MainActivity

Overview

The MainActivity serves as the entry point for the MultiSet SDK demo application. It demonstrates SDK initialization, authentication handling, and navigation to the AR localization activity.

Description

This activity is responsible for:

1. Initializing the MultiSet SDK with credentials

2. Handling the authentication flow

3. Managing camera and ARCore permissions

4. Launching the unified MultiSetLocalizationActivity for single-frame or multi-frame localization

5. Launching ObjectTrackingActivity for AR object detection and tracking

The landing page uses a card-based layout:

• Settings Gear: top-right icon that opens the Settings dialog to edit localization & object-tracking configuration at runtime

• Auth Button: full-width, shows authentication state

• Localization Card: displays map code, a mode toggle (Single Frame / Multi Frame), and a Start Localization button

• Object Tracking Card: displays configured object codes and a Start Object Tracking button

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Authentication Flow

1. SDK Initialization

The SDK is initialized using credentials from BuildConfig:

val config = MultiSetSDKConfig.Builder(clientId, clientSecret)
    .mapCode(mapCode)           // or .mapSetCode(mapSetCode)
    .enableMeshVisualization(true)
    .backgroundLocalization(true)
    .build()

MultiSetSDK.initialize(this, config, this)

In the sample app this is wrapped by MultiSetSDKInit.initialize(context, callback), which reads the BuildConfig fields produced from multiset.properties, applies the optional MULTISET_BASE_URL override, and returns false (rather than throwing) when credentials or every map and object code are missing, so the UI can show a setup message.

2. Configuration Builder Options

Method	Description
mapCode(String)	Set a single map code for localization
mapSetCode(String)	Set a mapSet code for localizing against multiple maps
objectCodes(List<String>)	Set the object codes to track (maximum 10)
localizationMode(LocalizationMode)	SINGLE_FRAME or MULTI_FRAME
enableMeshVisualization(Boolean)	Enable/disable 3D mesh overlay visualization
backgroundLocalization(Boolean)	Enable/disable background localization
poseConsistencyCheck(Boolean)	Enable/disable false-positive rejection
poseConsistencyThreshold(Float)	Tolerance in metres, 3 to 30
baseUrl(String)	Point the SDK at a staging or on-premise API host

The builder exposes the full configuration surface, including confidence settings, localization hints, GPS options, frame counts and image quality. See LocalizationConfig for the meaning of each value.

3. Authentication Callbacks

The activity implements MultiSetSDKCallback to receive authentication events:

override fun onSDKReady() {
    // SDK is initialized, authentication in progress
}

override fun onAuthenticationSuccess() {
    // Authentication successful, ready for localization
    // Enable localization buttons
}

override fun onAuthenticationFailure(error: String) {
    // Authentication failed
    // Show error message and enable retry
}

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APIs Used for Authentication

MultiSetSDK

Method	Description
MultiSetSDK.initialize(context, config, callback)	Initializes the SDK with configuration and callback
MultiSetSDK.isAuthenticated()	Whether a valid token is currently held
MultiSetSDK.getVersion()	The SDK version string
MultiSetSDK.localizationSession(frameSource, mode)	Creates a localization session
MultiSetSDK.objectTrackingSession(frameSource, objectCodes)	Creates an object tracking session
MultiSetSDK.resetPoseConsistencyReference()	Re-bootstraps the false-positive reference anchor
MultiSetSDK.release()	Releases SDK resources

MultiSetSDK.getLastLocalizationResult() was removed in 1.16.0. Results are delivered through the session callbacks instead. See FrameSource and Sessions.

MultiSetSDKConfig.Builder

Method	Parameters	Description
Builder(clientId, clientSecret)	String, String	Creates a configuration builder with credentials
mapCode(code)	String	Sets the map code for single-map localization
mapSetCode(code)	String	Sets the mapSet code for multi-map localization
enableMeshVisualization(enabled)	Boolean	Enables mesh visualization after localization
backgroundLocalization(enabled)	Boolean	Enables background localization
build()	-	Builds the configuration object

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Structure

MainActivity is the landing screen. It initializes the SDK, reflects authentication state in the UI, and launches the two AR activities.

setupUI()

Initializes the UI components and sets up button click listeners:

• Mode toggle group (Single Frame / Multi Frame selection)

• Start Localization button

• Start Object Tracking button

• Settings gear (opens SettingsDialogFragment to edit LocalizationConfig / ObjectTrackingConfig at runtime)

Persisted configuration is restored before any AR activity reads it: MainActivity.onCreate() calls ConfigStore.load(this), which applies the values saved from the Settings dialog. Credentials and map / object codes are always sourced from multiset.properties and are never persisted.

displayMapCode() and displayObjectCodes()

Render the configured map (or mapSet) code and the object code list on the landing cards, so it is obvious which environment and objects the build is pointed at.

showConfigurationAlert()

Shown when MultiSetSDKInit.initialize() returns false, meaning credentials or all map and object codes are missing from multiset.properties.

Launching the AR activities

// Localization
val intent = Intent(this, MultiSetLocalizationActivity::class.java)
intent.putExtra(EXTRA_LOCALIZATION_MODE, selectedMode.name)
startActivity(intent)

// Object Tracking
val intent = Intent(this, ObjectTrackingActivity::class.java)
intent.putExtra(EXTRA_OBJECT_CODES, codes.toTypedArray())
startActivity(intent)

Camera permission and ARCore availability are requirements of the AR activities, which use ARCore through Sceneform. They are not requirements of the SDK itself.

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Callbacks (MultiSetSDKCallback Interface)

onSDKReady()

Called when the SDK has been initialized and is beginning authentication.

override fun onSDKReady() {
    runOnUiThread {
        binding.authButton.text = getString(R.string.authenticating)
    }
}

onAuthenticationSuccess()

Called when authentication with the MultiSet backend is successful. Enables the Localization and Object Tracking buttons and updates the auth button to show a green "Authenticated" state.

override fun onAuthenticationSuccess() {
    runOnUiThread {
        binding.authButton.text = getString(R.string.authenticated)
        binding.authButton.isEnabled = false
        binding.authButton.backgroundTintList = ColorStateList.valueOf(
            ContextCompat.getColor(this, R.color.success)
        )
        binding.localizationButton.isEnabled = true
        binding.objectTrackingButton.isEnabled = true
    }
}

onAuthenticationFailure(error: String)

Called when authentication fails.

Parameter	Type	Description
error	String	Error message describing the failure reason

override fun onAuthenticationFailure(error: String) {
    runOnUiThread {
        binding.statusText.text = "Authentication Failed"
        binding.authButton.isEnabled = true
        showToast("Authentication failed: $error")
    }
}

onLocalizationSuccess(result: LocalizationResult)

Called when localization succeeds. The result can be logged or used by the host application.

Parameter	Type	Description
result	LocalizationResult	Contains map code, map codes list, position, rotation, confidence, and optional geo-coordinates

override fun onLocalizationSuccess(result: LocalizationResult) {
    Log.d(TAG, "Localization success - mapCode: ${result.mapCode}, " +
            "mapCodes: ${result.mapCodes}, " +
            "position: [${result.position.joinToString()}], " +
            "rotation: [${result.rotation.joinToString()}], " +
            "confidence: ${result.confidence}")
}

onLocalizationFailure(error: String)

Called when localization fails. In MainActivity, this is handled by the AR activity.

Parameter	Type	Description
error	String	Error message describing the failure reason

onLocalizationFalsePositive(info: FalsePositiveInfo)

Called when a localization response was discarded because it contradicted the device's own AR trajectory. The request succeeded; the answer was wrong. The scene is left untouched.

Parameter	Type	Description
info	FalsePositiveInfo	Jump distance, threshold, consecutive count, map codes, confidence and reason

override fun onLocalizationFalsePositive(info: FalsePositiveInfo) {
    Log.w(TAG, "Discarded false positive: ${info.summary}")
}

This callback has a default no-op implementation, so it is optional to override.

onTrackingStateChanged(state: TrackingState)

Called when AR tracking state changes. Handled internally by the AR activities.

Parameter	Type	Description
state	TrackingState	Current tracking state (TRACKING, PAUSED, STOPPED)

onObjectTrackingSuccess(result: ObjectTrackingResult)

Called when an object is successfully tracked. Forwarded from ObjectTrackingActivity via MultiSetSDK.getCallback().

Parameter	Type	Description
result	ObjectTrackingResult	Contains object code, pose data, and confidence

override fun onObjectTrackingSuccess(result: ObjectTrackingResult) {
    Log.d(TAG, "Object tracking success - objectCode: ${result.objectCode}, " +
            "position: [${result.position.joinToString()}], " +
            "confidence: ${result.confidence}")
}

onObjectTrackingFailure(error: String)

Called when object tracking fails.

Parameter	Type	Description
error	String	Error message describing the failure reason

override fun onObjectTrackingFailure(error: String) {
    Log.d(TAG, "Object tracking failure: $error")
}

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LocalizationResult

Property	Type	Description
mapCode	String	The code of the map where localization succeeded
mapCodes	List<String>	All map codes returned by the localization API
position	FloatArray	XYZ position coordinates
rotation	FloatArray	XYZW quaternion rotation
confidence	Float?	Confidence score of the localization (0.0 - 1.0)
geoCoordinates	GeoCoordinates?	Optional geographic coordinates

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TrackingState

Value	Description
TRACKING	AR tracking is working normally
PAUSED	AR tracking is temporarily paused
STOPPED	AR tracking has stopped

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Usage Example

class MainActivity : AppCompatActivity(), MultiSetSDKCallback {

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)

        // Initialize SDK
        val config = MultiSetSDKConfig.Builder(
            BuildConfig.MULTISET_CLIENT_ID,
            BuildConfig.MULTISET_CLIENT_SECRET
        )
        .mapCode(BuildConfig.MULTISET_MAP_CODE)
        .enableMeshVisualization(true)
        .backgroundLocalization(true)
        .build()

        MultiSetSDK.initialize(this, config, this)
    }

    override fun onAuthenticationSuccess() {
        // Enable localization and object tracking buttons in the UI
    }

    // Launch localization
    fun launchLocalization(mode: LocalizationMode) {
        val intent = Intent(this, MultiSetLocalizationActivity::class.java)
        intent.putExtra(MultiSetLocalizationActivity.EXTRA_LOCALIZATION_MODE, mode.name)
        startActivity(intent)
    }

    // Launch object tracking
    fun launchObjectTracking() {
        val objectCodes = BuildConfig.MULTISET_OBJECT_CODES
            .split(",").map { it.trim() }.filter { it.isNotEmpty() }.toTypedArray()

        ObjectTrackingConfig.objectCodes = objectCodes
        ObjectTrackingConfig.validate()

        val intent = Intent(this, ObjectTrackingActivity::class.java)
        intent.putExtra(ObjectTrackingActivity.EXTRA_OBJECT_CODES, objectCodes)
        startActivity(intent)
    }

    override fun onLocalizationSuccess(result: LocalizationResult) {
        Log.d("MainActivity", "Localized at mapCode: ${result.mapCode}")
    }

    override fun onObjectTrackingSuccess(result: ObjectTrackingResult) {
        Log.d("MainActivity", "Tracked object: ${result.objectCode}")
    }

    override fun onObjectTrackingFailure(error: String) {
        Log.e("MainActivity", "Tracking failed: $error")
    }

    override fun onAuthenticationFailure(error: String) {
        Toast.makeText(this, "Auth failed: $error", Toast.LENGTH_SHORT).show()
    }

    // ... other callback implementations
}

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Related

• MultiSetLocalizationActivity

• ObjectTrackingActivity

• LocalizationConfig

• ObjectTrackingConfig