<dialog>: The Dialog element
The <dialog>
HTML element represents a modal or non-modal dialog box or other interactive component, such as a dismissible alert, inspector, or subwindow.
The HTML <dialog>
element is used to create both modal and non-modal dialog boxes. Modal dialog boxes interrupt interaction with the rest of the page being inert, while non-modal dialog boxes allow interaction with the rest of the page.
JavaScript should be used to display the <dialog>
element. Use the .showModal()
method to display a modal dialog and the .show()
method to display a non-modal dialog. The dialog box can be closed using the .close()
method or using the dialog
method when submitting a <form>
that is nested within the <dialog>
element. Modal dialogs can also be closed by pressing the Esc key.
Attributes
This element includes the global attributes.
Warning: The tabindex
attribute must not be used on the <dialog>
element.
open
-
Indicates that the dialog box is active and is available for interaction. If the open
attribute is not set, the dialog box will not be visible to the user. It is recommended to use the .show()
or .showModal()
method to render dialogs, rather than the open
attribute. If a <dialog>
is opened using the open
attribute, it is non-modal.
Note: While you can toggle between the open and closed states of non-modal dialog boxes by toggling the presence of the open
attribute, this approach is not recommended.
Usage notes
- HTML
<form>
elements can be used to close a dialog box if they have the attribute method="dialog"
or if the button used to submit the form has formmethod="dialog"
set. When a <form>
within a <dialog>
is submitted via the dialog
method, the dialog box closes, the states of the form controls are saved but not submitted, and the returnValue
property gets set to the value of the button that was activated. - The CSS
::backdrop
pseudo-element can be used to style the backdrop of a modal dialog, which is displayed behind the <dialog>
element when the dialog is displayed using the HTMLDialogElement.showModal()
method. For example, you can use this pseudo-element to obfuscate the inert content behind the modal dialog. - The
autofocus
attribute should be added to the element with which the user is expected to interact immediately on opening a modal dialog. If there is no element involving immediate interaction, the autofocus
attribute can be added to the <dialog>
element itself.
Examples
Caveats of creating a dialog using only HTML
This example demonstrates the create a non-modal dialog by using only HTML. Because of the boolean open
attribute in the <dialog>
element, the dialog appears open when the page loads. The dialog can be closed by clicking the "OK" button because the method
attribute in the <form>
element is set to "dialog"
. In this case, no JavaScript is needed to close the form.
<dialog open>
<p>Greetings, one and all!</p>
<form method="dialog">
<button>OK</button>
</form>
</dialog>
Result
This dialog is initially open because of the presence of the open
attribute. Dialogs that are displayed using the open
attribute are non-modal. You may notice that after clicking "OK", the dialog gets dismissed leaving the Result frame empty. When the dialog is dismissed, there is no method provided to reopen it. For this reason, the preferred method to display non-modal dialogs is by using the HTMLDialogElement.show()
method. It is possible to toggle the display of the dialog by adding or removing the boolean open
attribute, but it is not the recommended practice.
Creating a modal dialog
This example demonstrates a modal dialog with a gradient backdrop. The .showModal()
method opens the modal dialog when the "Show the dialog" button is activated. The dialog can be closed by pressing the Esc key or via the close()
method when the "Close" button within the dialog is activated.
When a dialog opens, the browser, by default, gives focus to the first element that can be focused within the dialog. In this example, the autofocus
attribute is applied to the "Close" button, giving it focus when the dialog opens, as this is the element we expect the user will interact with immediately after the dialog opens.
HTML
<dialog>
<button autofocus>Close</button>
<p>This modal dialog has a groovy backdrop!</p>
</dialog>
<button>Show the dialog</button>
CSS
We can style the backdrop of the dialog by using the ::backdrop
pseudo-element.
::backdrop {
background-image: linear-gradient(
45deg,
magenta,
rebeccapurple,
dodgerblue,
green
);
opacity: 0.75;
}
JavaScript
The dialog is opened modally using the .showModal()
method and closed using the .close()
method.
const dialog = document.querySelector("dialog");
const showButton = document.querySelector("dialog + button");
const closeButton = document.querySelector("dialog button");
showButton.addEventListener("click", () => {
dialog.showModal();
});
closeButton.addEventListener("click", () => {
dialog.close();
});
Result
When the modal dialog is displayed, it appears above any other dialogs that might be present. Everything outside the modal dialog is inert and interactions outside the dialog are blocked. Notice that when the dialog is open, with the exception of the dialog itself, interaction with the document is not possible; the "Show the dialog" button is mostly obfuscated by the almost opaque backdrop of the dialog and is inert.
Handling the return value from the dialog
This example demonstrates the returnValue
of the <dialog>
element and how to close a modal dialog by using a form. By default, the returnValue
is the empty string or the value of the button that submits the form within the <dialog>
element, if there is one.
This example opens a modal dialog when the "Show the dialog" button is activated. The dialog contains a form with a <select>
and two <button>
elements, which default to type="submit"
. An eventlistener updates the value of the "Confirm" button when the select option changes. If the "Confirm" button is activated to close the dialog, the current value of the button is the return value. If the dialog is closed by pressing the "Cancel" button, the returnValue
is cancel
.
When the dialog is closed, the return value is displayed under the "Show the dialog" button. If the dialog is closed by pressing the Esc key, the returnValue
is not updated and the close
event doesn't occur so the text in the <output>
is not updated.
HTML
<dialog id="favDialog">
<form>
<p>
<label>
Favorite animal:
<select>
<option value="default">Choose…</option>
<option>Brine shrimp</option>
<option>Red panda</option>
<option>Spider monkey</option>
</select>
</label>
</p>
<div>
<button value="cancel" formmethod="dialog">Cancel</button>
<button id="confirmBtn" value="default">Confirm</button>
</div>
</form>
</dialog>
<p>
<button id="showDialog">Show the dialog</button>
</p>
<output></output>
JavaScript
const showButton = document.getElementById("showDialog");
const favDialog = document.getElementById("favDialog");
const outputBox = document.querySelector("output");
const selectEl = favDialog.querySelector("select");
const confirmBtn = favDialog.querySelector("#confirmBtn");
showButton.addEventListener("click", () => {
favDialog.showModal();
});
selectEl.addEventListener("change", (e) => {
confirmBtn.value = selectEl.value;
});
favDialog.addEventListener("close", (e) => {
outputBox.value =
favDialog.returnValue === "default"
? "No return value."
: `ReturnValue: ${favDialog.returnValue}.`;
});
confirmBtn.addEventListener("click", (event) => {
event.preventDefault();
favDialog.close(selectEl.value);
});
Result
This example demonstrates the following three methods of closing modal dialogs:
The "Cancel" button includes the formmethod="dialog"
attribute, which overrides the <form>
's default GET
method. When a form's method is dialog
, the state of the form is saved but not submitted, and the dialog gets closed.
Without an action
, submitting the form via the default GET
method causes a page to reload. We use JavaScript to prevent the submission and close the dialog with the event.preventDefault()
and HTMLDialogElement.close()
methods, respectively.
It is important to provide a closing mechanism within every dialog
element. The Esc key does not close non-modal dialogs by default, nor can one assume that a user will even have access to a physical keyboard (e.g., someone using a touch screen device without access to a keyboard).
Technical summary
Accessibility considerations
When implementing a dialog, it is important to consider the most appropriate place to set user focus. When using HTMLDialogElement.showModal()
to open a <dialog>
, focus is set on the first nested focusable element. Explicitly indicating the initial focus placement by using the autofocus
attribute will help ensure initial focus is set on the element deemed the best initial focus placement for any particular dialog. When in doubt, as it may not always be known where initial focus could be set within a dialog, particularly for instances where a dialog's content is dynamically rendered when invoked, the <dialog>
element itself may provide the best initial focus placement.
Ensure a mechanism is provided to allow users to close the dialog. The most robust way to ensure that all users can close the dialog is to include an explicit button to do so, such as a confirmation, cancellation, or close button.
By default, a dialog invoked by the showModal()
method can be dismissed by pressing the Esc key. A non-modal dialog does not dismiss via the Esc key by default, and depending on what the non-modal dialog represents, it may not be desired for this behavior. Keyboard users expect the Esc key to close modal dialogs; ensure that this behavior is implemented and maintained. If multiple modal dialogs are open, pressing the Esc key should close only the last shown dialog. When using <dialog>
, this behavior is provided by the browser.
While dialogs can be created using other elements, the native <dialog>
element provides usability and accessibility features that must be replicated if you use other elements for a similar purpose. If you're creating a custom dialog implementation, ensure that all expected default behaviors are supported and proper labeling recommendations are followed.
The <dialog>
element is exposed by browsers in a manner similar to custom dialogs that use the ARIA role="dialog" attribute. <dialog>
elements invoked by the showModal()
method implicitly have aria-modal="true", whereas <dialog>
elements invoked by the show()
method or displayed using the open
attribute or by changing the default display
of a <dialog>
are exposed as [aria-modal="false"]
. When implementing modal dialogs, everything other than the <dialog>
and its contents should be rendered inert using the inert
attribute. When using <dialog>
along with the HTMLDialogElement.showModal()
method, this behavior is provided by the browser.
Specifications
Browser compatibility
|
Desktop |
Mobile |
|
Chrome |
Edge |
Firefox |
Internet Explorer |
Opera |
Safari |
WebView Android |
Chrome Android |
Firefox for Android |
Opera Android |
Safari on IOS |
Samsung Internet |
dialog |
37 |
79 |
98 |
No |
24 |
15.4 |
37 |
37 |
98 |
24 |
15.4 |
3.0 |
open |
37 |
79 |
98 |
No |
24 |
15.4 |
37 |
37 |
98 |
24 |
15.4 |
3.0 |
See also