CallRedirectionService Implementation not working

Question

Android Q has introduced CallRedirectionService API - seems like one of the way 3rd party apps can use it is to cancel calls and reroute them over VoIP - essentially intercepting the phone calls.

I was trying to implement this class as below

public class CallMonitorService extends CallRedirectionService {
    private static final String TAG = "CallMonitorService";

    public CallMonitorService() {
    }

    @Override
    public void onPlaceCall(Uri uri, PhoneAccountHandle phoneAccountHandle, boolean b) {
        Log.e(TAG, "onPlaceCall:### ");
    }


}

As you can see I am overriding onPlaceCall which is abstract method in the CallRedirectionService and simply keeping a log statement to check/test if this callback method hook is invoked by Android framework.

I added this service in my Manifest.xml as well as below, which is what is documented in the Source code of CallRedirectionService class

<service
                android:name=".CallMonitorService"
                android:permission="android.permission.BIND_REDIRECTION_SERVICE"
                android:enabled="true"
                android:exported="true">
            <intent-filter>
                <action android:name="android.telecom.CallRedirectionService"/>
            </intent-filter>
        </service>

My Guess is that when Android system places a outgoing call this onPlaceCall will be invoked and then we can write our custom code to do further action on the outgoing call. Am not 100% sure if this is how CallRedirectionService is supposed to work - By the way there is no example available in developer.android.com for how to implement CallRedirectionService as of this writing. I set both minSdkVersion 29 targetSdkVersion 29 in my build.gradle

However when the call is made - the onPlaceCall inside my Service is not getting invoked.

I am using Android Q Emulator for testing as i do not have Android phone running Android Q to test this - can this be not tested on Android emulator by placing a emulated phone call or What else Am I missing?

Answer 1

The problem is that at the moment documentation is not full and sample in documentation is not correct. To fix this, in your AndroidManifest it is needed to change

android:permission="android.permission.BIND_REDIRECTION_SERVICE"

to

android:permission="android.permission.BIND_CALL_REDIRECTION_SERVICE"

This permission is incorrectly written inside the google documentation for https://developer.android.com/reference/android/telecom/CallRedirectionService.html currently.

Also, it is required to ask user to allow your application play this role. In google documentation this part missing at the moment :

 RoleManager roleManager = null;
    if (android.os.Build.VERSION.SDK_INT >= android.os.Build.VERSION_CODES.Q) {
        roleManager = (RoleManager) getSystemService(Context.ROLE_SERVICE);

        Intent intent = roleManager.createRequestRoleIntent(RoleManager.ROLE_CALL_REDIRECTION);
        startActivityForResult(intent, 1);}

Answer 2

Got it working (looking here). The next code will block all outgoing calls (it's just a sample...) :

MainActivity.kt

class MainActivity : AppCompatActivity() {
    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.activity_main)
        if (!isRedirection())
            roleAcquire(RoleManager.ROLE_CALL_REDIRECTION)
    }

    private fun isRedirection(): Boolean {
        return isRoleHeldByApp(RoleManager.ROLE_CALL_REDIRECTION)
    }

    private fun isRoleHeldByApp(roleName: String): Boolean {
        val roleManager: RoleManager?
        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.Q) {
            roleManager = getSystemService(RoleManager::class.java)
            return roleManager.isRoleHeld(roleName)
        }
        return false
    }

    private fun roleAcquire(roleName: String) {
        val roleManager: RoleManager?
        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.Q) {
            if (roleAvailable(roleName)) {
                roleManager = getSystemService(RoleManager::class.java)
                val intent = roleManager.createRequestRoleIntent(roleName)
                startActivityForResult(intent, ROLE_ACQUIRE_REQUEST_CODE)
            } else {
                Toast.makeText(this, "Redirection call with role in not available", Toast.LENGTH_SHORT).show()
            }
        }
    }

    private fun roleAvailable(roleName: String): Boolean {
        val roleManager: RoleManager?
        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.Q) {
            roleManager = getSystemService(RoleManager::class.java)
            return roleManager.isRoleAvailable(roleName)
        }
        return false
    }

    companion object {
        private const val ROLE_ACQUIRE_REQUEST_CODE = 4378
    }
}

MyCallRedirectionService.kt

class MyCallRedirectionService : CallRedirectionService() {

    override fun onPlaceCall(handle: Uri, initialPhoneAccount: PhoneAccountHandle, allowInteractiveResponse: Boolean) {
        Log.d("AppLog", "handle:$handle , initialPhoneAccount:$initialPhoneAccount , allowInteractiveResponse:$allowInteractiveResponse")
        cancelCall()
    }
}

AndroidManifest.xml

<manifest xmlns:android="http://schemas.android.com/apk/res/android" package="com.example.callredirectionservicesample">

    <application
        android:allowBackup="true" android:icon="@mipmap/ic_launcher" android:label="@string/app_name"
        android:roundIcon="@mipmap/ic_launcher_round" android:supportsRtl="true" android:theme="@style/AppTheme">
        <activity android:name=".MainActivity">
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />

                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>

        <service
            android:name=".MyCallRedirectionService"
            android:permission="android.permission.BIND_CALL_REDIRECTION_SERVICE">
            <intent-filter>
                <action android:name="android.telecom.CallRedirectionService" />
            </intent-filter>
        </service>
    </application>

</manifest>