Preview

Artifact: androidx.wear.tiles:tiles-tooling-preview

Added in 1.3.0

Kotlin |Java

@Retention(value = AnnotationRetention.BINARY)
@Target(allowedTargets = [AnnotationTarget.ANNOTATION_CLASS, AnnotationTarget.FUNCTION])
@Repeatable
@MustBeDocumented
public annotation Preview

The annotation that marks Tile preview components that should have a visual preview in the Android Studio preview panel. Tile preview components are methods that take an optional Context parameter and return a TilePreviewData. Methods annotated with Preview must be top level declarations or in a top level class with a default constructor.

For example:

@Preview
fun myTilePreview(): TilePreviewData {
    return TilePreviewData { request -> myTile(request) }
}

or:

@Preview
fun myTilePreview(context: Context): TilePreviewData {
    return TilePreviewData { request -> myTile(request, context) }
}

Because of the way previews are rendered within Android Studio, they are lightweight and don't require the whole Android framework to render them. However, this comes with the following limitations:

No network access
No file access
Some Context APIs may not be fully available, such as launching activities or retrieving services

For more information, see https://developer.android.com/jetpack/compose/tooling/previews#preview-limitations

The annotation contains a number of parameters that allow to define the way the Tile will be rendered within the preview. The passed parameters are only read by Studio when rendering the preview.

Summary

Public constructors
`Preview( @NonNull String name, @NonNull String group, @NonNull String locale, @NonNull String device, @FloatRange(from = 0.01) float fontScale )`

Public methods
`final @NonNull String`	`getDevice()` Device identifier indicating the device to use in the preview.
`final float`	`getFontScale()` User preference for the linear scaling factor for fonts, relative to the base density scaling.
`final @NonNull String`	`getGroup()` Group name for this @`Preview`.
`final @NonNull String`	`getLocale()` Current user preference for the locale, corresponding to locale resource qualifier.
`final @NonNull String`	`getName()` Display name of this preview allowing to identify it in the panel.

Public constructors

Preview

public Preview(
    @NonNull String name,
    @NonNull String group,
    @NonNull String locale,
    @NonNull String device,
    @FloatRange(from = 0.01) float fontScale
)

Parameters
`@NonNull String name`	Display name of this preview allowing to identify it in the panel.
`@NonNull String group`	Group name for this @`Preview`. This allows grouping them in the UI and displaying only one or more of them.
`@NonNull String locale`	Current user preference for the locale, corresponding to locale resource qualifier. By default, the `default` folder will be used.
`@NonNull String device`	Device identifier indicating the device to use in the preview. For example "id:wearos_small_round".See the available devices in `WearDevices`.
`@FloatRange(from = 0.01) float fontScale`	User preference for the linear scaling factor for fonts, relative to the base density scaling.

Public methods

getDevice

public final @NonNull String getDevice()

Device identifier indicating the device to use in the preview. For example "id:wearos_small_round".See the available devices in WearDevices.

getFontScale

public final float getFontScale()

User preference for the linear scaling factor for fonts, relative to the base density scaling.

getGroup

public final @NonNull String getGroup()

Group name for this @Preview. This allows grouping them in the UI and displaying only one or more of them.

getLocale

public final @NonNull String getLocale()

Current user preference for the locale, corresponding to locale resource qualifier. By default, the default folder will be used.

getName

public final @NonNull String getName()

Display name of this preview allowing to identify it in the panel.