Skip to content
Voice-video/Getting started/
/
Make a call
Last updated

Make an audio call

This guide shows you how to make an audio call in your Android app. We assume you have already set up your Android app with the In‑app Calling SDK.

If you haven't already, first create an app. Or, if you prefer, continue to handle incoming calls.

Set up the UI

Before you can make a call, you need to set up the app's UI.

The UI for placing a call is handled inside a dedicated activity: PlaceCallActivity (earlier references to LoggedInActivity in some samples serve broader post‑login functionality). Define this activity inside your AndroidManifest.xml file.

app/src/main/AndroidManifest.xml

<activity android:name=".PlaceCallActivity" />

Initiate an audio call

  1. Similarly to LoginActivity, create a basic layout containing an input field for the callee username and a button that initiates the call.

app/src/main/res/layout/main.xml

<!-- PlaceCallActivity layout excerpt -->
<com.google.android.material.textfield.TextInputLayout
    style="@style/Widget.MaterialComponents.TextInputLayout.OutlinedBox.Dense"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:layout_marginTop="@dimen/margin_big"
    android:layout_marginBottom="@dimen/input_layout_bottom"
    android:hint="@string/enter_callee_id"
    app:counterMaxLength="50"
    app:endIconCheckable="true"
    app:startIconDrawable="@android:drawable/presence_audio_online"
    app:startIconTint="@color/colorPrimaryDark">

    <com.google.android.material.textfield.TextInputEditText
        android:id="@+id/callName"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:inputType="text"
        android:imeOptions="actionDone" />

</com.google.android.material.textfield.TextInputLayout>

<com.google.android.material.button.MaterialButton
    android:id="@+id/callButton"
    style="@style/Widget.MaterialComponents.Button.Icon"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:layout_marginStart="@dimen/margin_average"
    android:layout_marginTop="@dimen/margin_small"
    android:layout_marginEnd="@dimen/margin_average"
    android:padding="@dimen/margin_base_plus"
    android:text="@string/call"
    android:textAlignment="center"
    android:textColor="@color/white"
    app:backgroundTint="@color/sinch_green"
    app:icon="@drawable/ic_outline_phone_in_talk_24"
    app:iconGravity="textEnd" />
  1. Inside SinchService's binder implementation, add a method that uses the call controller to initiate the call:

app/src/main/java/com/sinch/rtc/sample/push/SinchService.kt

fun callUser(userId: String): Call {
    val sinchClient = sinchClient ?: throw IllegalStateException("Sinch client is not created")
    return sinchClient.callController.callUser(userId, MediaConstraints(false))
}
  1. Bind the call button to the method and assign a CallListener to be notified about changes in the call state:

app/src/main/java/com/sinch/rtc/sample/push/PlaceCallActivity.kt

override fun onCreate(savedInstanceState: Bundle?) {
    super.onCreate(savedInstanceState)
    // ...
    callButton.apply {
        isEnabled = false
        setOnClickListener { callButtonClicked() }
    }
}

private fun callButtonClicked() {
    val userName = calleeNameEditText.text.toString()
    // Validate input (non-empty) before calling if needed
    val call = sinchServiceInterface?.callUser(userName)
    // Launch in-call UI
    startActivity(callScreen)
}

Manage required permissions

If you try to initiate an audio call now, the application will crash with the following error output:

Process: com.sinch.rtc.demovvsdk, PID: 876
com.sinch.android.rtc.MissingPermissionException: Requires permission: android.permission.RECORD_AUDIO

Although Internet permissions were declared earlier, RECORD_AUDIO is a runtime permission and must be requested during the user's interaction with the app.

  1. Modify the Android Manifest file by declaring usage of the RECORD_AUDIO permission.

app/src/main/AndroidManifest.xml

<uses-permission android:name="android.permission.RECORD_AUDIO" />
  1. Before the user logs in, request the permission explicitly and start the client only if it was granted.

app/src/main/java/com/sinch/rtc/sample/push/BaseActivity.kt

private val messenger = Messenger(object : Handler() {
    override fun handleMessage(msg: Message) {
        when (msg.what) {
            SinchService.MESSAGE_PERMISSIONS_NEEDED -> {
                val requiredPermission = msg.data.getString(SinchService.REQUIRED_PERMISSION)
                ActivityCompat.requestPermissions(
                    this@BaseActivity,
                    arrayOf(
                        requiredPermission,
                        Manifest.permission.POST_NOTIFICATIONS
                    ),
                    0
                )
            }
            else -> { /* ignore */ }
        }
    }
})

override fun onRequestPermissionsResult(
    requestCode: Int,
    permissions: Array<String>,
    grantResults: IntArray
) {
    super.onRequestPermissionsResult(requestCode, permissions, grantResults)
    // ... evaluate grantResults
    sinchServiceInterface?.retryStartAfterPermissionGranted()
}
Note

An in‑depth overview of runtime permissions, grant results, and handling workflow can be found in the official Android documentation: Permissions overview.

Next steps

Now that you've made a call, you can set up your application to handle incoming calls.

Handle incoming calls

Previous page
Next page