CircularProgressIndicator class

A Material Design circular progress indicator, which spins to indicate that the application is busy.

A widget that shows progress along a circle. There are two kinds of circular progress indicators:

• Determinate. Determinate progress indicators have a specific value at each point in time, and the value should increase monotonically from 0.0 to 1.0, at which time the indicator is complete. To create a determinate progress indicator, use a non-null value between 0.0 and 1.0.
• Indeterminate. Indeterminate progress indicators do not have a specific value at each point in time and instead indicate that progress is being made without indicating how much progress remains. To create an indeterminate progress indicator, use a null value.

The indicator arc is displayed with valueColor, an animated value. To specify a constant color use: AlwaysStoppedAnimation<Color>(color).

This example showcases determinate and indeterminate CircularProgressIndicators. The CircularProgressIndicators will use the when setting the CircularProgressIndicator.year2023 flag to false.

link

To create a local project with this code sample, run:
flutter create --sample=material.CircularProgressIndicator.1 mysample

See also:

• LinearProgressIndicator, which displays progress along a line.
• RefreshIndicator, which automatically displays a CircularProgressIndicator when the underlying vertical scrollable is overscrolled.
• material.io/design/components/progress-indicators.html#circular-progress-indicators