RefreshIndicator class

A widget that supports the Material "swipe to refresh" idiom.

When the child's Scrollable descendant overscrolls, an animated circular progress indicator is faded into view. When the scroll ends, if the indicator has been dragged far enough for it to become completely opaque, the onRefresh callback is called. The callback is expected to update the scrollable's contents and then complete the Future it returns. The refresh indicator disappears after the callback's Future has completed.

The trigger mode is configured by RefreshIndicator.triggerMode.

Troubleshooting

Refresh indicator does not show up

The RefreshIndicator will appear if its scrollable descendant can be overscrolled, i.e. if the scrollable's content is bigger than its viewport. To ensure that the RefreshIndicator will always appear, even if the scrollable's content fits within its viewport, set the scrollable's Scrollable.physics property to AlwaysScrollableScrollPhysics:

ListView(
  physics: const AlwaysScrollableScrollPhysics(),
  // ...
)

A RefreshIndicator can only be used with a vertical scroll view.

See also:

• material.io/design/platform-guidance/android-swipe-to-refresh.html
• RefreshIndicatorState, can be used to programmatically show the refresh indicator.
• RefreshProgressIndicator, widget used by RefreshIndicator to show the inner circular progress spinner during refreshes.
• CupertinoSliverRefreshControl, an iOS equivalent of the pull-to-refresh pattern. Must be used as a sliver inside a CustomScrollView instead of wrapping around a ScrollView because it's a part of the scrollable instead of being overlaid on top of it.