display-glasses-with-jetpack-compose-glimmer — Android XR skill
Guidelines for building projected Android XR apps on display glasses with Jetpack Compose Glimmer: theming, focus and additive display behaviour.
npx skills add android/skills --skill display-glasses-with-jetpack-compose-glimmer -a claude-codeWhat display-glasses-with-jetpack-compose-glimmer does
This skill keeps an agent inside the rules for projected Android XR apps that render onto eyewear with a private in-lens display. It ships a glossary, dependency requirements and the constraints that trip people up first. Without it, an agent will happily reach for Material 3 in a place where it does not belong.
Material 3 is off the table here: no MaterialTheme, no androidx.compose.material3.* components inside a projected activity. Use GlimmerTheme and androidx.xr.glimmer.*, and always hand createGoogleSansFlexTypography() from androidx.xr.glimmer.googlefonts to the typography parameter. Shadows and elevation modifiers from Material 3 have no support either — ShadowScope and Depth tokens cover that ground.
Setup has hard floors. compileSdk must be 37 or higher, and the artifacts androidx.xr.glimmer:glimmer, androidx.xr.glimmer:glimmer-google-fonts and androidx.xr.projected:projected need at least 1.0.0-alpha21 and 1.0.0-alpha13. Check gradle/libs.versions.toml before writing versions by hand; catalog aliases are the safer route when they already exist. On an additive display black is fully transparent, so the root container takes Modifier.background(Color.Black) explicitly. Text below 18sp stops being readable, and Thin or Hairline weights shimmer on the lens.
What it helps with
- scaffold a projected activity for display glasses
- move a UI off Material 3 onto Glimmer components
- wire up GlimmerTheme and Google Sans Flex typography
- pick a readable text size for an in-lens display
- gate a launch button on whether the glasses are connected
Example prompts for the agent
- Create a projected activity for display glasses and wrap the content in GlimmerTheme with createGoogleSansFlexTypography()
- Check gradle/libs.versions.toml for the Glimmer artifacts and bump compileSdk to 37
- Add a "Launch on Glasses" button that stays disabled until ProjectedContext.isProjectedDeviceConnected returns true
How to install display-glasses-with-jetpack-compose-glimmer
1Skills CLI (Vercel)
npx skills add android/skills --skill display-glasses-with-jetpack-compose-glimmer -a claude-code2Manually: put the files in place
~/.claude/skills/display-glasses-with-jetpack-compose-glimmer/SKILL.mdCopy the whole skill folder; for one project use .claude/skills/display-glasses-with-jetpack-compose-glimmer/
1Skills CLI (Vercel)
npx skills add android/skills --skill display-glasses-with-jetpack-compose-glimmer -a codex2Manually: put the files in place
.agents/skills/display-glasses-with-jetpack-compose-glimmer/SKILL.mdFor all projects use ~/.agents/skills/
1Skills CLI (Vercel)
npx skills add android/skills --skill display-glasses-with-jetpack-compose-glimmer -a cursor2Manually: put the files in place
.cursor/skills/display-glasses-with-jetpack-compose-glimmer/SKILL.mdCursor also reads .agents/skills/ and .claude/skills/
1GitHub CLI
gh skill install android/skills display-glasses-with-jetpack-compose-glimmer2Manually: put the files in place
.github/skills/display-glasses-with-jetpack-compose-glimmer/SKILL.md1Skills CLI (Vercel)
npx skills add android/skills --skill display-glasses-with-jetpack-compose-glimmer -a gemini-cli2Platform CLI
gemini skills install https://github.com/android/skills --path xr/display-glasses-with-jetpack-compose-glimmerManually: put the files in place
.devin/skills/display-glasses-with-jetpack-compose-glimmer/SKILL.mdThe legacy .windsurf/skills/ path still works
Skills CLI (Vercel)
npx skills add android/skills --skill display-glasses-with-jetpack-compose-glimmer -a opencodeClaude.ai
Zip the folder and upload it in Settings → Capabilities → Skills
Step by step, with commands for each platform: How to install skills in Claude Code: five ways
Questions about display-glasses-with-jetpack-compose-glimmer
How do I install display-glasses-with-jetpack-compose-glimmer in Claude Code?
Run npx skills add android/skills --skill display-glasses-with-jetpack-compose-glimmer -a claude-code. The skill lands at ~/.claude/skills/display-glasses-with-jetpack-compose-glimmer/SKILL.md.
What does display-glasses-with-jetpack-compose-glimmer do?
It gives an agent the rules for projected Android XR apps on display glasses: GlimmerTheme setup, initial focus, background handling on additive displays and typography limits.
Does it cover audio-only glasses or Android XR headsets?
No. Audio-only eyewear and headsets using spatial panels or 3D volumes go through Jetpack Compose for XR instead.
Source text
SKILL.md · Apache-2.0
---
name: display-glasses-with-jetpack-compose-glimmer
description: Provides guidelines for developing projected Android XR apps for display
glasses using the Jetpack Compose Glimmer UI toolkit. Covers Glimmer design principles,
workflows, and interaction models for the glasses form factor. Use this skill to
build an Android XR Augmented Experience app with Jetpack Compose Glimmer. Don't
use for audio-only AI glasses without a display, non-glasses Android XR headsets
(spatial panels or 3D volumes with Jetpack Compose for XR), or phone and tablet
Material 3 UIs.
license: Complete terms in LICENSE.txt
metadata:
author: Google LLC
last-updated: '2026-10-22'
keywords:
- Jetpack Compose Glimmer
- display glasses
- Projected Activity
- GlimmerTheme
- Additive Display
- Android XR - Augmented Experiences
---
## Glossary
| Term | Definition |
|---|---|
| **Intelligent eyewear** | Hands-free eyewear with speakers, camera, and microphone (audio-only or display glasses). |
| **Display glasses** | Eyewear with a private in-lens display for glanceable visuals that pair with audio. |
| **Jetpack Compose Glimmer** | Compose UI toolkit providing components, theming, and focus behavior for display glasses. |
| **Projected activity** | An `Activity` running on a phone host whose UI and input are projected to connected eyewear. |
| **Projected device** | An XR eyewear device connected to an Android host phone that projects app content to it. |
| **GlimmerTheme** | Root styling provider for `GlimmerColors`, `GlimmerTypography`, and `GlimmerShapes`. |
| **Additive display** | Display where black (`#000000`) renders as 100% transparent by adding light to the scene. |
| **Augmented experiences** | Lightweight, additive Android XR experiences that help users while they're on the go. |
| **Visual angle** | Perceived size in XR; minimum readable text is 0.6 degrees (about 18sp at 1 m). |
## Prerequisites
- Target `compileSdk` 37 or higher (`compileSdk = 37` or `compileSdk { version
= release(37) }`). Update `compileSdk` to 37 if lower.
- When adding dependencies, follow the instructions in [Create your first
activity for intelligent eyewear](https://developer.android.com/develop/xr/jetpack-xr-sdk/ai-glasses/first-activity):
- `androidx.xr.glimmer:glimmer` (minimum `1.0.0-alpha21`, or catalog alias `libs.androidx.glimmer`)
- `androidx.xr.glimmer:glimmer-google-fonts` (minimum `1.0.0-alpha21`, or catalog alias `libs.androidx.glimmer.google.fonts`)
- `androidx.xr.projected:projected` (minimum `1.0.0-alpha13`, or catalog alias `libs.androidx.xr.projected` or `libs.androidx.projected`)
- Check `gradle/libs.versions.toml` first; if catalog entries exist, use them in `app/build.gradle.kts` and verify their versions meet the minimums. Never guess `1.0.0-alpha01` for `glimmer-google-fonts`.
## Core constraints and limitations
- **Don't** : Use `MaterialTheme` or Material 3 components (`androidx.compose.material3.*`) inside Projected Activities or Glimmer UI.
- **Do** : Use `GlimmerTheme` and Glimmer components (`androidx.xr.glimmer.*`).
- **Do** : Always pass `createGoogleSansFlexTypography()` from `androidx.xr.glimmer.googlefonts` as `typography` in `GlimmerTheme`.
- Specific hardware device models or unique capabilities aren't detailed.
- **Elevation** : Material 3 shadow or elevation modifiers aren't supported. Use `ShadowScope` or `Depth` tokens from Jetpack Compose Glimmer.
- **Typography limits**: Minimum readable text size is 18sp (0.6°). Avoid "Thin" or "Hairline" weights, which shimmer on additive lenses.
## 1. Set up dependencies
- **Set up projected activity** : When creating a projected activity, follow
[Create your first activity for intelligent eyewear](https://developer.android.com/develop/xr/jetpack-xr-sdk/ai-glasses/first-activity) and
[projectedcontext-source.md](references/projectedcontext-source.md). Set `android:requiredDisplayCategory` to
`android.hardware.display.category.XR_PROJECTED` in `AndroidManifest.xml`:
```xml
<activity
android:name="com.example.xr.projected.ProjectedMainActivity"
android:exported="true"
android:requiredDisplayCategory="android.hardware.display.category.XR_PROJECTED">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.XR_PROJECTED_LAUNCHER"/>
</intent-filter>
</activity>
```
<br />
- **Mobile app integration** : In the host phone app, add a button with
`Text("Launch on Glasses")`. Observe
`ProjectedContext.isProjectedDeviceConnected(context, coroutineContext)`
using
`collectAsStateWithLifecycle(initialValue = false)` to set the button's
`enabled` state so it's disabled when glasses are disconnected. When
clicked, launch `GlassesMainActivity` on the glasses display using
`ProjectedContext.createProjectedActivityOptions(context).toBundle()` as
shown in the following snippet:
```kotlin
val options = ProjectedContext.createProjectedActivityOptions(context)
val intent = Intent(context, ProjectedMainActivity::class.java)
context.startActivity(intent, options.toBundle())
```
<br />
- **UI library and font** : When declaring the Glimmer, Google Fonts, and
Projected artifacts in `app/build.gradle.kts`, follow [Declaring Jetpack
Compose Glimmer Dependencies](https://developer.android.com/jetpack/androidx/releases/xr-glimmer), and follow
[glimmersansflextypography-source.md](references/glimmersansflextypography-source.md) when configuring Google Sans Flex
using `createGoogleSansFlexTypography`.
- **Theming, initial focus, and black background** : On additive displays, pure
black (`Color.Black` or `GlimmerTheme.colors.background`) renders as 100%
transparent. In `onCreate` (annotated with
`@OptIn(ExperimentalComposeUiApi::class)`), set
`ComposeUiFlags.isInitialFocusOnFocusableAvailable = true`
(`androidx.compose.ui.ComposeUiFlags`), wrap content in
`GlimmerTheme(typography = createGoogleSansFlexTypography())`, and apply
`Modifier.background(Color.Black)` (or `GlimmerTheme.colors.background`) to
the root container:
```kotlin
@OptIn(ExperimentalProjectedApi::class)
class ProjectedMainActivity : ComponentActivity() {
private var displayController: ProjectedDisplayController? = null
private var isVisualUiSupported by mutableStateOf(false)
private var areVisualsOn by mutableStateOf(true)
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
lifecycle.addObserver(object : DefaultLifecycleObserver {
override fun onDestroy(owner: LifecycleOwner) {
displayController?.close()
displayController = null
}
})
initializeGlassesFeatures()
setContent {
GlimmerTheme {
HomeScreen(
areVisualsOn = areVisualsOn,
isVisualUiSupported = isVisualUiSupported,
onClose = { finish() }
)
}
}
}
private fun initializeGlassesFeatures() {
lifecycleScope.launch {
// Check device capabilities
val projectedDeviceController = ProjectedDeviceController.create(this@ProjectedMainActivity)
isVisualUiSupported = projectedDeviceController.capabilities.contains(CAPABILITY_VISUAL_UI)
val controller = ProjectedDisplayController.create(this@ProjectedMainActivity)
displayController = controller
val observer = GlassesLifecycleObserver(
context = this@ProjectedMainActivity,
controller = controller,
onVisualsChanged = { visualsOn -> areVisualsOn = visualsOn }
)
lifecycle.addObserver(observer)
}
}
}
```
<br />
- **Hardware capabilities, permissions, and access** : When checking hardware
capabilities, requesting permissions, or accessing glasses hardware, follow
[Check device capabilities at runtime](https://developer.android.com/develop/xr/jetpack-xr-sdk/ai-glasses/check-capabilities), [Request hardware
permissions](references/android/develop/xr/jetpack-xr-sdk/request-hardware-permissions.md), and [Use a projected context to access hardware](references/android/develop/xr/jetpack-xr-sdk/access-hardware-projected-context.md).
## 2. Minimize and translate the UI
- Build UI with Jetpack Compose Glimmer components and use depth for priority.
- Design from the bottom up and always bottom-align UI (`Alignment.BottomCenter`).
- **One thing at a time** : Show one primary piece of information at a time (for example, using `VerticalStack`) and avoid multiple simultaneous cards.
- **Color contrast** : When choosing colors, follow [material-hct-source.md](references/material-hct-source.md) to maintain at least a 70% tone difference between foreground and background in HCT.
## 3. Map input controls
- Map tap and swipe interactions to the glasses touchpad. Inputs are one-dimensional; avoid nesting scrolling controls.
- Use System Back to dismiss temporary states or detailed views.
- When implementing focus navigation and hardware input handling, follow [Focus in Jetpack Compose Glimmer](references/android/develop/xr/jetpack-xr-sdk/jetpack-compose-glimmer/focus.md) and [Hardware Controls for display
glasses](references/android/design/ui/ai-glasses/guides/interaction/inputs.md). Focus movement is continuous for scrollable containers and discrete for elements like button rows.
## 4. Build with Jetpack Compose Glimmer
### Implementing Glimmer styles
When accessing theme tokens using `GlimmerTheme`, follow
[glimmertheme-source.md](references/glimmertheme-source.md).
| Category | Token | Value / Role |
|---|---|---|
| **Color** | primary / secondary | `#9BBFFF` / `#4C88E9` (Focal colors) |
| **Color** | positive / negative | `#7AD48F` (Confirmation) / `#F57082` (Alert) |
| **Color** | background | `#000000` (Pure black, renders 100% transparent) |
| **Color** | surface | `#262626` (Use `SurfaceDefaults.border` for borders) |
| **Shape** | Standard / Small | `RoundedCornerShape(36.dp)` / `RoundedCornerShape(12.dp)` |
#### Typography scale (Google Sans Flex) and depth levels
Use Google Sans Flex with variable axes `ROND` = `100f`, `wdth` = `100f`, `opsz`
= `9f`, and `wght` by role:
| Style | Size / Line-Height | Weight |
|---|---|---|
| **Title Large / Medium / Small** | 30/36.sp, 24/32.sp, 20/28.sp | 725 |
| **Body Large / Medium / Small** | 30/36.sp, 24/32.sp, 20/28.sp | 520 |
| **Caption** | 18.sp / 28.sp | 650 |
When simulating depth with `DepthEffect` and `DepthEffectLevels`, follow
[deptheffect-source.md](references/deptheffect-source.md) and [deptheffectlevels-source.md](references/deptheffectlevels-source.md): use `level1`
for resting cards and background UI, and `level2` for focused or pressed
interactive UI.
### Implementing Jetpack Compose Glimmer components
#### Cards, ActionCards, ImageCards, and ButtonGroups
Cards (`androidx.xr.glimmer.Card`) group related content into a single focal
point. Never embed a `Card` within a `ListItem`. When implementing cards, follow
the instructions in [Jetpack Compose Glimmer: Cards](references/android/develop/xr/jetpack-xr-sdk/jetpack-compose-glimmer/cards.md), [card-source.md](references/card-source.md),
and [card-samples-source.md](references/card-samples-source.md).
- **Clickable versus non-clickable card** : Pass `onClick = { ... }` if the entire `Card` acts as a trigger; omit `onClick` if informational. Control focus on non-clickable cards with `focusable: Boolean = true` (such as `Card(focusable = false)`).
- **Single primary action (`ActionCard`)** : When a card has a single primary
button action anchored to its bottom edge, use
`androidx.xr.glimmer.ActionCard` instead of placing a `Button` inside
`Card`. Its `action` button takes focus directly:
```kotlin
ActionCard(
action = {
Button(onClick = {}, trailingIcon = { Icon(FavoriteIcon, "Localized description") }) {
Text("Send")
}
}
) {
Text("This is a card with a title, leading icon, header image, and action")
}
```
<br />
- **Multiple actions (`Card` and `ButtonGroup`)---avoiding focus contention** :
When pairing a card with multiple action buttons, use
`androidx.xr.glimmer.ButtonGroup` (with optional
`rememberButtonGroupState`). **Never nest `ButtonGroup` inside `Card { ...
}`.** Place a non-focusable `Card(focusable = false)` (without `onClick`)
**above** `ButtonGroup` as a sibling in a `Column` so the card and buttons
don't compete for focus:
```kotlin
ButtonGroup(modifier = Modifier.fillMaxWidth()) {
Button(onClick = {}) { Text("Button 1") }
Button(onClick = {}) { Text("Button 2") }
Button(onClick = {}) { Text("Button 3") }
Button(onClick = {}) { Text("Button 4") }
Button(onClick = {}) { Text("Button 5") }
}
```
<br />
- **Image cards** : Use `ImageCard`, `LeadingImageCard`, or `TrailingImageCard`
to display prominent imagery alongside card text.
#### Buttons and ToggleButtons
When implementing buttons or toggle buttons, follow the instructions in [Jetpack
Compose Glimmer: Buttons](references/android/develop/xr/jetpack-xr-sdk/jetpack-compose-glimmer/buttons.md), [button-source.md](references/button-source.md), and
[button-samples-source.md](references/button-samples-source.md).
- **Standard and icon buttons** : Use `Button` for text actions (with optional `leadingIcon`/`trailingIcon`) and `IconButton` for icon-only triggers (such as media next-track or previous-track buttons).
- **Toggle buttons (`ToggleButton` and `IconToggleButton`)** : Use
`ToggleButton` or `IconToggleButton` for stateful on/off or play/pause
controls that morph based on `checked`:
```kotlin
@Composable
fun ToggleButtonWithLeadingIconSample() {
var checked by remember { mutableStateOf(false) }
ToggleButton(
checked = checked,
leadingIcon = {
Icon(
if (checked) FavoriteIcon else OutlinedFavoriteIcon,
contentDescription = "Toggle favorite"
)
},
onCheckedChange = { checked = it }
) {
Text(if (checked) "On" else "Off")
}
}
```
<br />
#### Title chips
`TitleChip` (`androidx.xr.glimmer.TitleChip`) is a non-interactive pill header
(three words or fewer, single line). When implementing title chips, follow the
instructions in [Jetpack Compose Glimmer: Title Chips](references/android/develop/xr/jetpack-xr-sdk/jetpack-compose-glimmer/title-chips.md),
[titlechip-source.md](references/titlechip-source.md), and [titlechip-samples-source.md](references/titlechip-samples-source.md).
- **Spatial spacing** : When placing a standalone `TitleChip` above a `Card` or
`ActionCard`, center the `TitleChip` horizontally and separate it from the
card using `TitleChipDefaults.associatedContentSpacing` (using `Spacer` or
`Arrangement.spacedBy(TitleChipDefaults.associatedContentSpacing)`):
```kotlin
@Composable
fun TitleChipWithCardSample() {
Column(horizontalAlignment = Alignment.CenterHorizontally) {
TitleChip { Text("Title Chip") }
Spacer(Modifier.height(TitleChipDefaults.associatedContentSpacing))
Card(
title = { Text("Title") },
subtitle = { Text("Subtitle") },
leadingIcon = { Icon(FavoriteIcon, "Localized description") },
) {
Text("Card Content")
}
}
}
```
<br />
#### Icons
When adding icons or icon buttons, follow the instructions in [Jetpack Compose
Glimmer: Icons](references/android/develop/xr/jetpack-xr-sdk/jetpack-compose-glimmer/icons.md), [icon-source.md](references/icon-source.md), [iconbutton-source.md](references/iconbutton-source.md), and
[iconsizes-source.md](references/iconsizes-source.md).
- **Sizing and interactivity** : Size icons with `GlimmerTheme.iconSizes` (`small`, `medium`, `large`). Use `IconButton` or `IconToggleButton` for triggers and `Icon` for status indicators.
- **Contrast and library** : **Never** use pure black (`Color.Black`) for icon tints; black renders as transparent. Use [Material Symbols](https://fonts.google.com/icons?icon.style=Rounded) (600 weight, Rounded, Unfilled). If `androidx.compose.material:material-icons-*` isn't in `app/build.gradle.kts`, build vectors with `ImageVector.Builder` or `painterResource` instead of importing `androidx.compose.material.icons.*`.
#### Lists
Use `GlimmerLazyColumn` (`androidx.xr.glimmer.list.GlimmerLazyColumn`) for
homogeneous scrollable items. When building scrollable lists and list items,
follow the API definitions in [list-source.md](references/list-source.md), [listitem-source.md](references/listitem-source.md),
and [liststate-source.md](references/liststate-source.md).
- **Always use `GlimmerLazyColumn`** : Never use foundation `LazyColumn`. Import `GlimmerLazyColumn`, `rememberGlimmerLazyListState`, and `items` from `androidx.xr.glimmer.list` (`item` is a scope member, not imported). For programmatic scrolling to the first item, hoist `val listState =
rememberGlimmerLazyListState()` and call `listState.scrollToItem(0)` or `listState.animateScrollToItem(0)`.
- **Integrated title, spacing, and rows** : Pass headers using `title = {
TitleChip { Text("...") } }` directly on `GlimmerLazyColumn` (not outside
it), set `verticalArrangement = Arrangement.spacedBy(20.dp)`, and render
rows with `androidx.xr.glimmer.ListItem(onClick = { ... }, supportingLabel =
{ Text(...) }) { Text(...) }` (pass the primary label as the trailing
`content` lambda, not `headlineContent`, and never nest a `Card` inside
`ListItem`):
```kotlin
@Composable
fun GlimmerLazyColumnWithTitleChipSample() {
val ingredientItems =
listOf("Milk", "Flour", "Egg", "Salt", "Apples", "Butter", "Vanilla", "Sugar", "Cinnamon")
GlimmerLazyColumn(title = { TitleChip { Text("Ingredients") } }) {
items(ingredientItems) { text -> ListItem { Text(text) } }
}
}
```
<br />
#### Stacks
Use `VerticalStack` (`androidx.xr.glimmer.stack.VerticalStack`) to display
heterogeneous cards one at a time (such as calendar, transit, and weather
cards). **Never** use a `TitleChip` with `VerticalStack`. When implementing a
`VerticalStack`, follow the API definitions in [stack-source.md](references/stack-source.md),
[stackstate-source.md](references/stackstate-source.md), and [stackitemscope-source.md](references/stackitemscope-source.md).
- **Bottom alignment, height (+66.dp), and `itemDecoration`** : Align
`VerticalStack` to `Alignment.BottomCenter`, set its height to **`66.dp`
taller than the tallest card** (`maxCardHeight + 66.dp`), and apply
`Modifier.itemDecoration(CardDefaults.shape)` to the `Card` inside every
`item { ... }` block so background cards are clipped and masked:
```kotlin
@Composable
fun VerticalStackSample() {
VerticalStack {
item {
Card { Text("Top Card") }
}
item {
Card { Text("Second Card") }
}
item {
Card { Text("Third Card") }
}
}
}
```
<br />
#### Horizontal pagers and animated text
Use `GlimmerHorizontalPager`
(`androidx.xr.glimmer.pager.GlimmerHorizontalPager`) with
`rememberGlimmerPagerState(pageCount = { ... })` for horizontal card
walkthroughs (never foundation `HorizontalPager`).
- **Smooth text motion** : Inside pager pages, configure Glimmer [`Text`](references/android/develop/xr/jetpack-xr-sdk/jetpack-compose-glimmer/text.md)
(`androidx.xr.glimmer.Text`, never `androidx.compose.material3.Text`) with
`textMotion = TextMotion.Animated` (using `.copy(textMotion =
TextMotion.Animated)`) for smooth rendering during snap transitions:
```kotlin
// Hoist the pager state, specifying the total page count with a lambda.
val pagerState = rememberGlimmerPagerState(pageCount = { 10 })
GlimmerHorizontalPager(
state = pagerState,
modifier = Modifier.fillMaxSize(),
) { page ->
// Use Glimmer components like Card and Text for optimized glasses styling.
Card(modifier = Modifier.fillMaxWidth()) {
Text(
text = "Page: $page",
// Recommended: use TextMotion.Animated for smooth transitions in a pager.
style = LocalTextStyle.current.copy(textMotion = TextMotion.Animated),
)
}
}
```
<br />
#### Surface
`Modifier.surface` (`androidx.xr.glimmer.surface`) builds custom interactive
components (such as status badges without `Card` or `Button`). When creating
custom surfaces, follow the API definitions in [surface-source.md](references/surface-source.md).
- **Shared `MutableInteractionSource` and order** : Create a single `remember {
MutableInteractionSource() }` and pass it to both
`Modifier.surface(interactionSource = interactionSource, ...)` and
`.clickable(interactionSource = interactionSource, ...)` (or `.focusable`),
chaining `.surface(...)` **before** `.clickable(...)`:
```kotlin
@Composable
fun FocusableSurfaceSample() {
val interactionSource = remember { MutableInteractionSource() }
Box(
modifier = Modifier
.size(100.dp)
.surface(interactionSource = interactionSource)
.focusable(interactionSource = interactionSource),
contentAlignment = Alignment.Center
) {
Text("Focusable")
}
}
@Composable
fun ClickableSurfaceSample() {
val interactionSource = remember { MutableInteractionSource() }
Box(
modifier = Modifier
.size(100.dp)
.surface(interactionSource = interactionSource)
.focusable(interactionSource = interactionSource)
.clickable(
interactionSource = interactionSource,
indication = null
) { /* Handle click action */ },
contentAlignment = Alignment.Center
) {
Text("Clickable")
}
}
```
<br />
#### Voice input indicator and indirect pointer gestures
- **`VoiceInputIndicator` and `ContainedVoiceInputIndicator`** : Pass a `level`
lambda returning a `Float` normalized to `0.0f..1.0f`. When driven by
`SpeechRecognizer` (`RecognitionListener.onRmsChanged(rmsdB: Float)`),
normalize and clamp `rmsdB` with `.coerceIn(0f, 1f)`:
```kotlin
// Example state variable to hold the normalized level (0.0 to 1.0)
// that the VoiceInputIndicator component expects.
val audioLevel = MutableStateFlow(0f)
// Initialize the Android SpeechRecognizer
val speechRecognizer = SpeechRecognizer.createSpeechRecognizer(context)
// Listener to capture speech events and audio level changes
val listener = object : RecognitionListener {
override fun onRmsChanged(rmsdB: Float) {
// Normalize raw dB level to a 0.0-1.0 range.
// Android SpeechRecognizer's rmsdB typically ranges from 0 to ~10.
audioLevel.value = ((rmsdB - 1f) / 9f).coerceIn(0f, 1f)
}
// ... Implement other required RecognitionListener methods ...
override fun onReadyForSpeech(params: Bundle?) {}
override fun onBeginningOfSpeech() {}
override fun onEndOfSpeech() {}
override fun onError(error: Int) {}
override fun onResults(results: Bundle?) {}
override fun onPartialResults(partialResults: Bundle?) {}
override fun onEvent(eventType: Int, params: Bundle?) {}
override fun onBufferReceived(buffer: ByteArray?) {}
}
// Attach the listener to the recognizer
speechRecognizer.setRecognitionListener(listener)
// Create an intent to specify the recognition model and behavior
val intent = Intent(RecognizerIntent.ACTION_RECOGNIZE_SPEECH).apply {
putExtra(RecognizerIntent.EXTRA_LANGUAGE_MODEL, RecognizerIntent.LANGUAGE_MODEL_FREE_FORM)
}
// Begin listening for audio input
speechRecognizer.startListening(intent)
```
<br />
```kotlin
@Composable
fun VoiceInputExample(modifier: Modifier) {
// Collect the flow as Compose State so the UI reacts to changes in real-time.
val currentLevel by audioLevel.collectAsState()
VoiceInputIndicator(
// The VoiceInputIndicator component provides a visual "pulse" or indicator
// that changes based on the 'level' lambda, which returns a Float between 0.0 and 1.0.
level = { currentLevel },
modifier = modifier
)
}
```
<br />
- **`Modifier.onIndirectPointerGesture`** : Handle low-level touchpad tap
(`onClick`), forward swipe (`onSwipeForward`), and backward swipe
(`onSwipeBackward`) gestures using
`androidx.xr.glimmer.onIndirectPointerGesture` on a container made
**focusable** (using `focusTarget`, `focusable`, or `surface(focusable =
true)`):
```kotlin
@Composable
fun OnIndirectPointerGestureSample() {
var lastGesture by remember { mutableStateOf("None") }
Box(
modifier =
Modifier.fillMaxSize()
.onIndirectPointerGesture(
enabled = true,
onSwipeForward = { lastGesture = "Forward" },
onSwipeBackward = { lastGesture = "Backward" },
onClick = { lastGesture = "Click" },
)
.focusTarget(),
contentAlignment = Alignment.Center,
) {
Text("Last Gesture: $lastGesture")
}
}
```
<br />
## 5. Integrate with system UI
- When handling notifications or starting a projected activity from a notification, follow the instructions in [Understand notification behavior
for intelligent eyewear](https://developer.android.com/develop/xr/jetpack-xr-sdk/ai-glasses/notifications/behavior) and [Start a glasses activity on display
glasses from a notification](https://developer.android.com/develop/xr/jetpack-xr-sdk/ai-glasses/notifications/start-activity).
© Google LLC · Apache-2.0 · android/skills