# Loading Indicators
Loading indicators express an unspecified wait time of a process.
**Contents**
* [Using loading indicators](#using-progress-indicators)
* [Linear progress indicators](#linear-progress-indicators)
* [Circular progress indicators](#circular-progress-indicators)
* [Anatomy and key properties](#anatomy-and-key-properties)
* [Theming progress indicators](#theming-progress-indicators)
## Using loading indicators
Before you can use Material loading indicators, you need to add a dependency to
the Material Components for Android library. For more information, go to the
[Getting started](https://github.com/material-components/material-components-android/tree/master/docs/getting-started.md)
page.
Loading indicators inform users about the indeterminate ongoing processes, such
as loading an app, submitting a form, or saving updates. They communicate an
app’s state and indicate available actions, such as whether users can navigate
away from the current screen. It's recommended as a replacement for
indeterminate circular progress indicators.
**Note:** Use progress indicators, if the processes can transition from
indeterminate to determinate.
### Usage
A loading indicator can be added to a layout:
```xml
```
```xml
```
### Making loading indicators accessible
Loading indicators have support very limited user interactions. Please consider
setting the content descriptor for use with screen readers.
That can be done in XML via the `android:contentDescription` attribute or
programmatically like so:
```kt
loadingIndicator.contentDescription = contentDescription
```
For contained loading indicators, please ensure the indicator color and the
container color have enough contrast (3:1).
## Loading indicators
Loading indicators capture attention through motion. It morphs the shape in a
sequence with potential color change, if multiple colors are specified for the
indicator. A fully rounded container is optionally drawn behind the morphing
shape.
Source code:
* `LoadingIndicator`
* [Class source](https://github.com/material-components/material-components-android/tree/master/lib/java/com/google/android/material/loadingindicator/LoadingIndicator.java)
### Anatomy and key properties
A loading indicator consists of an optional container and an indicator.
1. Active indicator
2. Container
#### Attributes
Element | Attribute | Related method(s) | Default value
-------------------- | --------------------- | --------------------------------------------- | -------------
**Indicator color** | `app:indicatorColor` | `setIndicatorColor``getIndicatorColor` | `colorPrimary`
**Container color** | `app:containerColor` | `setContainerColor``getContainerColor` | `transparent`
**Indicator size** | `app:indicatorSize` | `setIndicatorSize``getIndicatorSize` | 38dp
**Container width** | `app:containerWidth` | `setContainerWidth``getContainerWidth` | 48dp
**Container height** | `app:containerHeight` | `setContainerHeight``getContainerHeight` | 48dp
#### Styles
Element | Style
------------------- | ---------------------------------------------
**Default style** | `Widget.Material3.LoadingIndicator`
**Contained style** | `Widget.Material3.LoadingIndicator.Contained`
Default theme attribute: `?attr/loadingIndicatorStyle`
See the full list of
[styles](https://github.com/material-components/material-components-android/tree/master/lib/java/com/google/android/material/loadingindicator/res/values/styles.xml)
and
[attributes](https://github.com/material-components/material-components-android/tree/master/lib/java/com/google/android/material/loadingindicator/res/values/attrs.xml).