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title
trigger

Trigger an event on a DOM element.

Syntax

.trigger(eventName)
.trigger(eventName, position)
.trigger(eventName, options)
.trigger(eventName, x, y)
.trigger(eventName, position, options)
.trigger(eventName, x, y, options)

Usage

{% fa fa-check-circle green %} Correct Usage

cy.get('a').trigger('mousedown') // Trigger mousedown event on link

{% fa fa-exclamation-triangle red %} Incorrect Usage

cy.trigger('touchstart')             // Errors, cannot be chained off 'cy'
cy.location().trigger('mouseleave')  // Errors, 'location' does not yield DOM element

Arguments

{% fa fa-angle-right %} eventName (String)

The name of the event to be triggered on the DOM element.

{% fa fa-angle-right %} position (String)

The position where the event should be triggered. The center position is the default position. Valid positions are topLeft, top, topRight, left, center, right, bottomLeft, bottom, and bottomRight.

{% imgTag /img/api/coordinates-diagram.jpg "cypress-command-positions-diagram" %}

{% fa fa-angle-right %} x (Number)

The distance in pixels from element's left to trigger the event.

{% fa fa-angle-right %} y (Number)

The distance in pixels from element's top to trigger the event.

{% fa fa-angle-right %} options (Object)

Pass in an options object to change the default behavior of .trigger().

Option Default Description
log true {% usage_options log %}
force false {% usage_options force trigger %}
bubbles true Whether the event bubbles
cancelable true Whether the event is cancelable
timeout {% url defaultCommandTimeout configuration#Timeouts %} {% usage_options timeout .trigger %}

You can also include arbitrary event properties (e.g. clientX, shiftKey) and they will be attached to the event. Passing in coordinate arguments (clientX, pageX, etc) will override the position coordinates.

Yields {% helper_icon yields %}

{% yields same_subject .trigger %}

Examples

Mouse Events

Trigger a mouseover on the button

The DOM element must be in an "interactable" state prior to the triggered event happening (it must be visible and not disabled).

cy.get('button').trigger('mouseover') // yields 'button'

Simulate a "long press" event

cy.get('.target').trigger('mousedown')
cy.wait(1000)
cy.get('.target').trigger('mouseleave')

jQuery UI Sortable

To simulate drag and drop using jQuery UI sortable requires pageX and pageY properties along with which:1.

cy.get('[data-cy=draggable]')
  .trigger('mousedown', { which: 1, pageX: 600, pageY: 100 })
  .trigger('mousemove', { which: 1, pageX: 600, pageY: 600 })
  .trigger('mouseup')

Drag and Drop

{% note info %} {% url 'Check out our example recipe triggering mouse and drag events to test dragging and dropping' recipes#Drag-and-Drop %} {% endnote %}

Change Event

Interact with a range input (slider)

To interact with a range input (slider), we need to set its value and then trigger the appropriate event to signal it has changed.

Below we invoke jQuery's val() method to set the value, then trigger the change event.

Note that some implementations may rely on the input event instead, which is fired as a user moves the slider, but is not supported by some browsers.

cy.get('input[type=range]').as('range')
  .invoke('val', 25)
  .trigger('change')

cy.get('@range').siblings('p').should('have.text', '25')

Position

Trigger a mousedown on the top right of a button

cy.get('button').trigger('mousedown', 'topRight')

Coordinates

Specify explicit coordinates relative to the top left corner

cy.get('button').trigger('contextmenu', 15, 40)

Options

Specify that the event should not bubble

By default, the event will bubble up the DOM tree. This will prevent the event from bubbling.

cy.get('button').trigger('mouseover', { bubbles: false })

Specify the exact clientX and clientY the event should have

This overrides the default auto-positioning based on the element itself. Useful for events like mousemove where you need the position to be outside the element itself.

cy.get('button').trigger('mousemove', { clientX: 200, clientY: 300 })

Notes

Actionability

The element must first reach actionability

.trigger() is an "action command" that follows all the rules {% url 'defined here' interacting-with-elements %}.

Events

What event should I fire?

cy.trigger() is meant to be a low-level utility that makes triggering events easier than manually constructing and dispatching them. Since any arbitrary event can be triggered, Cypress tries not to make any assumptions about how it should be triggered. This means you'll need to know the implementation details (which may be in a 3rd party library) of the event handler(s) receiving the event and provide the necessary properties.

Differences

What's the difference between triggering and event and calling the corresponding cypress command?

In other words, what's the difference between:

cy.get('button').trigger('focus')
cy.get('button').focus()

// ... or ...

cy.get('button').trigger('click')
cy.get('button').click()

Both types commands will first verify element actionability, but only the "true" action commands will implement all of the default actions of the browser, and additionally perform low level actions to fulfill what's defined in the spec.

.trigger() will only fire the corresponding event and do nothing else.

That means that your event listener callbacks will be invoked, but don't expect the browser to actually "do" anything for these events. For the most part, it shouldn't matter, which is why .trigger() is an excellent stop-gap if the command / event you're looking for hasn't been implemented yet.

Rules

Requirements {% helper_icon requirements %}

{% requirements dom .trigger %}

Assertions {% helper_icon assertions %}

{% assertions actions .trigger %}

Timeouts {% helper_icon timeout %}

{% timeouts actions .trigger %}

Command Log

Trigger a change event on input type='range'

cy.get('.trigger-input-range')
  .invoke('val', 25)
  .trigger('change')

The commands above will display in the Command Log as:

{% imgTag /img/api/trigger/command-log-trigger.png "command log trigger" %}

When clicking on trigger within the command log, the console outputs the following:

{% imgTag /img/api/trigger/console-log-trigger.png "console log trigger" %}

{% history %} {% url "0.20.0" changelog#0-20-0 %} | .trigger() command added {% endhistory %}

See also

  • {% url .blur() blur %}
  • {% url .check() check %}
  • {% url .click() click %}
  • {% url .focus() focus %}
  • {% url .select() select %}
  • {% url .submit() submit %}
  • {% url .type() type %}
  • {% url .uncheck() uncheck %}