Develop Reference

Write to function, is called multi time in request body

I have a progreesBar for uploading with retrofit and I implementation that with some of examples.
my problem is 'WriteTo' function in my custom requestBody class.
This function send progress value for use in my progressBar but this function is called twice. I used debugger and I think some interceptors call WriteTo function.
Let me explain the problem more clearly,When I click Upload button, The number of progress bar reaches one hundred and then it starts again from zero.
Some of the things I did:
I removed HttpLoggingInterceptor.
I used a boolean variable for check that 'writeTo' don't post anything the first time
I don't have any extra interceptors
Also I read this topics:
Retrofit 2 RequestBody writeTo() method called twice
using Retrofit2/okhttp3 upload file,the upload action always performs twice,one fast ,and other slow
Interceptor Problem
My codes:
ProgressRequestBody class
class ProgressRequestBody : RequestBody() {
var mutableLiveData = MutableLiveData<Int>()
lateinit var mFile: File
lateinit var contentType: String
companion object {
private const val DEFAULT_BUFFER_SIZE = 2048
}
override fun contentType(): MediaType? {
return "$contentType/*".toMediaTypeOrNull()
}
#Throws(IOException::class)
override fun contentLength(): Long {
return mFile.length()
}
#Throws(IOException::class)
override fun writeTo(sink: BufferedSink) {
val fileLength = mFile.length()
val buffer = ByteArray(DEFAULT_BUFFER_SIZE)
val `in` = FileInputStream(mFile)
var uploaded: Long = 0
`in`.use { `in` ->
var read: Int
while (`in`.read(buffer).also { read = it } != -1) {
val percentage = (100 * uploaded / fileLength).toInt()
mutableLiveData.postValue(percentage)
uploaded += read.toLong()
sink.write(buffer, 0, read)
}
}
}
}
private fun upload(file: File, fileType: FileType) {
val fileBody = ProgressRequestBody()
fileBody.mFile = file
fileBody.contentType = file.name
uploadImageJob = viewModelScope.launch(Dispatchers.IO) {
val body = MultipartBody.Part.createFormData("File", file.name, fileBody)
fileUploadRepo.upload(body).catch {
// ...
}.collect {
when (it) {
// ...
}
}
}
}
In my fragment I use liveData for collect progressBar progress value.

ExoPlayer problems trying to download current track

I am using Exoplayer to create my own music player. I am also adding the option to download the track but I have a problem when I am trying to download the track that I am playing. I add a notification to the download to check the progress of the download and it appears but it even doesn't start. What I think is that it might have some kind of problem with the buffering cache and the download since they are stored in the same folder.
To download the tracks I do the following:
override fun addDownloadTrack(track: Track) {
getIfTrackIsCached.run({ isCached ->
if (!isCached) {
val data = Util.toByteArray(track.title.byteInputStream())
val downloadRequest =
DownloadRequest(track.id, DownloadRequest.TYPE_PROGRESSIVE, Uri.parse(track.href), Collections.emptyList(), track.id, data)
DownloadService.sendAddDownload(context, ExoPlayerDownloadService::class.java, downloadRequest, false)
}
}, ::onError, GetIfTrackIsCached.Params(track.id))
}
This is the DownloadService:
class ExoPlayerDownloadService : DownloadService(
FOREGROUND_NOTIFICATION_ID,
DEFAULT_FOREGROUND_NOTIFICATION_UPDATE_INTERVAL,
Constants.CHANNEL_DOWNLOAD_ID,
R.string.exo_download_notification_channel_name) {
private val manager: DownloadManager by inject()
private val channelIsCached: ChannelPublisher<CachedMedia> by inject(PUBLISHER_IS_CACHED)
private val notificationHelper: DownloadNotificationHelper by inject()
private var nextNotificationId: Int = FOREGROUND_NOTIFICATION_ID
override fun onCreate() {
super.onCreate()
if (!manager.isInitialized) {
manager.maxParallelDownloads = MAX_PARALLEL_DOWNLOADS
}
}
override fun getDownloadManager(): DownloadManager = manager
override fun getForegroundNotification(downloads: MutableList<Download>?): Notification {
var text = ""
var index = 1
downloads?.forEach { text += "${if (downloads.size > 1) "${index++} - " else ""}${Util.fromUtf8Bytes(it.request.data)}\n" }
return notificationHelper.buildProgressNotification(R.drawable.ic_stat_downloading, null, text, downloads)
}
override fun getScheduler(): Scheduler? = null
override fun onDownloadChanged(download: Download?) {
val notification = when (download?.state) {
Download.STATE_COMPLETED -> {
channelIsCached.publish(CachedMedia(download.request.id, true))
notificationHelper.buildDownloadCompletedNotification(R.drawable.ic_stat_download_complete, null, Util.fromUtf8Bytes(download.request.data))
}
Download.STATE_FAILED ->
notificationHelper.buildDownloadFailedNotification(R.drawable.ic_stat_download_failed, null, Util.fromUtf8Bytes(download.request.data))
else -> null
}
notification?.let { NotificationUtil.setNotification(this#ExoPlayerDownloadService, ++nextNotificationId, it) }
}
companion object {
private const val MAX_PARALLEL_DOWNLOADS = 3
private const val FOREGROUND_NOTIFICATION_ID = 2000
}
}
And to create the cache I use this:
SimpleCache(File(androidContext().cacheDir, CACHE_MEDIA_FOLDER), NoOpCacheEvictor(), get<DatabaseProvider>())
How can I avoid conflicts between buffering cache and downloaded files?

I had this issue also, and found the solution!
The downloading documentation states
The CacheDataSource.Factory should be configured as read-only to avoid downloading that content as well during playback.
To do this you must call setCacheWriteDataSinkFactory(null) on your CacheDataSource.Factory object.
This will prevent the stream from writing to the cache, allowing the downloader to write as expected.

Only raw audio data broadcast without using mic or speaker

I am only able to broadcast audio alone using mic and speaker, and if I use setExternalAudioSource method, then the broadcast encounter with some heavy unwanted noise. I just want to broadcast the raw audio data alone without using mic, speaker and unwanted noise.
private val PERMISSION_REQ_ID_RECORD_AUDIO = 22
private var mRtcEngine: RtcEngine? = null// Tutorial Step 1
private val mRtcEventHandler = object : IRtcEngineEventHandler() { // Tutorial Step 1
override fun onUserOffline(uid: Int, reason: Int) { // Tutorial Step 4
//runOnUiThread { onRemoteUserLeft(uid, reason) }
}
override fun onUserMuteAudio(uid: Int, muted: Boolean) { // Tutorial Step 6
// runOnUiThread { onRemoteUserVoiceMuted(uid, muted) }
}
}
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
setContentView(R.layout.activity_main)
if (checkSelfPermission(Manifest.permission.RECORD_AUDIO, PERMISSION_REQ_ID_RECORD_AUDIO)) {
createRtcChannel()
}
}
fun checkSelfPermission(permission: String, requestCode: Int): Boolean {
if (ContextCompat.checkSelfPermission(this,
permission) != PackageManager.PERMISSION_GRANTED) {
ActivityCompat.requestPermissions(this,
arrayOf(permission),
requestCode)
return false
}
return true
}
private fun createRtcChannel() {
initializeAgoraEngine() // Tutorial Step 1
joinChannel()
}
private fun initializeAgoraEngine() {
try {
mRtcEngine = RtcEngine.create(this, getString(R.string.agora_app_id), mRtcEventHandler)
//set the channel as live broadcast mode
mRtcEngine?.setChannelProfile(Constants.CHANNEL_PROFILE_LIVE_BROADCASTING)
mRtcEngine?.setClientRole(Constants.CLIENT_ROLE_BROADCASTER)
} catch (e: Exception) {
}
}
private fun joinChannel() {
mRtcEngine?.joinChannel(null, "voiceDemoChannel1", "Extra Optional Data", 0) // if you do not specify the uid, we will generate the uid for you
val payload = IOUtils.toByteArray(assets.openFd("ringtone.mp3").createInputStream())
mRtcEngine?.setExternalAudioSource(
true,
8000,
1 );
mRtcEngine?.pushExternalAudioFrame(
payload,
1000
)
}
Is this possible using agora or is there any alternative to it?

Reasons can cause the noise:
Your source audio PCM samples are noisy by themselves
Engine bugs
The sample rate you set is wrong
For the first one, you can check your PCM samples directly. For the 2nd, as there are already many people using, it's rare to be true. So I woulld suguest you to check the sample rate if you are sure your source PCM samples are good.
Also, you can set up the APM option before you join channel to enable audio enhancement for external source, by
setParameters("{\"che.audio.override_apm\":true}")

Chain Requests Kotlin Coroutines

I have an array of URLs, each providing a zip file. I want to download them and store them in my app folders, inside the internal memory.
Question:
Since I do not know the number of URLs I will need to access, what is the best way to go about this? I am just beginning to work with Kotlin coroutines.
This is my 'download from url' method
fun downloadResourceArchiveFromUrl(urlString: String, context: Context): Boolean {
Timber.d("-> Started downloading resource archive.. $urlString")
lateinit var file: File
try {
val url = URL(urlString)
val urlConn = url.openConnection()
urlConn.readTimeout = 5000
urlConn.connectTimeout = 10000
val inputStream = urlConn.getInputStream()
val buffInStream = BufferedInputStream(inputStream, 1024 * 5)
val fileNameFromUrl = urlString.substringAfterLast("/")
file = File(context.getDir("resources", Context.MODE_PRIVATE) , fileNameFromUrl)
val outStream = FileOutputStream(file)
val buff = ByteArray(5 * 1024)
while (buffInStream.read(buff) != -1){
outStream.write(buff, 0, buffInStream.read(buff))
}
outStream.flush()
outStream.close()
buffInStream.close()
} catch (e: Exception) {
e.printStackTrace()
Timber.d("Download finished with exception: ${e.message} -<")
return false
}
Timber.d("Download finished -<")
return true
}
Could you simply create a loop and call download method each time?
for (i in resources.indices) {
asyncAwait {
downloadResourcesFromUrl(resources[i].url, context)
return#asyncAwait
}
Also, is it a good idea to do this synchronously? Wait for every file to download then proceed to the next one?

Turn your blocking download function into a suspending one:
suspend fun downloadResourceArchiveFromUrl(
urlString: String, context: Context
): Boolean = withContext(Dispatchers.IO) {
... your function body
}
Now run your loop inside a coroutine you launch:
myActivity.launch {
resources.forEach {
val success = downloadResourceArchiveFromUrl(it.url, context)
... react to success/failure ...
}
}
Also be sure to properly implement structured concurrency on your activity.

Is it possible to use WebView in Worker?

Background
I'm trying to load some URL in the background, but in the same way WebView loads it in an Activity.
There are multiple reasons developers would want it (and requested about it here) , such as running JavaScript without Activity, caching, monitor websites changes, scrapping ...
The problem
It seems that on some devices and Android versions (Pixel 2 with Android P, for example), this works fine on Worker , but on some others (probably on older versions of Android), I can do it well and safely only on a foreground service with on-top view using the SYSTEM_ALERT_WINDOW permission.
Thing is, we need to use it in the background, as we have a Worker already that is intended for other things. We would prefer not to add a foreground service just for that, as it would make things complex, add a required permission, and would make a notification for the user as long as it needs to do the work.
What I've tried&found
Searching the Internet, I can find only few mention this scenario (here and here). The main solution is indeed to have a foreground service with on-top view.
In order to check if the website loads fine, I've added logs in various callbacks, including onProgressChanged , onConsoleMessage, onReceivedError , onPageFinished , shouldInterceptRequest, onPageStarted . All part of WebViewClient and WebChromeClient classes.
I've tested on websites that I know should write to the console, a bit complex and take some time to load, such as Reddit and Imgur .
It is important to let JavaScript enabled, as we might need to use it, and websites load as they should when it's enabled, so I've set javaScriptEnabled=true . I've noticed there is also javaScriptCanOpenWindowsAutomatically , but as I've read this isn't usually needed, so I didn't really use it. Plus it seems that enabling it causes my solutions (on Worker) to fail more, but maybe it's just a coincidence . Also, it's important to know that WebView should be used on the UI thread, so I've put its handling on a Handler that is associated with the UI thread.
I've tried to enable more flags in WebSettings class of the WebView, and I also tried to emulate that it's inside of a container, by measuring it.
Tried to delay the loading a bit, and tried to load an empty URL first. On some cases it seemed to help, but it's not consistent .
Doesn't seem like anything helped, but on some random cases various solutions seemed to work nevertheless (but not consistent).
Here's my current code, which also includes some of what I've tried (project available here) :
Util.kt
object Util {
#SuppressLint("SetJavaScriptEnabled")
#UiThread
fun getNewWebView(context: Context): WebView {
val webView = WebView(context)
// val screenWidth = context.resources.displayMetrics.widthPixels
// val screenHeight = context.resources.displayMetrics.heightPixels
// webView.measure(screenWidth, screenHeight)
// webView.layout(0, 0, screenWidth, screenHeight)
// webView.measure(600, 400);
// webView.layout(0, 0, 600, 400);
val webSettings = webView.settings
webSettings.javaScriptEnabled = true
// webSettings.loadWithOverviewMode = true
// webSettings.useWideViewPort = true
// webSettings.javaScriptCanOpenWindowsAutomatically = true
// if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.JELLY_BEAN) {
// webSettings.allowFileAccessFromFileURLs = true
// webSettings.allowUniversalAccessFromFileURLs = true
// }
webView.webChromeClient = object : WebChromeClient() {
override fun onProgressChanged(view: WebView?, newProgress: Int) {
super.onProgressChanged(view, newProgress)
Log.d("appLog", "onProgressChanged:$newProgress " + view?.url)
}
override fun onConsoleMessage(consoleMessage: ConsoleMessage?): Boolean {
if (consoleMessage != null)
Log.d("appLog", "webViewConsole:" + consoleMessage.message())
return super.onConsoleMessage(consoleMessage)
}
}
webView.webViewClient = object : WebViewClient() {
override fun onReceivedError(view: WebView, request: WebResourceRequest, error: WebResourceError) {
Log.d("appLog", "error $request $error")
}
override fun onPageFinished(view: WebView?, url: String?) {
super.onPageFinished(view, url)
Log.d("appLog", "onPageFinished:$url")
}
override fun shouldInterceptRequest(view: WebView, request: WebResourceRequest): WebResourceResponse? {
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP)
Log.d("appLog", "shouldInterceptRequest:${request.url}")
else
Log.d("appLog", "shouldInterceptRequest")
return super.shouldInterceptRequest(view, request)
}
override fun onPageStarted(view: WebView?, url: String?, favicon: Bitmap?) {
super.onPageStarted(view, url, favicon)
Log.d("appLog", "onPageStarted:$url hasFavIcon?${favicon != null}")
}
}
return webView
}
#TargetApi(Build.VERSION_CODES.M)
fun isSystemAlertPermissionGranted(#NonNull context: Context): Boolean {
return Build.VERSION.SDK_INT <= Build.VERSION_CODES.LOLLIPOP_MR1 || Settings.canDrawOverlays(context)
}
fun requestSystemAlertPermission(context: Activity?, fragment: Fragment?, requestCode: Int) {
if (Build.VERSION.SDK_INT <= Build.VERSION_CODES.LOLLIPOP_MR1)
return
//http://developer.android.com/reference/android/Manifest.permission.html#SYSTEM_ALERT_WINDOW
val packageName = if (context == null) fragment!!.activity!!.packageName else context.packageName
var intent = Intent(Settings.ACTION_MANAGE_OVERLAY_PERMISSION, Uri.parse("package:$packageName"))
try {
if (fragment != null)
fragment.startActivityForResult(intent, requestCode)
else
context!!.startActivityForResult(intent, requestCode)
} catch (e: Exception) {
intent = Intent(Settings.ACTION_MANAGE_APPLICATIONS_SETTINGS)
if (fragment != null)
fragment.startActivityForResult(intent, requestCode)
else
context!!.startActivityForResult(intent, requestCode)
}
}
/**
* requests (if needed) system alert permission. returns true iff requested.
* WARNING: You should always consider checking the result of this function
*/
fun requestSystemAlertPermissionIfNeeded(activity: Activity?, fragment: Fragment?, requestCode: Int): Boolean {
val context = activity ?: fragment!!.activity
if (isSystemAlertPermissionGranted(context!!))
return false
requestSystemAlertPermission(activity, fragment, requestCode)
return true
}
}
MyService.kt
class MyService : Service() {
override fun onBind(intent: Intent): IBinder? = null
override fun onCreate() {
super.onCreate()
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) {
val notificationManager = getSystemService(Context.NOTIFICATION_SERVICE) as NotificationManager
run {
//general
val channel = NotificationChannel("channel_id__general", "channel_name__general", NotificationManager.IMPORTANCE_DEFAULT)
channel.enableLights(false)
channel.setSound(null, null)
notificationManager.createNotificationChannel(channel)
}
}
val builder = NotificationCompat.Builder(this, "channel_id__general")
builder.setSmallIcon(android.R.drawable.sym_def_app_icon).setContentTitle(getString(R.string.app_name))
startForeground(1, builder.build())
}
#SuppressLint("SetJavaScriptEnabled")
override fun onStartCommand(intent: Intent?, flags: Int, startId: Int): Int {
val windowManager = getSystemService(Context.WINDOW_SERVICE) as WindowManager
val params = WindowManager.LayoutParams(
android.view.ViewGroup.LayoutParams.WRAP_CONTENT,
android.view.ViewGroup.LayoutParams.WRAP_CONTENT,
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) WindowManager.LayoutParams.TYPE_APPLICATION_OVERLAY else WindowManager.LayoutParams.TYPE_PHONE,
WindowManager.LayoutParams.FLAG_NOT_FOCUSABLE or WindowManager.LayoutParams.FLAG_NOT_TOUCHABLE,
PixelFormat.TRANSLUCENT
)
params.gravity = Gravity.TOP or Gravity.START
params.x = 0
params.y = 0
params.width = 0
params.height = 0
val webView = Util.getNewWebView(this)
// webView.loadUrl("https://www.google.com/")
// webView.loadUrl("https://www.google.com/")
// webView.loadUrl("")
// Handler().postDelayed( {
// webView.loadUrl("")
webView.loadUrl("https://imgur.com/a/GPlx4?desktop=1")
// },5000L)
// webView.loadUrl("https://imgur.com/a/GPlx4?desktop=1")
windowManager.addView(webView, params)
return super.onStartCommand(intent, flags, startId)
}
}
MainActivity.kt
class MainActivity : AppCompatActivity() {
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
setContentView(R.layout.activity_main)
startServiceButton.setOnClickListener {
if (!Util.requestSystemAlertPermissionIfNeeded(this, null, REQUEST_DRAW_ON_TOP))
ContextCompat.startForegroundService(this#MainActivity, Intent(this#MainActivity, MyService::class.java))
}
startWorkerButton.setOnClickListener {
val workManager = WorkManager.getInstance()
workManager.cancelAllWorkByTag(WORK_TAG)
val builder = OneTimeWorkRequest.Builder(BackgroundWorker::class.java).addTag(WORK_TAG)
builder.setConstraints(Constraints.Builder().setRequiredNetworkType(NetworkType.CONNECTED)
.setRequiresCharging(false).build())
builder.setInitialDelay(5, TimeUnit.SECONDS)
workManager.enqueue(builder.build())
}
}
override fun onActivityResult(requestCode: Int, resultCode: Int, data: Intent?) {
super.onActivityResult(requestCode, resultCode, data)
if (requestCode == REQUEST_DRAW_ON_TOP && Util.isSystemAlertPermissionGranted(this))
ContextCompat.startForegroundService(this#MainActivity, Intent(this#MainActivity, MyService::class.java))
}
class BackgroundWorker : Worker() {
val handler = Handler(Looper.getMainLooper())
override fun doWork(): Result {
Log.d("appLog", "doWork started")
handler.post {
val webView = Util.getNewWebView(applicationContext)
// webView.loadUrl("https://www.google.com/")
webView.loadUrl("https://www.google.com/")
// webView.loadUrl("")
// Handler().postDelayed({
// // webView.loadUrl("")
//// webView.loadUrl("https://imgur.com/a/GPlx4?desktop=1")
// webView.loadUrl("https://www.reddit.com/")
//
// }, 1000L)
// webView.loadUrl("https://imgur.com/a/GPlx4?desktop=1")
}
Thread.sleep(20000L)
Log.d("appLog", "doWork finished")
return Worker.Result.SUCCESS
}
}
companion object {
const val REQUEST_DRAW_ON_TOP = 1
const val WORK_TAG = "WORK_TAG"
}
}
activity_main.xml
<LinearLayout
xmlns:android="http://schemas.android.com/apk/res/android" xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent" android:layout_height="match_parent" android:gravity="center"
android:orientation="vertical" tools:context=".MainActivity">
<Button
android:id="#+id/startServiceButton" android:layout_width="wrap_content" android:layout_height="wrap_content"
android:text="start service"/>
<Button
android:id="#+id/startWorkerButton" android:layout_width="wrap_content" android:layout_height="wrap_content"
android:text="start worker"/>
</LinearLayout>
gradle file
...
dependencies {
implementation fileTree(dir: 'libs', include: ['*.jar'])
implementation "org.jetbrains.kotlin:kotlin-stdlib-jdk7:$kotlin_version"
implementation 'androidx.appcompat:appcompat:1.0.0-rc02'
implementation 'androidx.core:core-ktx:1.0.0-rc02'
implementation 'androidx.constraintlayout:constraintlayout:1.1.2'
def work_version = "1.0.0-alpha08"
implementation "android.arch.work:work-runtime-ktx:$work_version"
implementation "android.arch.work:work-firebase:$work_version"
}
manifest
<manifest package="com.example.webviewinbackgroundtest" xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools">
<uses-permission android:name="android.permission.FOREGROUND_SERVICE"/>
<uses-permission android:name="android.permission.INTERNET"/>
<uses-permission android:name="android.permission.SYSTEM_ALERT_WINDOW"/>
<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"
tools:ignore="AllowBackup,GoogleAppIndexingWarning">
<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=".MyService" android:enabled="true" android:exported="true"/>
</application>
</manifest>
The questions
Main question: Is it even possible to use a WebView within Worker?
How come it seems to work fine on Android P in a Worker, but not on others?
How come sometimes it did work on a Worker?
Is there an alternative, either to do it in Worker, or having an alternative to WebView that is capable of the same operations of loading webpages and running Javascripts on them ?

I think we need another tool for these kind of scenarios. My honest opinion is, it's a WebView, a view after all, which is designed to display web pages. I know as we need to implement hacky solutions to resolve such cases, but I believe these are not webView concerns either.
What I think would be the solution is, instead of observing web page and listening javaScripts for changes, changes should be delivered to app by a proper message ( push / socket / web service ).
If it's not possible to do it this way, I believe request (https://issuetracker.google.com/issues/113346931) should not be "being able to run WebView in a service" but a proper addition to SDK which would perform operations you mentioned.