Added a callback to get elapsed recording time in seconds.

.gitignore

@@ -26,4 +26,5 @@ captures/
 *.jks
 *.keystore
 .externalNativeBuild
-google-services.json
+google-services.json
+.idea/codeStyles/Project.xml

android-wave-recorder/src/main/java/com/github/squti/androidwaverecorder/WaveRecorder.kt

@@ -58,6 +58,11 @@ class WaveRecorder(private var filePath: String) {
      */
     var onStateChangeListener: ((RecorderState) -> Unit)? = null
 
+    /**
+     * Register a callback to get elapsed recording time in seconds
+     */
+    var onTimeElapsed: ((Long) -> Unit)? = null
+
     /**
      * Activates Noise Suppressor during recording if the device implements noise
      * suppression.
@@ -121,18 +126,22 @@ class WaveRecorder(private var filePath: String) {
             waveConfig.audioEncoding
         )
         val data = ByteArray(bufferSize)
-        val outputStream = File(filePath).outputStream()
+        val file = File(filePath)
+        val outputStream = file.outputStream()
         while (isRecording) {
             val operationStatus = audioRecorder.read(data, 0, bufferSize)
 
             if (AudioRecord.ERROR_INVALID_OPERATION != operationStatus) {
                 if (!isPaused) outputStream.write(data)
 
-                onAmplitudeListener?.let {
-
-                    withContext(Dispatchers.Default) {
+                withContext(Dispatchers.Main) {
+                    onAmplitudeListener?.let {
                         it(calculateAmplitudeMax(data))
                     }
+                    onTimeElapsed?.let {
+                        val audioLengthInSeconds: Long = file.length() / (2 * waveConfig.sampleRate)
+                        it(audioLengthInSeconds)
+                    }
                 }
 
 

build.gradle

@@ -1,14 +1,14 @@
 // Top-level build file where you can add configuration options common to all sub-projects/modules.
 
 buildscript {
-    ext.kotlin_version = '1.3.50'
+    ext.kotlin_version = '1.4.10'
     repositories {
         google()
         jcenter()
 
     }
     dependencies {
-        classpath 'com.android.tools.build:gradle:3.5.1'
+        classpath 'com.android.tools.build:gradle:4.0.1'
         classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:$kotlin_version"
         // NOTE: Do not place your application dependencies here; they belong
         // in the individual module build.gradle files

gradle/wrapper/gradle-wrapper.properties

@@ -3,4 +3,4 @@ distributionBase=GRADLE_USER_HOME
 distributionPath=wrapper/dists
 zipStoreBase=GRADLE_USER_HOME
 zipStorePath=wrapper/dists
-distributionUrl=https\://services.gradle.org/distributions/gradle-5.4.1-all.zip
+distributionUrl=https\://services.gradle.org/distributions/gradle-6.1.1-all.zip

sample/src/main/java/com/github/squti/androidwaverecordersample/MainActivity.kt

@@ -39,6 +39,8 @@ import kotlinx.android.synthetic.main.activity_main.*
 import kotlinx.coroutines.Dispatchers
 import kotlinx.coroutines.GlobalScope
 import kotlinx.coroutines.launch
+import java.util.*
+import java.util.concurrent.TimeUnit
 
 class MainActivity : AppCompatActivity() {
     private val PERMISSIONS_REQUEST_RECORD_AUDIO = 77
@@ -63,6 +65,11 @@ class MainActivity : AppCompatActivity() {
                 RecorderState.PAUSE -> pauseRecording()
             }
         }
+        waveRecorder.onTimeElapsed = {
+            Log.e(TAG, "onCreate: time elapsed $it")
+            timeTextView.text = formatTimeUnit(it * 1000)
+        }
+
         startStopRecordingButton.setOnClickListener {
 
             if (!isRecording) {
@@ -165,4 +172,19 @@ class MainActivity : AppCompatActivity() {
     companion object {
         private const val TAG = "MainActivity"
     }
+
+    private fun formatTimeUnit(timeInMilliseconds: Long): String {
+        return try {
+            String.format(
+                Locale.getDefault(),
+                "%02d:%02d",
+                TimeUnit.MILLISECONDS.toMinutes(timeInMilliseconds),
+                TimeUnit.MILLISECONDS.toSeconds(timeInMilliseconds) - TimeUnit.MINUTES.toSeconds(
+                    TimeUnit.MILLISECONDS.toMinutes(timeInMilliseconds)
+                )
+            )
+        } catch (e: Exception) {
+            "00:00"
+        }
+    }
 }

sample/src/main/res/layout/activity_main.xml

@@ -1,5 +1,4 @@
-<?xml version="1.0" encoding="utf-8"?>
-<!--
+<?xml version="1.0" encoding="utf-8"?><!--
   ~ MIT License
   ~
   ~ Copyright (c) 2019 squti
@@ -30,6 +29,17 @@
     android:layout_height="match_parent"
     tools:context=".MainActivity">
 
+    <TextView
+        android:id="@+id/timeTextView"
+        android:layout_width="wrap_content"
+        android:layout_height="wrap_content"
+        android:layout_marginBottom="10dp"
+        android:textSize="20sp"
+        app:layout_constraintBottom_toTopOf="@+id/startStopRecordingButton"
+        app:layout_constraintEnd_toEndOf="parent"
+        app:layout_constraintStart_toStartOf="parent"
+        tools:text="" />
+
 
     <Button
         android:id="@+id/startStopRecordingButton"