Element: checkVisibility() method

The checkVisibility() method of the Element interface checks whether the element is visible.

The method returns false in either of the following situations:

• The element doesn't have an associated box, for example because the CSS display property is set to none or contents.
• The element is not being rendered because the element or an ancestor element sets the content-visibility property to hidden.

The optional parameter enables additional checks to test for other interpretations of what "visible" means. For example, you can further check whether an element has an opacity of 0, if the value of the element visibility property makes it invisible, or if the element content-visibility property has a value of auto and its rendering is currently being skipped.

Syntax

checkVisibility(options)

Parameters

options Optional

An object indicating additional checks to run. The possible options are:

contentVisibilityAuto

true to check if the element content-visibility property has (or inherits) the value auto, and it is currently skipping its rendering. false by default.

opacityProperty

true to check if the element opacity property has (or inherits) a value of 0. false by default.

visibilityProperty

true to check if the element is invisible due to the value of its visibility property. false by default.

Note: Invisible elements include those that have visibility: hidden, and some element types that have visibility: collapse.

checkOpacity

A historic alias for opacityProperty.

checkVisibilityCSS

A historic alias for visibilityProperty.

Return value

false if any of the following conditions are met, otherwise true:

• The element doesn't have an associated box.
• The element content-visibility property has (or inherits) a value of hidden.
• opacityProperty (or checkOpacity) is true and the element opacity property has (or inherits) a value of 0.
• visibilityProperty (or checkVisibilityCSS) is true and the element is invisible due to the value of its visibility property.
• contentVisibilityAuto is true, the content-visibility property has (or inherits) a value of auto, and element rendering is being skipped.

Examples

Test checkVisibility() with varied CSS

The following example allows you to test how the result of checkVisibility() might change with different values for display, content-visibility, visibility, and opacity CSS properties.

HTML

The HTML defines a <select> element for the CSS properties that affect the results of checkVisibility(). The first (default selected) values should result in checkVisibility() returning true when applied to an element, while the other values affect the visibility.

<select id="css_display" name="css_display">
  <option value="block" selected>display: block</option>
  <option value="none">display: none</option>
  <option value="content">display: content</option>
</select>

<select id="css_content_visibility" name="css_content_visibility">
  <option value="visible" selected>content-visibility: visible</option>
  <option value="hidden">content-visibility: hidden</option>
  <option value="auto">content-visibility: auto</option>
</select>

<select id="css_opacity" name="css_opacity">
  <option value="1" selected>opacity: 1</option>
  <option value="0">opacity: 0</option>
</select>

<select id="css_visibility" name="css_visibility">
  <option value="visible" selected>visibility: visible</option>
  <option value="hidden">visibility: hidden</option>
  <option value="collapse">visibility: collapse</option>
</select>

Next we have a <pre> that is used to output the result of the checkVisibility() check when no options are passed in the parameter, and for each separate option value. At the end we have the element that will be tested (to which we will apply the selected CSS property values).

<pre id="output_result"></pre>
<div id="test_element">The element to be checked for visibility.</div>

CSS

The CSS just highlights the element to be tested.

#test_element {
  border: solid;
  border-color: blue;
}

JavaScript

The code below gets each of the <select> elements. The updateCSS() method is called on start and whenever the select elements change in order to apply the selected CSS to the target element,

const displayCssSelect = document.getElementById("css_display");
const contentVisibilityCssSelect = document.getElementById(
  "css_content_visibility",
);
const displayCssOpacity = document.getElementById("css_opacity");
const displayCssVisibility = document.getElementById("css_visibility");

const outputResult = document.getElementById("output_result");
const elementToCheck = document.getElementById("test_element");

updateCSS();

const cssSelectors = document.querySelectorAll("select");
cssSelectors.forEach((select) => {
  select.addEventListener("change", (event) => {
    updateCSS();
  });
});

function updateCSS() {
  // Apply selected CSS properties to target element
  elementToCheck.style.display = displayCssSelect.value;
  elementToCheck.style.contentVisibility = contentVisibilityCssSelect.value;
  elementToCheck.style.opacity = displayCssOpacity.value;
  elementToCheck.style.visibility = displayCssVisibility.value;

  // Call checkVisibility() on element using default and each of options
  const defaultVisibilityCheck = elementToCheck.checkVisibility();
  const opacityVisibilityCheck = elementToCheck.checkVisibility({
    opacityProperty: true,
  });
  const cssVisibilityCheck = elementToCheck.checkVisibility({
    visibilityProperty: true,
  });
  const contentVisibilityAutoCheck = elementToCheck.checkVisibility({
    contentVisibilityAuto: true,
  });

  // Output the results of the tests
  outputResult.innerText = `Checks on element below (may be hidden):
- Result of checkVisibility(): ${defaultVisibilityCheck}
- Result of checkVisibility({opacityProperty: true}): ${opacityVisibilityCheck}
- Result of checkVisibility({visibilityProperty: true}): ${cssVisibilityCheck}
- Result of checkVisibility({contentVisibilityAuto: true}): ${contentVisibilityAutoCheck}`;
}

Result

The results are shown below. If you change the selection the results will be applied to the test element (blue outline) and the results of the checkVisibility() for each setting should be displayed. So for example, if you set the opacity: 0 that test (only) should indicate false. However if you set display: none then all tests should return false.

Specifications

Browser compatibility