transitions.md

Using CSS classes, it is possible to implement transitions for when the modal is opened or closed.

Basic overlay styling

By placing the following CSS somewhere in your project's styles, you can make the modal content fade in when it is opened and fade out when it is closed:

.ReactModal__Overlay {
    opacity: 0;
    transition: opacity 2000ms ease-in-out;
}

.ReactModal__Overlay--after-open{
    opacity: 1;
}

.ReactModal__Overlay--before-close{
    opacity: 0;
}

The above example will apply the fade transition globally, affecting all modals whose afterOpen and beforeClose classes have not been set via the className prop. To apply the transition to one modal only, you can change the above class names and pass an object to your modal's className prop as described in the previous section.

Gracefully closing the modal

In order for the fade transition to work, you need to inform the <Modal /> about the transition time required for the animation.

Like this

<Modal closeTimeoutMS={2000} />

closeTimeoutMS is expressed in milliseconds.

The closeTimeoutMS value and the value used in CSS or style prop passed to <Modal /> needs to be the same.

Warning: if you are using React 16, the close transition works only if you use the isOpen prop to toggle the visibility of the modal.

Do not conditionally render the <Modal />.

Instead of this

{
  this.state.showModal &&
  <Modal
    closeTimeoutMS={200}
    isOpen
    contentLabel="modal"
    onRequestClose={() => this.toggleModal()}
  >
    <h2>Add modal content here</h2>
  </Modal>
}

Do this

{
  <Modal
    closeTimeoutMS={200}
    isOpen={this.state.showModal}
    contentLabel="modal"
    onRequestClose={() => this.toggleModal()}
  >
    <h2>Add modal content here</h2>
  </Modal>
}

Styling the overlay and content

It is possible to independently style the transitions for the modal overlay and modal content.

Keep in mind that inline styles will take precedence over those defined as CSS rules. In case you need to use both at the same time, you'll need to use the css !important.

The example below will fade the overlay in and slide the modal content on-screen from the bottom of the page:

{
  <Modal
    style={{
      overlay: { background: 'rgba(0, 0, 0, 0.3)' },
      content: {
        top: '50%',
        left: '50%',
        right: 'auto',
        bottom: 'auto',
        marginRight: '-50%',
        // transform: 'translate(-50%, -50%)', if you use inline styles instead of css 
      },
    }}
    closeTimeoutMS={800}
    isOpen={this.state.showModal}
    contentLabel="modal"
    onRequestClose={() => this.toggleModal()}
  >
    <h2>Add modal content here</h2>
  </Modal>
}

Corresponding CSS:

.ReactModal__Overlay {
  opacity: 0;
  transition: opacity 800ms ease-in-out;
}

.ReactModal__Overlay--after-open{
  opacity: 1;
}

.ReactModal__Overlay--before-close{
  opacity: 0;
}

.ReactModal__Content {
  transform: translate(-50%, 150%);
  transition: transform 800ms ease-in-out;
}

.ReactModal__Content--after-open {
  transform: translate(-50%, -50%);
}

.ReactModal__Content--before-close {
  transform: translate(-50%, 150%);
}

Notes

React Modal has adopted the stable Portal API as exposed in React 16.

And createProtal API from React 16 no longer allow developers to intervene the unmounting of the portal component.