label for="test2">Test 2 label</label>
</div>

JSFiddle: https://jsfiddle/c1d81r8b/3/

Essentially this just places the label after your inputs so they can be targeted with the sibling selector, but then positions them before it. The 1.1em padding top on the container is what makes space for the label to sit - adjust this to match your label font size and any required padding/margins there.

Note that this will not be appropriate if your label text needs to wrap at any point - so use with caution.

Nowadays you can do the following (if you have a future release date/only need to support new browsers):

<label>
  Hello
  <input type="text" disabled />
</label>

input:disabled {
  background: lightgray;
}

label:has(:disabled) {
  color: lightgray;
}

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