android-phone-number-hint.md

📱 Phone Number Hint API Implementation Guide

Follow the official documentation here: Phone Number Hint API

The Phone Number Hint API provides a seamless way to retrieve a user’s SIM-based phone numbers without requiring additional permissions or manual input.

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🚀 Implementation Steps

1. Add Dependency

Include the following in your app/build.gradle file:

// For Phone Number Hint API
implementation 'com.google.android.gms:play-services-auth:21.3.0'

// For Parsing and Formatting Phone Numbers (optional)
implementation("com.googlecode.libphonenumber:libphonenumber:8.13.24") 

---

2. Create a GetPhoneNumberHintIntentRequest Object

Set up the phone number hint request:

val request = GetPhoneNumberHintIntentRequest.builder().build()

val signInClient = Identity.getSignInClient(this)
signInClient.getPhoneNumberHintIntent(request)
    .addOnSuccessListener { result: PendingIntent ->
        try {
            // Launch the hint picker to display phone numbers
            phoneNumberHintIntentResultLauncher.launch(
                IntentSenderRequest.Builder(result).build()
            )
        } catch (e: Exception) {
            Log.e("PhoneNumberHint", "Launching the PendingIntent failed", e)
        }
    }
    .addOnFailureListener { e ->
        Log.e("PhoneNumberHint", "Phone Number Hint failed", e)
    }

---

3. Handle the Result

Register an ActivityResultLauncher to process the result:

private val phoneNumberHintIntentResultLauncher =
    registerForActivityResult(ActivityResultContracts.StartIntentSenderForResult()) { result ->
        if (result.resultCode == Activity.RESULT_OK && result.data != null) {
            try {
                // Extract the phone number from the intent result
                val phoneNumber = Identity.getSignInClient(requireActivity())
                    .getPhoneNumberFromIntent(result.data)
                
                val phone = detectCountryAndExtractNationalNumber(phoneNumber)
                binding.phoneCodeEditText.setText(phone.second)

                Log.d("PhoneHint", "Phone number: $phoneNumber")
            } catch (e: Exception) {
                Log.e("PhoneHint", "Failed to retrieve phone number: ${e.message}")
                Toast.makeText(requireContext(), "Failed to retrieve phone number", Toast.LENGTH_SHORT).show()
            }
        } else {
            Log.e("PhoneHint", "Phone number hint was cancelled or failed")
            Toast.makeText(requireContext(), "Phone number hint cancelled", Toast.LENGTH_SHORT).show()
        }
    }

---

🛡️ Key Notes

• The API works without requiring READ_PHONE_STATE permission.
• Ensure you handle possible exceptions gracefully.
• Test on a physical device with an active SIM card.

For more details, refer to the official documentation. 🚀

✅ Complete example:

import android.app.PendingIntent
import android.content.IntentSender
import android.util.Log
import android.widget.Toast
import androidx.activity.result.ActivityResultLauncher
import androidx.activity.result.IntentSenderRequest
import androidx.activity.result.contract.ActivityResultContracts
import androidx.fragment.app.Fragment
import com.google.android.gms.auth.api.identity.GetPhoneNumberHintIntentRequest
import com.google.android.gms.auth.api.identity.Identity

class PhoneNumberHintFragment : Fragment() {

    private lateinit var phoneNumberHintIntentResultLauncher: ActivityResultLauncher<IntentSenderRequest>

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

        // Initialize ActivityResultLauncher once
        phoneNumberHintIntentResultLauncher =
            registerForActivityResult(ActivityResultContracts.StartIntentSenderForResult()) { result ->
                if (result.resultCode == Activity.RESULT_OK && result.data != null) {
                    try {
                        val phoneNumber = Identity.getSignInClient(requireActivity())
                            .getPhoneNumberFromIntent(result.data)
                        
                        val phone = detectCountryAndExtractNationalNumber(phoneNumber)
                        binding.phoneCodeEditText.setText(phone.second)

                        Log.d("PhoneHint", "Phone number: $phoneNumber")
                    } catch (e: Exception) {
                        Log.e("PhoneHint", "Failed to retrieve phone number: ${e.message}")
                        Toast.makeText(requireContext(), "Failed to retrieve phone number", Toast.LENGTH_SHORT).show()
                    }
                } else {
                    Log.e("PhoneHint", "Phone number hint was cancelled or failed")
                    Toast.makeText(requireContext(), "Phone number hint cancelled", Toast.LENGTH_SHORT).show()
                }
            }
    }

    fun showPhoneNumberHint() {
        try {
            val request: GetPhoneNumberHintIntentRequest = GetPhoneNumberHintIntentRequest.builder().build()

            Identity.getSignInClient(requireActivity())
                .getPhoneNumberHintIntent(request)
                .addOnSuccessListener { result: PendingIntent ->
                    try {
                        phoneNumberHintIntentResultLauncher.launch(
                            IntentSenderRequest.Builder(result).build()
                        )
                    } catch (e: IntentSender.SendIntentException) {
                        Log.e("PhoneHint", "Launching the PendingIntent failed: ${e.message}")
                        Toast.makeText(requireContext(), "Failed to launch phone number hint", Toast.LENGTH_SHORT).show()
                    }
                }
                .addOnFailureListener { e ->
                    Log.e("PhoneHint", "Phone Number Hint failed: ${e.message}")
                    Toast.makeText(requireContext(), "Failed to retrieve phone number hint", Toast.LENGTH_LONG).show()
                }
        } catch (e: Exception) {
            Log.e("PhoneHint", "Unexpected error: ${e.message}")
            Toast.makeText(requireContext(), "An unexpected error occurred", Toast.LENGTH_LONG).show()
        }
    }

    fun detectCountryAndExtractNationalNumber(phoneNumber: String): Pair<String?, String?> {
        val phoneUtil = PhoneNumberUtil.getInstance()
        return try {
            // Parse the phone number without specifying a region
            val parsedNumber: Phonenumber.PhoneNumber = phoneUtil.parse(phoneNumber, null)
    
            // Extract region and national number
            val countryCode = phoneUtil.getRegionCodeForNumber(parsedNumber)
            val nationalNumber = parsedNumber.nationalNumber.toString()
    
            Log.d("PhoneHint", "Detected country: $countryCode, National number: $nationalNumber")
    
            Pair(countryCode, nationalNumber)
        } catch (e: NumberParseException) {
            Log.e("PhoneHint", "Failed to parse phone number: ${e.message}")
            Pair(null, null)
        }
    }
}