Initializing PnP Android SDK

After installation, the next step to use Web3Auth is to configure & initialize the SDK.

However, configuring and initializing is a four-step process:

1. Creating a Web3Auth Instance
2. Setting a Result URL
3. Triggering Login exceptions
4. Initialize Web3Auth

Create Web3Auth Instance

The first step is to create the Web3Auth instance, and configure the Whitelabeling, Session time, and Custom Authentication. Please note that these are the most critical steps where you need to pass on different parameters according to the preference of your project.

Parameters

The Web3Auth Constructor takes an object with Web3AuthOptions as input.

Table

Parameter	Description
context	Android context to launch Web-based authentication, usually is the current activity. It's a mandatory field, and accepts android.content.Context as a value.
clientId	Your Web3Auth Client ID. You can get it from Web3Auth Dashboard under project details. It's a mandatory field of type String
network	Defines the Web3Auth network. It's a mandatory field of type Network.
redirectUrl	URL that Web3Auth will redirect API responses upon successful authentication from browser. It's a mandatory field of type Uri.
whiteLabel?	WhiteLabel options for web3auth. It helps you define custom UI, branding, and translations for your brand app. It takes WhiteLabelData as a value.
loginConfig?	Login config for the custom verifiers. It takes HashMap<String, LoginConfigItem> as a value.
useCoreKitKey?	Use CoreKit Key to get core kit key. It's an optional field with default value as false.
chainNamespace?	Chain Namespace [EIP155 and SOLANA]. It takes ChainNamespace as a value.
mfaSettings?	Allows developers to configure the Mfa settings for authentication. It takes MfaSettings as a value.
sessionTime?	It allows developers to configure the session management time. Session Time is in seconds, default is 86400 seconds which is 1 day. sessionTime can be max 7 days

Interface

data class Web3AuthOptions(
    var context: Context,
    val clientId: String,
    val network: Network,
    var buildEnv: BuildEnv? = BuildEnv.PRODUCTION,
    @Transient var redirectUrl: Uri,
    var sdkUrl: String = getSdkUrl(buildEnv),
    val whiteLabel: WhiteLabelData? = null,
    val loginConfig: HashMap<String, LoginConfigItem>? = null,
    val useCoreKitKey: Boolean? = false,
    val chainNamespace: ChainNamespace? = ChainNamespace.EIP155,
    val mfaSettings: MfaSettings? = null,
    val sessionTime: Int? = 86400
)

Instantiate Web3Auth

import com.web3auth.core.Web3Auth
import com.web3auth.core.types.Web3AuthOptions

var web3Auth = Web3Auth(
  Web3AuthOptions(
    context = this,
    clientId = "YOUR_WEB3AUTH_CLIENT_ID", // Pass over your Web3Auth Client ID from Developer Dashboard
    network = Network.MAINNET,
    redirectUrl = Uri.parse("{YOUR_APP_PACKAGE_NAME}://auth"),
  )
)

// Handle user signing in when app is in background
web3Auth.setResultUrl(intent?.data)

Set Result URL

Whenever user initiates a login flow, a new intent of CustomTabs is launched. It’s necessary step to use setResultUrl in onNewIntent method to successful track the login process.

override fun onNewIntent(intent: Intent?) {
  super.onNewIntent(intent)

  // Handle user signing in when app is active
  web3Auth.setResultUrl(intent.data)
}

Triggering Login exceptions

The setCustomTabsClosed method can be used to trigger login exceptions for Android. The Android SDK uses the custom tabs and from current implementation of chrome custom tab, it's not possible to add a listener directly to chrome custom tab close button and trigger login exceptions.

Hence, it's necessary to use setCustomTabsClosed method in your login screen to trigger exceptions.

class MainActivity : AppCompatActivity() {
    // Additional code

    override fun onResume() {
        super.onResume()
        if (Web3Auth.getCustomTabsClosed()) {
            Toast.makeText(this, "User closed the browser.", Toast.LENGTH_SHORT).show()
            web3Auth.setResultUrl(null)
            Web3Auth.setCustomTabsClosed(false)
        }
    }

    // Additional code
}

Initialize Web3Auth

After instantiating Web3Auth, the next step is to initialize it using the initialize method. This method is essential for setting up the SDK, checking for any active sessions, and fetching the whitelabel configuration from your dashboard.

Once the initialize method executes successfully, you can use the getPrivKey or getEd25519PrivKey methods to verify if an active session exists. If there is no active session, these methods will return an empty string; otherwise, they will return the respective private key.

Note that if the API call to fetch the project configuration fails, the method will throw an error.

val sessionResponse: CompletableFuture<Void> = web3Auth.initialize()
sessionResponse.whenComplete { _, error ->
  if (error == null) {
    // Check for the active session
    if(web3Auth.getPrivKey()isNotEmpty()) {
      // Active session found
    }
    // No active session is not present

  } else {
    // Handle the error
  }
}