AppFunctionStringValueConstraint

Artifact: androidx.appfunctions:appfunctions

Kotlin |Java

@Retention(value = AnnotationRetention.BINARY)
@Target(allowedTargets = [AnnotationTarget.FUNCTION, AnnotationTarget.PROPERTY, AnnotationTarget.VALUE_PARAMETER])
annotation AppFunctionStringValueConstraint

Specifies constraints applied on the string values for return types, parameters, or properties in app functions.

This annotation can be applied to:

functions annotated with @AppFunctionDeclaration (to constrain the return value),
parameters of @AppFunctionDeclaration,
or properties within an @AppFunctionSerializable.

Usage Example:

// Constraining a function return value:
@AppFunctionDeclaration(isDescribedByKDoc = false)
@AppFunctionStringValueConstraint(enumValues = ["LOW", "MEDIUM", "HIGH"])
fun getPriorityLevel(): String {
    // Function body
}

// Constraining a parameter:
@AppFunctionDeclaration(isDescribedByKDoc = false)
fun setMode(
    @AppFunctionStringValueConstraint(enumValues = ["AUTO", "MANUAL"])
    mode: String
) {
    // Function body
}

// Constraining a property within an AppFunctionSerializable:
@AppFunctionSerializable(isDescribedByKDoc = false)
data class AppConfig(
    @property:AppFunctionStringValueConstraint(enumValues = ["ENABLED", "DISABLED"])
    val featureFlag: String
)

Summary

Public constructors
`AppFunctionStringValueConstraint( enumValues: Array<String>, patternMatchers: Array<AppFunctionPatternMatcher>, format: String )`

Public properties
`Array<String>`	`enumValues` The list of allowed string values for the annotated element.
`String`	`format` The format description for string values (e.g. `"uri"`).
`Array<AppFunctionPatternMatcher>`	`patternMatchers` The patterns that string values must match.

Public constructors

AppFunctionStringValueConstraint

Added in 1.0.0-beta01

AppFunctionStringValueConstraint(
    enumValues: Array<String> = [],
    patternMatchers: Array<AppFunctionPatternMatcher> = [],
    format: String = ""
)

Public properties

enumValues

val enumValues: Array<String>

The list of allowed string values for the annotated element.

These values are communicated to the agent or framework that interprets or invokes the @AppFunctionDeclaration. If any of the values carry special meaning (e.g., "AUTO" means automatic mode), such meanings should be documented clearly in the corresponding property, parameter, or function return KDoc.

format

val format: String

The format description for string values (e.g. "uri"). An empty string indicates no format description is set.

patternMatchers

val patternMatchers: Array<AppFunctionPatternMatcher>

The patterns that string values must match. A value is valid if it matches any of the patterns. An empty array indicates no pattern constraint is applied.

Each pattern is translated to a android.os.PatternMatcher in androidx.appfunctions.metadata.AppFunctionStringTypeMetadata.patternMatchers.

Important: Patterns are not validated at compile time. If android.os.PatternMatcher rejects any pattern (for example, a malformed android.os.PatternMatcher.PATTERN_ADVANCED_GLOB), the function using it is omitted from agents' search results. If the pattern is on a property of an AppFunctionSerializable, all of the app's functions are omitted.