How to build WeChat (Native) sign-in with Android (Kotlin / Java)

For our new friends:

Logto is an Auth0 alternative designed for modern apps and SaaS products. It offers both Cloud and Open-source services to help you quickly launch your identity and management (IAM) system. Enjoy authentication, authorization, and multi-tenant management all in one.

We recommend starting with a free development tenant on Logto Cloud. This allows you to explore all the features easily.

In this article, we will go through the steps to quickly build the WeChat (Native) sign-in experience (user authentication) with Android (Kotlin / Java) and Logto.

Prerequisites

A running Logto instance. Check out the introduction page to get started.
Basic knowledge of Android (Kotlin / Java).
A usable WeChat (Native) account.

Create an application in Logto

Logto is based on OpenID Connect (OIDC) authentication and OAuth 2.0 authorization. It supports federated identity management across multiple applications, commonly called Single Sign-On (SSO).

To create your Native app application, simply follow these steps:

Open the Logto Console. In the "Get started" section, click the "View all" link to open the application frameworks list. Alternatively, you can navigate to Logto Console > Applications, and click the "Create application" button.
In the opening modal, click the "Native app" section or filter all the available "Native app" frameworks using the quick filter checkboxes on the left. Click the "Android" framework card to start creating your application.
Enter the application name, e.g., "Bookstore," and click "Create application".

🎉 Ta-da! You just created your first application in Logto. You'll see a congrats page which includes a detailed integration guide. Follow the guide to see what the experience will be in your application.

Integrate Android with Logto

tip:

The example is based on View system and View Model, but the concepts are the same when using Jetpack Compose.
The example is written in Kotlin, but the concepts are the same for Java.
Both Kotlin and Java sample projects are available on our SDK repository.
The tutorial video is available on our YouTube channel.

Installation

note:

The minimum supported Android API level of Logto Android SDK is level 24.

Before you install Logto Android SDK, ensure mavenCentral() is added to your repository configuration in the Gradle project build file:

settings.gradle.kts
dependencyResolutionManagement {
  repositories {
    mavenCentral()
  }
}

Add Logto Android SDK to your dependencies:

Kotlin
Groovy

build.gradle.kts
dependencies {
  implementation("io.logto.sdk:android:1.1.3")
}

build.gradle
dependencies {
  implementation 'io.logto.sdk:android:1.1.3'
}

Since the SDK needs internet access, you need to add the following permission to your AndroidManifest.xml file:

AndroidManifest.xml
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
  xmlns:tools="http://schemas.android.com/tools">

  <!-- add internet permission -->
  <uses-permission android:name="android.permission.INTERNET" />

  <!-- other configurations... -->
</manifest>

Init LogtoClient

Create a LogtoViewModel.kt and init LogtoClient in this view model:

LogtoViewModel.kt
//...with other imports
import io.logto.sdk.android.LogtoClient
import io.logto.sdk.android.type.LogtoConfig

class LogtoViewModel(application: Application) : AndroidViewModel(application) {
    private val logtoConfig = LogtoConfig(
          endpoint = "<your-logto-endpoint>",
          appId = "<your-app-id>",
          scopes = null,
          resources = null,
          usingPersistStorage = true,
    )

    private val logtoClient = LogtoClient(logtoConfig, application)

    companion object {
        val Factory: ViewModelProvider.Factory = object : ViewModelProvider.Factory {
            @Suppress("UNCHECKED_CAST")
            override fun <T : ViewModel> create(
                modelClass: Class<T>,
                extras: CreationExtras
            ): T {
                // Get the Application object from extras
                val application = checkNotNull(extras[APPLICATION_KEY])
                return LogtoViewModel(application) as T
            }
        }
    }
}

then, create a LogtoViewModel for your MainActivity.kt:

MainActivity.kt
//...with other imports
class MainActivity : AppCompatActivity() {
    private val logtoViewModel: LogtoViewModel by viewModels { LogtoViewModel.Factory }
    //...other codes
}

Configure redirect URI

Let's switch to the Application details page of Logto Console. Add a Redirect URI io.logto.android://io.logto.sample/callback and click "Save changes".

note:

Before calling logtoClient.signIn, make sure you have correctly configured Redirect URI in Admin Console.

You can use logtoClient.signIn to sign in the user and logtoClient.signOut to sign out the user.

For example, in an Android app:

LogtoModelView.kt
//...with other imports
class LogtoViewModel(application: Application) : AndroidViewModel(application) {
    // ...other codes

    // Add a live data to observe the authentication status
    private val _authenticated = MutableLiveData(logtoClient.isAuthenticated)
    val authenticated: LiveData<Boolean>
        get() = _authenticated

    fun signIn(context: Activity) {
        logtoClient.signIn(context, "io.logto.android://io.logto.sample/callback") { logtoException ->
            logtoException?.let { println(it) }
            // Update the live data
            _authenticated.postValue(logtoClient.isAuthenticated)
        }
    }

    fun signOut() {
        logtoClient.signOut { logtoException ->
            logtoException?.let { println(it) }
            // Update the live data
            _authenticated.postValue(logtoClient.isAuthenticated)
        }
    }
}

Then call the signIn and signOut methods in your activity:

MainActivity.kt
class MainActivity : AppCompatActivity() {
    override fun onCreate(savedInstanceState: Bundle?) {
        //...other codes

        // Assume you have a button with id "sign_in_button" in your layout
        val signInButton = findViewById<Button>(R.id.sign_in_button)
        signInButton.setOnClickListener {
            logtoViewModel.signIn(this)
        }

        // Assume you have a button with id "sign_out_button" in your layout
        val signOutButton = findViewById<Button>(R.id.sign_out_button)
        signOutButton.setOnClickListener {
            if (logtoViewModel.authenticated) { // Check if the user is authenticated
                logtoViewModel.signOut()
            }
        }

        // Observe the authentication status to update the UI
        logtoViewModel.authenticated.observe(this) { authenticated ->
            if (authenticated) {
                // The user is authenticated
                signInButton.visibility = View.GONE
                signOutButton.visibility = View.VISIBLE
            } else {
                // The user is not authenticated
                signInButton.visibility = View.VISIBLE
                signOutButton.visibility = View.GONE
            }
        }

    }
}

Checkpoint: Test your application

Now, you can test your application:

Run your application, you will see the sign-in button.
Click the sign-in button, the SDK will init the sign-in process and redirect you to the Logto sign-in page.
After you signed in, you will be redirected back to your application and see the sign-out button.
Click the sign-out button to clear token storage and sign out.

Add WeChat (Native) connector

To enable quick sign-in and improve user conversion, connect with Android as an identity provider. The Logto social connector helps you establish this connection in minutes by allowing several parameter inputs.

To add a social connector, simply follow these steps:

Navigate to Console > Connectors > Social Connectors.
Click "Add social connector" and select "WeChat (Native)".
Follow the README guide and complete required fields and customize settings.

note:

If you are following the in-place Connector guide, you can skip the next section.

Set up WeChat mobile app

Create a mobile app in the WeChat Open Platform

tip:

You can skip some sections if you have already finished.

Create an account

Open https://open.weixin.qq.com/, click the "Sign Up" button in the upper-right corner, then finish the sign-up process.

Create a mobile app

Sign in with the account you just created. In the "Mobile Application" (移动应用) tab, click the big green button "Create a mobile app" (创建移动应用).

Let's fill out the required info in the application form.

Basic info

Most of them are pretty straightforward, and we have several tips here:

If you just want to test WeChat sign-in and the app is not on the App Store, in the "App is available" section, choose "No" to skip the "App download link".
The "App operation flow chart" looks tricky. From our experience, you need to prepare a simple flowchart and several app screenshots to improve the possibility of passing the review.

Click "Next step" to move on.

Platform info

You can configure one or both iOS and Android platforms to integrate Logto with WeChat native sign-in.

iOS app

Check "iOS app" (iOS 应用), then check the target device type of your app accordingly.

If you chose "No" for the App Store availability, you cloud skip filling out the "AppStore download address" here.

Fill out Bundle ID, Test version Bundle ID, and Universal Links (actually, only one link is needed 😂).

note:

Bundle ID and Test version Bundle ID can be the same value.

tip:

WeChat requires universal link for native sign-in. If you haven't set up or don't know it, please refer to the Apple official doc.

Android app

Check "Android app" (Android 应用).

Fill out Application Signing Signature (应用签名) and Application Package Name (应用包名).

note:

You need to sign your app to get a signature. Refer to the Sign your app for more info.

After finish signing, you can execute the signingReport task to get the signing signature.

./gradlew your-android-project:signingReport

The MD5 value of the corresponding build variant's report will be the Application Signing Signature (应用签名), but remember to remove all semicolons from the value and lowercase it.

E.g. 1A:2B:3C:4D -> 1a2b3c4d.

Waiting for the review result

After completing the platform info, click "Submit Review" to continue. Usually, the review goes fast, which will end within 1-2 days.

We suspect the reviewer is allocated randomly on each submission since the standard is floating. You may get rejected the first time, but don't give up! State your status quo and ask the reviewer how to modify it.

iOS

We assume you have integrated Logto iOS SDK in your app. In this case, things are pretty simple, and you don't even need to read the WeChat SDK doc:

1. Configure universal link and URL scheme in your Xcode project

In the Xcode project -> Signing & Capabilities tab, add the "Associated Domains" capability and the universal link you configured before.

Then goes to the "Info" tab, add a custom URL scheme with the WeChat App ID.

Finally open your Info.plist, add weixinULAPI and weixin under LSApplicationQueriesSchemes.

note:

We know these actions are not very reasonable, but this is the minimum workable solution we found. See the magical official guide for more info.

2. Add LogtoSocialPluginWechat to your Xcode project

Add the framework:

And add -ObjC to your Build Settings > Linking > Other Linker Flags:

note:

The plugin includes WeChat Open SDK 1.9.2. You can directly use import WechatOpenSDK once imported the plugin.

3. Add the plugin to your LogtoClient init options

let logtoClient = LogtoClient(
  useConfig: config,
  socialPlugins: [LogtoSocialPluginWechat()]
)

4. Handle onOpenURL properly

note:

The function LogtoClient.handle(url:) will handle all the native connectors you enabled. You only need to call it once.

// SwiftUI
YourRootView()
  .onOpenURL { url in
      LogtoClient.handle(url: url)
  }

// or AppDelegate
func application(_ app: UIApplication, open url: URL, options: /*...*/) -> Bool {
  LogtoClient.handle(url: url)
}

Android

We assume you have integrated Logto Android SDK in your app. In this case, things are pretty simple, and you don't even need to read the WeChat SDK doc:

1. Add Wechat Open SDK to your project

Ensure the mavenCentral() repository is in your Gradle project repositories:

repositories {
  // ...
  mavenCentral()
}

Add the Wechat Open SDK to your dependencies:

dependencies {
  // ...
  api("com.tencent.mm.opensdk:wechat-sdk-android:6.8.0")  // kotlin-script
  // or
  api 'com.tencent.mm.opensdk:wechat-sdk-android:6.8.0'   // groovy-script
}

2. Introduce WXEntryActivity to your project

Create a wxapi package under your package root and add the WXEntryActivity in the wxapi package (Take com.sample.app as an example):

// WXEntryActivity.kt
package com.sample.app.wxapi

import io.logto.sdk.android.auth.social.wechat.WechatSocialResultActivity

class WXEntryActivity: WechatSocialResultActivity()

// WXEntryActivity.java
package com.sample.app.wxapi

import io.logto.sdk.android.auth.social.wechat.WechatSocialResultActivity

public class WXEntryActivity extends WechatSocialResultActivity {}

The final position of the WXEntryActivity under the project should look like this (Take Kotlin as an example):

src/main/kotlin/com/sample/app/wxapi/WXEntryActivity.kt

3. Modify the AndroidManifest.xml

Add the following line to your AndroidManifest.xml:

\<?xml version="1.0" encoding="utf-8"?>
\<manifest xmlns:android="http://schemas.android.com/apk/res/android"
  package="com.sample.app">

  \<application>
    \<!-- line to be added -->
    \<activity android:name=".wxapi.WXEntryActivity" android:exported="true"/>
  \</application>

\</manifest>

Save your configuration

Double check you have filled out necessary values in the Logto connector configuration area. Click "Save and Done" (or "Save changes") and the WeChat (Native) connector should be available now.

Once you create a social connector successfully, you can enable it as a "Continue with WeChat (Native)" button in Sign-in Experience.

Navigate to Console > Sign-in experience > Sign-up and sign-in.
(Optional) Choose "Not applicable" for sign-up identifier if you need social login only.
Add configured WeChat (Native) connector to the "Social sign-in" section.

Testing and Validation

Return to your Android (Kotlin / Java) app. You should now be able to sign in with WeChat (Native). Enjoy!

Create an application in Logto​

Integrate Android with Logto​

Installation​

Init LogtoClient​

Configure redirect URI​

Implement sign-in and sign-out​

Checkpoint: Test your application​

Add WeChat (Native) connector​

Set up WeChat mobile app​

Create a mobile app in the WeChat Open Platform​

Create an account​

Create a mobile app​

Basic info​

Platform info​

Waiting for the review result​

Enable WeChat native sign-in in your app​

iOS​

Android​

Save your configuration​

Enable WeChat (Native) connector in Sign-in Experience​

Testing and Validation​

Further readings​

Create an application in Logto

Integrate Android with Logto

Installation

Init LogtoClient

Configure redirect URI

Implement sign-in and sign-out

Checkpoint: Test your application

Add WeChat (Native) connector

Set up WeChat mobile app

Create a mobile app in the WeChat Open Platform

Create an account

Create a mobile app

Basic info

Platform info

Waiting for the review result

Enable WeChat native sign-in in your app

iOS

Android

Save your configuration

Enable WeChat (Native) connector in Sign-in Experience

Testing and Validation

Further readings