Develop Reference

How to play audio through earpiece in android 12?

I am developing a voice call app for android using PeerJS and WebView. And I want the audio to play through the earpiece. Here is my code,
private fun initAudio(){
am = getSystemService(AUDIO_SERVICE) as AudioManager
volumeControlStream = AudioManager.STREAM_VOICE_CALL
am.mode = AudioManager.MODE_IN_COMMUNICATION
am.isSpeakerphoneOn = false//<= not working in android 12
}
private fun toggleSpeakerMode(){
am.isSpeakerphoneOn = !am.isSpeakerphoneOn // <= final value is always true in android 12
}
The above code works fine on older versions of android, but not in android 12 (emulator).
am.isSpeakerphoneOn is always true in android 12. Am I doing something wrong here? Or is it a bug in the emulator?

there is a new API call in Android 12/S/API 31, setCommunicationDevice(AudioDeviceInfo). for switching between speaker an built-in earpiece now we can use:
ArrayList<Integer> targetTypes = new ArrayList<>();
if (earpieceMode) {
targetTypes.add(AudioDeviceInfo.TYPE_BUILTIN_EARPIECE);
} else { // play out loud
targetTypes.add(AudioDeviceInfo.TYPE_BUILTIN_SPEAKER);
}
// more targetTypes may be added in some cases
// set up will pick and first available, so order matters
List<AudioDeviceInfo> devices = audioManager.getAvailableCommunicationDevices();
outer:
for (Integer targetType : targetTypes) {
for (AudioDeviceInfo device : devices) {
if (device.getType() == targetType) {
boolean result = audioManager.setCommunicationDevice(device);
Log.i("AUDIO_MANAGER", "setCommunicationDevice type:" + targetType + " result:" + result);
if (result) break outer;
}
}
}
mode change isn't needed (but for voip calls is strongly suggested) and my streams are AudioManager.STREAM_VOICE_CALL type (where applicable)

By default webrtc uses earpiece for voice playing.
However,alternatively You can call the setSpeakerphoneOn(false) that is defined in the AudioManager.java class.
Just pass false in this function parameter and it will disable the speaker phone in the call and earpiece will be used.
I have also tested it on the android 12 phones and it is working fine.
If issue still persist then you have some bug in your emulator.

How can I catch a stream from Webview and change it to VOICE_CALL Stream with AEC?

I am using Agora, and it has some issues. One of them is the speaker's voice comes out to the media sound.
On the browser, it can't control the media volume, So, I created an app to handle this. In the app, I dispatch the volume up/down button to control media volume.
However, this method created howling issue. So, I'd like to send the sound to STREAM_VOICE_CALL and use AEC(Acoustic Echo Cancellation) API on Android so that the sound comes out to the right stream and it can handle the echo problem.
what I wrote,
private fun enableVoiceCallMode() {
with(audioManager) {
volumeControlStream = AudioManager.STREAM_VOICE_CALL
setStreamVolume(
AudioManager.STREAM_VOICE_CALL,
audioManager.getStreamVolume(AudioManager.STREAM_VOICE_CALL),
0
)
}
}
But this didn't work.
And also, I tried to apply AEC like this:
private fun enableEchoCanceler() {
if (AcousticEchoCanceler.isAvailable() && aec == null) {
aec = AcousticEchoCanceler.create(audioManager.generateAudioSessionId())
aec?.enabled = true
} else {
aec!!.enabled = false
aec!!.release()
aec = null
}
}
private fun releaseEchoCanceler() {
aec!!.enabled = false
aec?.release()
aec = null
}
However, I don't know if AcousticEchoCanceler.create(audioManager.generateAudioSessionId()) is correct way or not.
please help me out.

Android Auto: How to return a large number of children on loadChildren() of MediaBrowserService?

I am currently trying to implement a MediaBrowserService to build a media app for Android Auto.
I followed the official Android Auto documentation (https://developer.android.com/training/cars/media#onLoadChildren) to implement theonLoadChildren function.
Following is a code snippet that I tried to show the content on the Android Auto screen:
override fun onLoadChildren(parentId: String, result: Result<MutableList<MediaBrowserCompat.MediaItem>>) {
...
if (parentId == NODE_LIBRARY_ALBUMS) {
val items = mutableListOf<MediaBrowserCompat.MediaItem>()
val albumList = LibraryManager.getAlbumList()
for (it in albumList) {
val descriptionBuilder = MediaDescriptionCompat.Builder()
.setTitle(it.albumName)
items.add(MediaBrowserCompat.MediaItem(descriptionBuilder.build(), MediaBrowserCompat.MediaItem.FLAG_BROWSABLE))
}
result.sendResult(items)
}
...
}
This works pretty well, when the number of items is small enough.
However, when the number of items is large (e.g., about 5,000 items), the following error appears:
E/JavaBinder: !!! FAILED BINDER TRANSACTION !!! (parcel size = 1339384)
I found that several other media apps (e.g., Samsung Music) that support Android Auto can show a large number of items.
Is there any way to return a large number of items on the onLoadChildren function, or is there any other way to solve this issue?
Thanks!

Probably you have to split the large data into a small pieces. For example, you have a list of 5000 items. So inside you MediaBrowserService in onLoadChildren do something like this
public fun onLoadChildren(parentId: String, result: Result<List<MediaBrowserCompat.MediaItem>>) {
if (MEDIA_ID_ROOT == parentId || itemsList.size > 100) {
fillMediaBrowsableResult(parentId, result);
}
else {
fillMediaPlayableResult(parentId, result);
}
}
//Split the large number of content to a parts
private fun fillMediaBrowsableResult(parentId: String, result: Result<List<MediaBrowserCompat.MediaItem>>) {
// Detect count of parts
val partsCount = itemsList.size / 100
if(itemsList.size % 100 > 0){
partsCount ++
}
val mediaItems = mutableListOf<MediaBrowserCompat.MediaItem>()
//Create parts in a loop
for(i in 0 until partsCount){
val mediaDescription = MediaDescriptionCompat.Builder()
.setMediaId(i) // This is your next parent in onLoadChildren when you click on it in AA
.setTitle("Part ${i + 1}")
.build();
val mediaItem =. MediaBrowserCompat.MediaItem(mediaDescription, MediaBrowserCompat.MediaItem.FLAG_BROWSABLE)
mediaItems.add(mediaItem)
}
result.sendResult(mediaItems)
}
private fun fillMediaPlayableResult(parentId: String, result: Result<List<MediaBrowserCompat.MediaItem>>){
val intParent = parentId.toInt()
val startPosition = intParent * 100 // where to start for this part
val stopPosition = (intParent + 1) * 100 // where to finish for this part
if(stopPosition > itemsList.size){
stopPosition = itemsList.size
}
val mediaItems = mutableListOf<MediaBrowserCompat.MediaItem>()
for(i in startPosition..stopPosition){
//Generate playable content for this part
val item = itemsList[i]
val mediaDescription = MediaDescriptionCompat.Builder()
.setMediaId(item.id)
.setTitle(item.albumTitle)
.build();
val mediaItem =. MediaBrowserCompat.MediaItem(mediaDescription, MediaBrowserCompat.MediaItem.FLAG_PLAYABLE)
mediaItems.add(mediaItem)
}
result.sendResult(mediaItems)
}
I didn't check this code, but I think the idea is clear.

If you look into Android SDK document:
Note: Android Auto and Android Automotive OS have strict limits on how
many media items they can display in each level of the menu. These
limits minimize distractions for drivers and help them operate your
app with voice commands. ...
So, I think the best approach is to limit # of media items in UX design. For what you saw from the other apps working with lots of media items, they might used Jetpack Media 2 for pagination.

How to set sound playback from external speaker?

There is a kind of weird issue, I am using oboe lib https://github.com/google/oboe, for sound playback. Of course you can choose sound playback output according to android settings
https://developer.android.com/reference/android/media/AudioDeviceInfo
So, if I need to set exact output chanel I need to set it to oboe lib.
By the way output chanal that I need is TYPE_BUILTIN_SPEAKER, but on some devices (sometimes, not constantly) I hear the sound from
TYPE_BUILTIN_EARPIECE
How I am doing this, I have such method to get needed chanel id
fun findAudioDevice(app: Application,
deviceFlag: Int,
deviceType: Int): AudioDeviceInfo?
{
var result: AudioDeviceInfo? = null
val manager = app.getSystemService(Context.AUDIO_SERVICE) as AudioManager
val adis = manager.getDevices(deviceFlag)
for (adi in adis)
{
if (adi.type == deviceType)
{
result = adi
break
}
}
return result
}
How I use it
val id = getAudioDeviceInfoId(getBuildInSpeakerInfo())
private fun getBuildInSpeakerInfo(): AudioDeviceInfo?
{
return com.tetavi.ar.basedomain.utils.Utils.findAudioDevice( //
getApplication<Application>(), //
AudioManager.GET_DEVICES_OUTPUTS, //
AudioDeviceInfo.TYPE_BUILTIN_SPEAKER //
)
}
private fun getAudioDeviceInfoId(info: AudioDeviceInfo?): Int
{
var result = -1
if (info != null)
{
result = info.id
}
return result
}
And eventually I need to set this id to oboe lib. Oboe lib is native lib, so with JNI I pass this id and set it
oboe::Result oboe_engine::createPlaybackStream()
{
oboe::AudioStreamBuilder builder;
const oboe::SharingMode sharingMode = oboe::SharingMode::Exclusive;
const int32_t sampleRate = mBackingTrack->getSampleRate();
const oboe::AudioFormat audioFormat = oboe::AudioFormat::Float;
const oboe::PerformanceMode performanceMode = oboe::PerformanceMode::PowerSaving;
builder.setSharingMode(sharingMode)
->setPerformanceMode(performanceMode)
->setFormat(audioFormat)
->setCallback(this)
->setSampleRate(sampleRate);
if (m_output_playback_chanel_id != EMPTY_NUM)
{
//set output playback chanel (like internal or external speaker)
builder.setDeviceId(m_output_playback_chanel_id); <------------- THIS LINE
}
return builder.openStream(&mAudioStream);
}
So, actually issue is that on some devices (sometimes, not constantly) I still hear that sound playback goes from internal speaker TYPE_BUILTIN_EARPIECE inspite of I set directly that I need to use TYPE_BUILTIN_SPEAKER
I checked a few times the flow, from moment that I get this id (it is acctually is 3) and up to the moment when I set it as a param to oboe lib, but still sometimes I hear sound from internal speaker.
So, question is - if I miss something here? Maybe some trick should be implemented or something else?

How to close an Android app using UiAutomator?

How can I close an especific Android app using UiAutomator API?
Like when you manually press the Recents button and swipe the app you want to close.

Better way (not device, OS version, UI or orientation specific):
Runtime.getRuntime().exec(new String[] {"am", "force-stop", "pkg.name.of.your.app"});
Tested and working on a Nexus 5X with android 6.0

The best option would be to use getUiDevice.pressRecentApps, this will load up the recent apps for you, then take a screenshot using the uiautomator viewerso you have a view of the xml of the screen that has been loaded. You can then use this xml to select the object you wish to swipe using
UiObject app = new UIObject(new UiSelector().resourceId("The id of the app");
app.swipeLeft(100);
or right
This should be able to close your app. The xml will depend on what style of android you are using and the device.

This is how I kill all android apps at once with uiautomator:
public static void killApps()
{
UiDevice device = UiDevice.getInstance(InstrumentationRegistry.getInstrumentation());
try
{
device.pressHome();
device.pressRecentApps();
// Clear all isn't always visible unless you scroll all apps down
int height = device.getDisplayHeight();
int width = device.getDisplayWidth();
device.swipe(width/2,height/2, width/2, height, 50);
UiObject clear = device.findObject(new UiSelector()
.resourceId("com.android.systemui:id/button")
.text("CLEAR ALL")
);
if (clear.exists())
{
clear.click();
}
}
catch (RemoteException e)
{
e.printStackTrace();
}
catch (UiObjectNotFoundException e)
{
e.printStackTrace();
}
}

Building on the solution from #user597159 I got the following to close all applications on a Pixel 2 for Firebase Test Lab (i.e. the "walleye" device type):
private void killAllApps() throws Exception {
boolean keepSwiping = true;
int maxSwipeAttempts = 10;
uiDevice.pressRecentApps();
for (int swipeAttempt=0; swipeAttempt<maxSwipeAttempts && keepSwiping; swipeAttempt++) {
int height = uiDevice.getDisplayHeight();
int width = uiDevice.getDisplayWidth();
uiDevice.swipe(width / 2, height / 2, width, height / 2, 50);
UiObject clearAll1 = uiDevice.findObject(new UiSelector().text("Clear all"));
UiObject clearAll2 = uiDevice.findObject(new UiSelector().textStartsWith("Clear all"));
UiObject clearAll3 = uiDevice.findObject(new UiSelector().textContains("Clear all"));
UiObject clear = clearAll1.exists() ? clearAll1 :
(clearAll2.exists() ? clearAll2 : clearAll3);
if (clear.exists()) {
Logger.debug(TAG, "Attempting to close app by killAllApps and found clear=all button on swipeAttempt=" + swipeAttempt);
clear.click();
keepSwiping = false;
} else {
Logger.debug(TAG, "Attempting to close app by killAllApps but have to keep swiping swipeAttempt=" + swipeAttempt);
keepSwiping = true;
}
}
}
Note on the Pixel 2, it is spelled "Clear all" not "CLEAR ALL".
I could not get some of the other solutions to work. I got UiObjectNotFoundException for the following:
app = uiDevice.findObject(new UiSelector().textContains("SDK Test App"));
And also for:
app = uiDevice.findObject(new UiSelector().className(com.locuslabs.android.sdk.SdkTestApplication.class));
In other words app.exists() returned false for these approaches that attempted to swipe up on the app to close on Pixel 2.

When it is just one app that will be in the recent app list, this worked for me.
if(mDevice.pressRecentApps()) {
Thread.sleep(1000);
int startX = 300; int startY =835; int endX = 1000; int endY = 835; // co-ordinates refer to x-axis from left of screen to right.
int steps = 8;// speed at which the app closes
mDevice.swipe(startX,startY,endX,endY,steps);
}

Here's a Kotlin answer that is similar to this answer. It adds an extension function to UiDevice to clear all tasks. I tested this on a Pixel 2 emulator.
fun UiDevice.clearAllTasks(swipeAttempts: Int = 10 ) {
pressRecentApps()
var currentAttempt = 1
val centerScreenX = displayWidth / 2
val centerScreenY = displayHeight / 2
while (currentAttempt <= swipeAttempts) {
Timber.d("Clear all tasks attempt $currentAttempt")
swipe(centerScreenX, centerScreenY, displayWidth, centerScreenY, 50)
val uiObject = findObject(UiSelector().text("Clear all"))
if (uiObject.exists()) {
uiObject.click()
break
} else {
currentAttempt++
}
}
}

So I took a little more comprehensive approach to this at it seemed quite unreliable with others answers. I use A LOT of custom extensions so will try to post most of them:
fun UiDevice.clearTasks(swipes: Int = 2) {
logInfo { message("clearTasks swipes:$swipes") }
pressHome()
wait()
pressRecentApps()
wait()
repeat(swipes) {
if (context.isPortrait)
swipe(centerScreenX, centerScreenY, centerScreenX, 50, 10)
else
swipe(centerScreenX, centerScreenY, 25, centerScreenY, 10)
wait()
}
}
fun UiDevice.wait(seconds: Int = defaultWaitTime) {
logInfo { message("wait:$seconds") }
waitForWindowUpdate(null, seconds * SecondLong)
waitForMoreIdle()
}
fun UiDevice.waitForMoreIdle(times: Int = 3) {
logInfo { message("waitForMoreIdle times:$times") }
repeat(times) { waitForIdle() }
}
val UiDevice.centerScreenX get() = displayWidth / 2
val UiDevice.centerScreenY get() = displayHeight / 2
val Context.isPortrait get() = resources.configuration.orientation == ORIENTATION_PORTRAIT
val context: Context get() = ApplicationProvider.getApplicationContext()
Note: I don't really on some text as it depends on language on phone that can be different. Also I like more this custom swipe times approach as I know how much tasks approximately I need to clear out most of the time. There is side effect of showing app launcher but who cares. Didn't find a way to detect it to cancel swiping yet.