HX-Trigger

Basic Usage

Send a single event:

HX-Trigger: myEvent

By default, the event is dispatched on the element that made the request and bubbles. Use from:body when listening elsewhere.

Listen from markup with hx-on:

<div hx-on="myEvent from:body -> this.classList.add('updated')"></div>

Send multiple events:

HX-Trigger: event1, event2

Event Detail

Send event detail with a JSON object:

HX-Trigger: {"notification":"Hello World"}

Scalar values are available on detail.value:

<div hx-on="notification from:body -> alert(value)"></div>

You can also listen from JavaScript:

document.body.addEventListener("notification", (evt) => {
    alert(evt.detail.value); // "Hello World"
});

Send multiple detail fields with a nested object:

HX-Trigger: {"notification":{"level":"info", "message":"Saved"}}

Each nested property is copied onto the event detail:

<div hx-on="notification from:body -> this.dataset.level = level; this.textContent = message"></div>

Send multiple events with detail by adding properties to the top-level JSON object:

HX-Trigger: {"notification":"Saved", "refreshList":true}

<div hx-on="notification from:body -> this.textContent = value;
            refreshList from:body -> this.dataset.refresh = value"></div>

Targeting Other Elements

Trigger an event on another element with target:

HX-Trigger: {"notification":{"target":"#notifications", "message":"Saved"}}

The target value is resolved as a selector. The event is dispatched on that element instead of the source element.

<div id="notifications" hx-on="notification -> this.textContent = message"></div>

This can update client-owned state while the response swaps normal HTML elsewhere:

HX-Trigger: {"cartUpdated":{"target":"#cart", "count":3}}

<div id="cart" data-count="0" hx-on="cartUpdated -> data.count = count">
    Cart (<span :text="data.count"></span>)
</div>

This example uses the hx-live extension.

Notes

Response headers are not processed on 3xx response codes. Return a 2xx status when using this header.

In htmx 2, there were three variants: HX-Trigger, HX-Trigger-After-Swap, and HX-Trigger-After-Settle. In htmx 4, these were consolidated into a single HX-Trigger header that fires after the swap completes.

See Also

• htmx.trigger()