Quickstart KMP (Android)

Step 1 - Adding permissions to the Manifest

Add the following permissions in AndroidManifest.xml.

1<?xml version="1.0" encoding="utf-8"?>
2<manifest xmlns:android="http://schemas.android.com/apk/res/android">
3
4    <uses-permission android:name="android.permission.INTERNET" />
5    <uses-permission android:name="android.permission.ACCESS_WIFI_STATE" />
6    <uses-permission android:name="android.permission.FOREGROUND_SERVICE" />
7    <uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />
8    <uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION" />
9    <uses-permission android:name="android.permission.BLUETOOTH_ADMIN" />
10    <uses-permission android:name="android.permission.BLUETOOTH_SCAN" />
11    <uses-permission android:name="android.permission.BLUETOOTH_ADVERTISE" />
12    <uses-permission android:name="android.permission.BLUETOOTH_CONNECT" />
13    <uses-permission android:name="android.permission.POST_NOTIFICATIONS" />
14	
15	...
16
17</manifest>

Step 2 - Installing the Group Link library

In the settings.gradle.kts file, add the Jitpack URL inside the repositories section:

1...
2
3dependencyResolutionManagement {
4    repositories {
5        google {
6            ...
7        }
8        mavenCentral()
9        maven { url = uri("https://jitpack.io") } // Package repository for Android libraries.
10    }
11}
12
13...

In your project's build.gradle(androidApp), add the Group Link library by adding the following implementation:

1...
2
3dependencies {
4    ...
5    implementation("com.grouplinknetwork:lib-grouplinknetwork:4+") // Implementation of the Android library from the Group Link SDK
6}
7
8...

Step 3 - Creating the JSON file with your Group Link Token

Create a file named grouplink-services.json inside the directory .../androidApp/src/main/assets/.

Note: Create the directory .../androidApp/src/main/assets/ if it doesn't already exist in your project.

Estrutura de pastas de um app Android no Android Studio. O diretório androidApp/src/main/assets está expandido, com o arquivo grouplink-services.json selecionado e destacado.

Insert the following content below into the JSON

Note: Replace the YOUR_GROUP_LINK_TOKEN with your authentication token (provided by Group Link).

1{
2    "token": "YOUR_GROUP_LINK_TOKEN"
3}

Step 4 - Requesting permissions at runtime

In your project, search for your MainActivity and add the permissions following the model below.

Import the Group Link library.
Request permissions at runtime.

1// Example of permission request for Android
2
3package com.grouplink.kmp.test.androidApp
4
5import android.Manifest
6import android.app.Activity
7...
8import com.grouplinknetwork.GroupLink // <---- Importing the Group Link library
9
10
11class MainActivity : ComponentActivity() { 
12    private val REQUEST_PERMISSION_CODE = 420 // Request code for necessary permissions
13    private val ACTION_MANAGE_OVERLAY_PERMISSION_REQUEST_CODE = 0 // Request code for necessary permissions (Android 6)
14    private var count = 0 // Counter to prevent repeated permission requests
15    private var countAutoStart = 0 // Counter to prevent repeated auto-start permission requests
16
17	// Counter to prevent repeated auto-start permission requests
18    private val REQUIRED_PERMISSIONS = arrayOf(
19        Manifest.permission.BLUETOOTH,
20        Manifest.permission.BLUETOOTH_ADMIN,
21        Manifest.permission.ACCESS_FINE_LOCATION,
22        Manifest.permission.ACCESS_COARSE_LOCATION
23    )
24
25	// Permissions required for operation on Android 10 (Q)
26    private val REQUIRED_PERMISSIONS_Q = arrayOf(
27        Manifest.permission.BLUETOOTH,
28        Manifest.permission.BLUETOOTH_ADMIN,
29        Manifest.permission.ACCESS_FINE_LOCATION,
30        Manifest.permission.ACCESS_COARSE_LOCATION
31    )
32
33    // Logic for operation on Android 12 (S) and 13 (Tiramisu)
34    private fun getRequiredPermissionsS(): Array<String> {
35        return if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.TIRAMISU) {
36            arrayOf(
37                Manifest.permission.BLUETOOTH,
38                Manifest.permission.BLUETOOTH_ADMIN,
39                Manifest.permission.ACCESS_FINE_LOCATION,
40                Manifest.permission.ACCESS_COARSE_LOCATION,
41                Manifest.permission.BLUETOOTH_SCAN,
42                Manifest.permission.BLUETOOTH_ADVERTISE,
43                Manifest.permission.BLUETOOTH_CONNECT,
44                Manifest.permission.POST_NOTIFICATIONS
45            )
46        } else {
47            arrayOf(
48                Manifest.permission.BLUETOOTH,
49                Manifest.permission.BLUETOOTH_ADMIN,
50                Manifest.permission.ACCESS_FINE_LOCATION,
51                Manifest.permission.ACCESS_COARSE_LOCATION,
52                Manifest.permission.BLUETOOTH_SCAN,
53                Manifest.permission.BLUETOOTH_ADVERTISE,
54                Manifest.permission.BLUETOOTH_CONNECT
55            )
56        }
57    }
58
59	// The onCreate method is where the Group Link SDK is registered and permissions are requested
60    override fun onCreate(savedInstanceState: Bundle?) {
61        super.onCreate(savedInstanceState)
62        enableEdgeToEdge()
63
64		// Starting the Group Link SDK
65        GroupLink.register(
66            this, // Application context
67            false // Parameter to enable or disable debug mode
68        )
69
70        requestGlPermissions() // Requesting the necessary permissions for the Group Link SDK to function.
71
72        ...
73    }
74
75	// Method for requesting the necessary permissions
76    private fun requestGlPermissions() {
77        // Requesting permissions for Android 12 (S)
78        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.S) {
79            if (!hasNeededPermissionsS()) {
80                requestPermissionsS()
81                return
82            }
83        }
84
85        // Requesting permissions for Android 10 (Q)
86        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.Q && Build.VERSION.SDK_INT < Build.VERSION_CODES.S) {
87            if (!hasNeededPermissionsQ()) {
88                requestPermissionsQ()
89                return
90            }
91        }
92
93        // Requesting permissions up to Android 9 (Pie)
94        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M && Build.VERSION.SDK_INT < Build.VERSION_CODES.Q) {
95            if (!hasNeededPermissions()) {
96                requestPermissions()
97                return
98            }
99        }
100
101        // Checking if all permissions have already been granted
102        if (countAutoStart < 1) {
103            countAutoStart++
104        }
105    }
106
107	// Method to verify if the necessary permissions have been granted
108    private fun hasNeededPermissions(): Boolean {
109        return REQUIRED_PERMISSIONS.all {
110            ActivityCompat.checkSelfPermission(this, it) == PackageManager.PERMISSION_GRANTED
111        }
112    }
113
114	// Method to check if the necessary permissions have been granted for Android 10 (Q)
115    private fun hasNeededPermissionsQ(): Boolean {
116        return REQUIRED_PERMISSIONS_Q.all {
117            ActivityCompat.checkSelfPermission(this, it) == PackageManager.PERMISSION_GRANTED
118        }
119    }
120
121	// Method to check if the necessary permissions have been granted for Android 12 (S)
122    private fun hasNeededPermissionsS(): Boolean {
123        return if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.S) {
124            getRequiredPermissionsS().all {
125                ActivityCompat.checkSelfPermission(this, it) == PackageManager.PERMISSION_GRANTED
126            }
127        } else true
128    }
129
130	// Methods for requesting the necessary permissions for the Group Link SDK to function.
131    private fun requestPermissions() {
132        ActivityCompat.requestPermissions(this, REQUIRED_PERMISSIONS, REQUEST_PERMISSION_CODE)
133    }
134
135	// Method to request the necessary permissions for Android 10 (Q)
136    private fun requestPermissionsQ() {
137        ActivityCompat.requestPermissions(this, REQUIRED_PERMISSIONS_Q, REQUEST_PERMISSION_CODE)
138    }
139
140	// Method for requesting the necessary permissions for Android 12 (S)
141    private fun requestPermissionsS() {
142        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.S) {
143            ActivityCompat.requestPermissions(this, getRequiredPermissionsS(), REQUEST_PERMISSION_CODE)
144        }
145    }
146
147	// Method for handling the results of permission requests.
148    override fun onRequestPermissionsResult(requestCode: Int, permissions: Array<String>, grantResults: IntArray) {
149        if (requestCode == REQUEST_PERMISSION_CODE) {
150            if (count < REQUIRED_PERMISSIONS_Q.size) {
151                count++
152                requestGlPermissions()
153                return
154            }
155			
156            if (countAutoStart < 1) {
157                countAutoStart++
158            }
159        }
160		
161        super.onRequestPermissionsResult(requestCode, permissions, grantResults)
162    }
163}
164
165...
166

Now that the Group Link SDK for Android is implemented and the native features are configured, your KMP application is ready to interact with our ecosystem!