2021-10-05 08:57:06 -04:00

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<!--docs:
title: "Navigation Rail"
layout: detail
section: components
excerpt: "Navigation rails provide access to primary destinations in your app on tablet and desktop screens.
iconId: navigation_rail
path: /catalog/navigation-rail/
-->
# Navigation Rail
[Navigation rail](https://material.io/components/navigation-rail/#) provides
access to primary destinations in your app on tablet and desktop screens.
![The navigation rail container is 80 dp wide by default.](assets/navigationrail/navigation-rail-default.png)
**Contents**
* [Using navigation rail](#using-navigation-rail)
* [Navigation rail example](#navigation-rail-example)
* [Theming](#theming-a-navigation-rail)
## Using navigation rail
Before you can use the Material Navigation Rail, 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.
A typical layout will look similar to this:
```xml
<com.google.android.material.navigationrail.NavigationRailView
android:id="@+id/navigation_rail"
android:layout_width="wrap_content"
android:layout_height="match_parent"
app:menu="@menu/navigation_rail_menu" />
```
**Note:** The width of a `NavigationRailView` will be 80dp wide by default.The
width of the rail can be changed by setting the `android:layout_width`attribute
to a specific DP value.
In `navigation_rail_menu.xml` inside a `menu` resource directory:
```xml
<menu xmlns:android="http://schemas.android.com/apk/res/android">
<item
android:id="@+id/alarms"
android:enabled="true"
android:icon="@drawable/icon_alarms"
android:title="@string/alarms_destination_label"/>
<item
android:id="@+id/schedule"
android:enabled="true"
android:icon="@drawable/icon_clock"
android:title="@string/schedule_destination_label"/>
<item
android:id="@+id/timer"
android:enabled="true"
android:icon="@drawable/icon_sand_clock"
android:title="@string/timer_destination_label"/>
<item
android:id="@+id/stopwatch"
android:enabled="true"
android:icon="@drawable/icon_stop_watch"
android:title="@string/stopwatch_destination_label"/>
</menu>
```
**Note:** `NavigationRailView` displays three to no more than seven app
destinations, and can include a header view. Each destination is represented by
an icon and a text label.
In code:
```kt
// Listeners are defined on the super class NavigationBarView
// to support both NavigationRail and BottomNavigation with the
// same listeners
NavigationBarView.OnNavigationItemSelectedListener { item ->
when(item.itemId) {
R.id.alarms -> {
// Respond to alarm navigation item click
true
}
R.id.schedule -> {
// Respond to schedule navigation item click
true
}
else -> false
}
}
```
There's also a method for detecting if navigation items have been reselected:
```kt
navigationRail.setOnNavigationItemReselectedListener { item ->
when(item.itemId) {
R.id.item1 -> {
// Respond to navigation item 1 reselection
}
R.id.item2 -> {
// Respond to navigation item 2 reselection
}
}
}
```
Which results in:
![The navigation rail container is 72 dp wide by default.](assets/navigationrail/navigation-rail-demo.png)
### Making navigation rail accessible
You should set an `android:title` for each of your `menu` items so that screen
readers like TalkBack can properly announce what each navigation item
represents:
```xml
<menu xmlns:android="http://schemas.android.com/apk/res/android">
<item
...
android:title="@string/text_label"/>
...
</menu>
```
The `labelVisibilityMode` attribute can be used to adjust the behavior of the
text labels for each navigation item. There are four visibility modes:
* `LABEL_VISIBILITY_AUTO` (default): The label behaves as “labeled” when there
are 3 items or less, or “selected” when there are 4 items or more
* `LABEL_VISIBILITY_SELECTED`: The label is only shown on the selected
navigation item
* `LABEL_VISIBILITY_LABELED`: The label is shown on all navigation items
* `LABEL_VISIBILITY_UNLABELED`: The label is hidden for all navigation items
### Adding a header view
The rail provides a convenient container for anchoring a header view, such as a
`FloatingActionButton` or a logo, to the top of the rail, using the
`app:headerLayout` attribute.
![Navigation rail with badges](assets/navigationrail/navigation-rail-fab.png)
```xml
<com.google.android.material.navigationrail.NavigationRailView
android:id="@+id/navigation_rail"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
app:headerLayout="@layout/navigation_rail_fab"
app:menu="@menu/navigation_rail_menu" />
```
The header view can also be added or removed at runtime using the following
methods:
**Method** | **Description**
---------------------------------------- | ---------------
`void addHeaderView(@NonNull View view)` | The specified header view will be attached to the NavigationRailView, so that it will appear at the top. If the view already has a header view attached to it, it will be removed first.
`void removeHeaderView()` | Detaches the current header view if any, from the Navigation Rail.
The following methods can be used to manipulate the header view at runtime.
**Method** | **Description**
-------------------------------- | ---------------
`@Nullable view getHeaderView()` | Returns an instance of the header view associated with the Navigation Rail, null if none was currently attached.
### Adding badges
Rail icons can include badges on the upper right corner of the icon. Badges
convey dynamic information about the associated destination, such as counts or
status.
![Navigation rail with badges](assets/navigationrail/navigation-rail-badges.png)
Initialize and show a `BadgeDrawable` associated with `menuItemId`. Subsequent
calls to this method will reuse the existing `BadgeDrawable`:
```kt
var badge = navigationRail.getOrCreateBadge(menuItemId)
badge.isVisible = true
// An icon only badge will be displayed unless a number is set:
badge.number = 99
```
As best practice, if you need to temporarily hide the badge, for example until
the next notification is received, change the visibility of `BadgeDrawable`:
```kt
val badgeDrawable = navigationRail.getBadge(menuItemId)
if (badgeDrawable != null) {
badgeDrawable.isVisible = false
badgeDrawable.clearNumber()
}
```
To remove any `BadgeDrawable`s that are no longer needed:
```kt
navigationRail.removeBadge(menuItemId)
```
See the [`BadgeDrawable`](BadgeDrawable.md) documentation for more information.
## Navigation rail example
API and source code:
* `NavigationRailView`
* [Class description](https://developer.android.com/reference/com/google/android/material/navigationrail/NavigationRailView)
* [Class source](https://github.com/material-components/material-components-android/tree/master/lib/java/com/google/android/material/navigationrail/NavigationRailView.java)
The following example shows a navigation rail with four icons:
* Alarms
* Schedule
* Timers
* Stopwatch
In `navigation_rail_menu.xml` inside a `menu` resource directory:
```xml
<menu xmlns:android="http://schemas.android.com/apk/res/android">
<item
android:id="@+id/alarms"
android:enabled="true"
android:icon="@drawable/icon_alarm"
android:title="@string/alarms_destination_label"/>
<item
android:id="@+id/schedule"
android:enabled="true"
android:icon="@drawable/icon_clock"
android:title="@string/schedule_destination_label"/>
<item
android:id="@+id/timers"
android:enabled="true"
android:icon="@drawable/icon_sand_clock"
android:title="@string/timers_destination_label"/>
<item
android:id="@+id/stopwatch"
android:enabled="true"
android:icon="@drawable/icon_stop_watch"
android:title="@string/stopwatch_destination_label"/>
</menu>
```
In code:
```kt
navigationRail.selectedItemId = R.id.images
```
### Anatomy and key properties
The following is an anatomy diagram for the navigation rail:
![Navigation rail anatomy diagram](assets/navigationrail/navigation-rail-anatomy.png)
1. Container
2. Header - menu icon (optional)
3. Header - Floating action button (optional)
4. Icon - active
5. Active indicator
6. Label text - active (optional)
7. Icon - inactive
8. Label text - inactive (optional)
9. Large badge (optional)
10. Large badge label (optional)
11. Badge (optional)
#### Container attributes
**Element** | **Attribute** | **Related methods** | **Default value**
------------- | -------------------- | ------------------- | -----------------
**Color** | `app:backgroundTint` | N/A | `?attr/colorSurface`
**Elevation** | `app:elevation` | `setElevation` | `0dp`
#### Header attributes
**Element** | **Attribute** | **Related methods** | **Default value**
--------------- | ------------------ | ---------------------------------------------------------- | -----------------
**Header view** | `app:headerLayout` | `addHeaderView`<br/>`removeHeaderView`<br/>`getHeaderView` | N/A
See the
[FAB documentation](https://github.com/material-components/material-components-android/tree/master/docs/components/FloatingActionButton.md)
for more attributes.
#### Navigation item attributes
**Element** | **Attribute** | **Related methods** | **Default value**
------------------------- | ------------------------- | ----------------------------------------------------- | -----------------
**Menu resource** | `app:menu` | `inflateMenu`<br/>`getMenu` | N/A
**Ripple (inactive)** | `app:itemRippleColor` | `setItemRippleColor`<br/>`getItemRippleColor` | `?attr/colorPrimary` at 12% (see all [states](https://github.com/material-components/material-components-android/tree/master/lib/java/com/google/android/material/navigation/res/color/mtrl_navigation_bar_ripple_color.xml))
**Ripple (active)** | `app:itemRippleColor` | `setItemRippleColor`<br/>`getItemRippleColor` | `?attr/colorPrimary` at 12% (see all [states](https://github.com/material-components/material-components-android/tree/master/lib/java/com/google/android/material/navigation/res/color/mtrl_navigation_bar_ripple_color.xml))
**Label visibility mode** | `app:labelVisibilityMode` | `setLabelVisibilityMode`<br/>`getLabelVisibilityMode` | `LABEL_VISIBILITY_AUTO`
**Item minimum height** | `app:itemMinHeight` | `setItemMinimumHeight`<br/>`getItemMinimumHeight` | `NO_ITEM_MINIMUM_HEIGHT`
#### Active indicator attributes
**Element** | **Attribute** | **Related methods** | **Default value**
--------------------- | ---------------------- | ------------------------------------------------------------------------------------- | -----------------
**Color** | `android:color` | `setItemActiveIndicatorColor`<br/>`getItemActiveIndicatorColor` | `?attr/colorSecondaryContainer`
**Width** | `android:width` | `setItemActiveIndicatorWidth`<br/>`getItemActiveIndicatorWidth` | `56dp`
**Height** | `android:height` | `setItemActiveIndicatorHeight`<br/>`setItemActiveIndicatorHeight` | `32dp`
**Shape** | `app:shapeAppearance` | `setItemActiveIndicatorShapeAppearance`<br/>`getItemActiveIndicatorShapeAppearance` | `50% rounded`
**Margin horizontal** | `app:marginHorizontal` | `setItemActiveIndicatorMarginHorizontal`<br/>`getItemActiveIndicatorMarginHorizontal` | `4dp`
#### Icon attributes
**Element** | **Attribute** | **Related methods** | **Default value**
-------------------- | ------------------------------------- | ---------------------------------------------------------------- | -----------------
**Icon** | `android:icon` in the `menu` resource | N/A | N/A
**Size** | `app:itemIconSize` | `setItemIconSize`<br/>`setItemIconSizeRes`<br/>`getItemIconSize` | `24dp`
**Color (inactive)** | `app:itemIconTint` | `setItemIconTintList`<br/>`getItemIconTintList` | `?attr/colorOnSurfaceVariant`
**Color (active)** | `app:itemIconTint` | `setItemIconTintList`<br/>`getItemIconTintList` | `?attr/colorOnSecondaryContainer`
#### Text label attributes
**Element** | **Attribute** | **Related methods** | **Default value**
------------------------- | -------------------------------------- | ------------------------------------------------------------------- | -----------------
**Text label** | `android:title` in the `menu` resource | N/A | N/A
**Color (inactive)** | `app:itemTextColor` | `setItemTextColor`<br/>`getItemTextColor` | `?attr/colorOnSurfaceVariant`
**Color (active)** | `app:itemTextColor` | `setItemTextColor`<br/>`getItemTextColor` | `?attr/colorOnSurface`
**Typography (inactive)** | `app:itemTextAppearanceInactive` | `setItemTextAppearanceInactive`<br/>`getItemTextAppearanceInactive` | `?attr/textAppearanceTitleSmall`
**Typography (active)** | `app:itemTextAppearanceActive` | `setItemTextAppearanceActive`<br/>`getItemTextAppearanceActive` | `?attr/textAppearanceTitleSmall`
#### Styles
**Element** | **Style** | **Container color** | **Icon/Text label color (inactive)** | **Icon/Text label color (active)**
----------------- | ------------------------------------- | -------------------- | ------------------------------------ | ----------------------------------
**Default style** | `Widget.Material3.NavigationRailView` | `?attr/colorSurface` | `?attr/colorOnSurfaceVariant` | `?attr/colorOnSurface`<br/>`?attr/colorOnSecondaryContainer`
Default style theme attribute: `?attr/navigationRailStyle`
See the full list of
[styles](https://github.com/material-components/material-components-android/tree/master/lib/java/com/google/android/material/navigationrail/res/values/styles.xml),
[navigation bar attributes](https://github.com/material-components/material-components-android/tree/master/lib/java/com/google/android/material/navigation/res/values/attrs.xml),
and
[navigation rail attributes](https://github.com/material-components/material-components-android/tree/master/lib/java/com/google/android/material/navigationrail/res/values/attrs.xml).
## Theming a navigation rail
Navigation rail supports
[Material Theming](https://material.io/components/navigation-rail#theming),
which can customize color and typography.
### Navigation rail theming example
API and source code:
* `NavigationRailView`
* [Class description](https://developer.android.com/reference/com/google/android/material/navigationrail/NavigationRailView)
* [Class source](https://github.com/material-components/material-components-android/tree/master/lib/java/com/google/android/material/navigationrail/NavigationRailView.java)
The following example shows a navigation rail with Material Theming.
![Navigation rail theming example](assets/navigationrail/navigation-rail-theming.png)
#### Implementing navigation rail theming
Use theme attributes and a style in `res/values/styles.xml` which apply to all
navigation rails and affect other components:
```xml
<style name="Theme.App" parent="Theme.Material3.*">
...
<item name="colorPrimary">@color/shrine_theme_light_primary</item>
<item name="colorSecondaryContainer">@color/shrine_theme_light_secondaryContainer</item>
<item name="colorOnSecondaryContainer">@color/shrine_theme_light_onSecondaryContainer</item>
<item name="colorTertiaryContainer">@color/shrine_theme_light_tertiaryContainer</item>
<item name="colorOnTertiaryContainer">@color/shrine_theme_light_onTertiaryContainer</item>
<item name="colorError">@color/shrine_theme_light_error</item>
<item name="colorErrorContainer">@color/shrine_theme_light_errorContainer</item>
<item name="colorOnError">@color/shrine_theme_light_onError</item>
<item name="colorOnErrorContainer">@color/shrine_theme_light_onErrorContainer</item>
<item name="colorSurface">@color/shrine_theme_light_surface</item>
<item name="colorOnSurface">@color/shrine_theme_light_onSurface</item>
<item name="colorOnSurfaceVariant">@color/shrine_theme_light_onSurfaceVariant</item>
</style>
```
Use a default style theme attribute, styles, and a theme overlay, which apply to
all navigation rails but do not affect other components:
```xml
<style name="Theme.App" parent="Theme.Material3.*">
...
<item name="navigationRailStyle">@style/Widget.App.NavigationRailView</item>
</style>
<style name="Widget.App.NavigationRailView" parent="Widget.Material3.NavigationRailView">
<item name="materialThemeOverlay">@style/ThemeOverlay.App.NavigationRailView</item>
</style>
<style name="ThemeOverlay.App.NavigationRailView" parent="">
<item name="colorPrimary">@color/shrine_theme_light_primary</item>
<item name="colorSecondaryContainer">@color/shrine_theme_light_secondaryContainer</item>
<item name="colorOnSecondaryContainer">@color/shrine_theme_light_onSecondaryContainer</item>
<item name="colorTertiaryContainer">@color/shrine_theme_light_tertiaryContainer</item>
<item name="colorOnTertiaryContainer">@color/shrine_theme_light_onTertiaryContainer</item>
<item name="colorError">@color/shrine_theme_light_error</item>
<item name="colorErrorContainer">@color/shrine_theme_light_errorContainer</item>
<item name="colorOnError">@color/shrine_theme_light_onError</item>
<item name="colorOnErrorContainer">@color/shrine_theme_light_onErrorContainer</item>
<item name="colorSurface">@color/shrine_theme_light_surface</item>
<item name="colorOnSurface">@color/shrine_theme_light_onSurface</item>
<item name="colorOnSurfaceVariant">@color/shrine_theme_light_onSurfaceVariant</item>
</style>
```
Or use the style in the layout, which affects only this specific navigation rail
bar:
```xml
<com.google.android.material.navigationrail.NavigationRailView
...
style="@style/Widget.App.NavigationRailView"
/>
```