import Props from '@ionic-internal/component-api/v8/refresher/props.md'; import Events from '@ionic-internal/component-api/v8/refresher/events.md'; import Methods from '@ionic-internal/component-api/v8/refresher/methods.md'; import Parts from '@ionic-internal/component-api/v8/refresher/parts.md'; import CustomProps from '@ionic-internal/component-api/v8/refresher/custom-props.mdx'; import Slots from '@ionic-internal/component-api/v8/refresher/slots.md';

import EncapsulationPill from '@components/page/api/EncapsulationPill';

Refresher provides pull-to-refresh functionality on a content component. The pull-to-refresh pattern lets a user pull down on a list of data in order to retrieve more data.

Data should be modified during the refresher's output events. Once the async operation has completed and the refreshing should end, complete() needs to be called on the refresher.

import Basic from '@site/static/usage/v8/refresher/basic/index.md';

The refresher has several properties for customizing the pull gesture. Set the pullFactor to change the speed of the pull, the pullMin property to change the minimum distance the user must pull down, and the pullMax property to change the maximum distance the user must pull down before the refresher enters the refreshing state.

These properties do not apply when the native refresher is enabled.

import PullProperties from '@site/static/usage/v8/refresher/pull-properties/index.md';

The default icon, spinner, and text can be customized on the refresher content based on whether the state of the refresher is pulling or refreshing.

Setting pullingIcon will disable the native refresher.

import CustomContent from '@site/static/usage/v8/refresher/custom-content/index.md';

Both iOS and Android platforms provide refreshers that use properties exposed by their respective devices in order to give pull-to-refresh a fluid, native-like feel.

The iOS and Material Design native refreshers are enabled by default in Ionic. However, the native iOS refresher relies on rubber band scrolling in order to work properly and is only compatible with iOS devices as a result. We provide a fallback refresher for apps running in iOS mode on devices that do not support rubber band scrolling.

The native refresher uses a circular spinner for Material Design, while iOS uses the lines spinner. On iOS, the tick marks will progressively show as the page is pulled down.

Certain refresher properties such as the Pull Properties, closeDuration and snapbackDuration are not compatible because much of the native refreshers are scroll-based. See Properties for more information on unsupported properties.

The native refreshers can be disabled by setting the pullingIcon on the refresher content to any icon or spinner. See the Ionicons and Spinner documentation for accepted values.

Refresher requires a scroll container to function. When using a virtual scrolling solution, you will need to disable scrolling on the ion-content and indicate which element container is responsible for the scroll container with the .ion-content-scroll-host class target.

Developers should apply the following CSS to the scrollable container. This CSS adds a "rubber band" scrolling effect on iOS which allows the native iOS refresher to work properly:

.ion-content-scroll-host::before,
.ion-content-scroll-host::after {
  position: absolute;
  
  width: 1px;
  height: 1px;
  
  content: "";
}

.ion-content-scroll-host::before {
  bottom: -1px;
}

.ion-content-scroll-host::after {
  top: -1px;
}

import CustomScrollTarget from '@site/static/usage/v8/refresher/custom-scroll-target/index.md';

While the refresher can be used with any type of content, a common use case in native apps is to display a list of data that gets updated on refresh. In the below example, the app generates a list of data and then appends data to the top of the list when the refresh is completed. In a real app, the data would be received and updated after sending a request via a network or database call.

import Advanced from '@site/static/usage/v8/refresher/advanced/index.md';

interface RefresherEventDetail {
  complete(): void;
}

While not required, this interface can be used in place of the CustomEvent interface for stronger typing with Ionic events emitted from this component.

interface RefresherCustomEvent extends CustomEvent {
  detail: RefresherEventDetail;
  target: HTMLIonRefresherElement;
}