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How to get BLE devices' names list by android app?

Hello I am making a bluetooth connecting android app.
I followed the instruction from developer.android.com
while I am testing my app, I look forward to it works properly, but it didn't.
I tried to get detected BLE devices names, but don't know the reason why it doesn't show me the devices name...
Arduino nano 33 IOT is adverstising bluetooth next to my android phone, and I am trying to detect it and get the Adrduino's BLE device name and address.
here is my MainActivity.java
public class MainActivity extends AppCompatActivity {
//View Contents Elements
public Button btnActivateBluetooth;
public Button btnSearchBluetooth;
public Button btnSendData;
public ListView lvSearchedDevice;
public ListView lvLog;
public TextView tvStatus;
public EditText etData;
//etc values
public ArrayAdapter<String> logAdapter;
private final int REQUEST_ENABLE_BT = 1;
private boolean mScanning = true;
//bluetooth values
public BluetoothAdapter btAdapter;
public BluetoothManager btManager;
private Handler handler;
#SuppressLint("MissingPermission")
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
//View Elements
btnSearchBluetooth = (Button) findViewById(R.id.btnSearchBluetooth);
btnSendData = (Button) findViewById(R.id.btnSendData);
lvSearchedDevice = (ListView) findViewById(R.id.lvSearchedDevice);
lvLog = (ListView) findViewById(R.id.log);
tvStatus = (TextView) findViewById(R.id.tvStatus);
etData = (EditText) findViewById(R.id.etData);
//etc
logAdapter = new ArrayAdapter<>(this, android.R.layout.simple_list_item_1);
lvLog.setAdapter(logAdapter);
handler = new Handler();
// Initializes Bluetooth adapter.
btManager = (BluetoothManager)getSystemService(Context.BLUETOOTH_SERVICE);
btAdapter = btManager.getAdapter();
// displays a dialog requesting user permission to enable Bluetooth.
if (btAdapter == null || !btAdapter.isEnabled()) {
Intent enableBtIntent = new Intent(BluetoothAdapter.ACTION_REQUEST_ENABLE);
startActivityForResult(enableBtIntent, REQUEST_ENABLE_BT);
}
btnSearchBluetooth.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
scanLeDevice(true);
}
});
}
//Scan devices
#SuppressLint("MissingPermission")
private void scanLeDevice(final boolean enable){
if(enable){
handler.postDelayed(new Runnable() {
#SuppressLint("MissingPermission")
#Override
public void run() {
btAdapter.stopLeScan(leScanCallback);
}
},5000);
btAdapter.startLeScan(leScanCallback);
}
else
{
btAdapter.stopLeScan(leScanCallback);
}
}
//Callback method
private BluetoothAdapter.LeScanCallback leScanCallback = new BluetoothAdapter.LeScanCallback() {
#Override
public void onLeScan(final BluetoothDevice device, int rssi, byte[] scanRecord) {
runOnUiThread(new Runnable() {
#SuppressLint("MissingPermission")
#Override
public void run() {
Toast.makeText(MainActivity.this, device.getName(), Toast.LENGTH_SHORT).show();
}
});
}
};
}
and this is my Arduino nano 33 IOT's code.
#include <ArduinoBLE.h>
BLEService Toothbrush("00001101-0000-1000-8000-00805F9B34FB");
BLEStringCharacteristic ToothbrushChar("00001101-0000-1000-8000-00805F9B34FB",BLEWrite|BLERead | BLENotify, 10);
void setup() {
Serial.begin(9600);
if(!BLE.begin()){
Serial.println("Starting BLE failed.");
while(1);
}
BLE.setLocalName("HayanToothbrush");
BLE.setAdvertisedService(Toothbrush);
Toothbrush.addCharacteristic(ToothbrushChar);
BLE.addService(Toothbrush);
BLE.advertise();
Serial.println("Bluetooth device active, wating for connections...");
}
void loop() {
BLEDevice central = BLE.central();
if(central) {
Serial.print("Connected to central : ");
Serial.println(central.address());
while(central.connected()){
}
Serial.print("Disconnected from central:");
Serial.println(central.address());
}
}
I add permissions in the Mainfest as below.
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
package="com.example.bluetooth0523">
<uses-permission android:name="android.permission.BLUETOOTH" />
<uses-permission android:name="android.permission.BLUETOOTH_ADMIN" />
<uses-permission android:name="android.permission.BLUETOOTH_SCAN" />
<uses-permission android:name="android.permission.BLUETOOTH_CONNECT" />
<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />
<uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION" />
<uses-permission android:name="android.permission.ACCESS_BACKGROUND_LOCATION" />
<uses-feature android:name="android.hardware.bluetooth_le" android:required="true"/>
<application
android:allowBackup="true"
android:dataExtractionRules="#xml/data_extraction_rules"
android:fullBackupContent="#xml/backup_rules"
android:icon="#mipmap/ic_launcher"
android:label="#string/app_name"
android:roundIcon="#mipmap/ic_launcher_round"
android:supportsRtl="true"
android:theme="#style/Theme.Bluetooth0523"
tools:targetApi="31">
<activity
android:name=".MainActivity"
android:exported="true">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
</application>
</manifest>
But it still doesn't find me scanned device name.
I think it's on LeScanCallBack problem.
When running startLeScan, It seems not running callback method.
in addition, I am running this app on SDK_VERSION_30
and Arduino nano IOT 33 is discoverable If I use the Bluetooth function that my phone has, not my application, it will be displayed in the scan result list.
I want to get scan result on my own app.
but don't know where is the problem.

Permissions must be declared and requested depending on Android version. Main differences are:
Target Android 12 or higher
BLUETOOTH_SCAN
Target Android 11 or lower
ACCESS_FINE_LOCATION
See Bluetooth permissions for details.

Android - Permission to use Camera and Write to External Storage

I am trying to ask for permission to use the Camera and Writing to External Storage.
My Main Activity is:
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
button.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
if(Build.VERSION.SDK_INT>=Build.VERSION_CODES.M)
{
if(checkSelfPermission(Manifest.permission.CAMERA)!= PackageManager.PERMISSION_GRANTED)
{
ActivityCompat.requestPermissions(MainActivity.this,new String[]{android.Manifest.permission.CAMERA});
}
}
if(ActivityCompat.checkSelfPermission(getApplicationContext(),
Manifest.permission.WRITE_EXTERNAL_STORAGE)!= PackageManager.PERMISSION_GRANTED)
{
ActivityCompat.requestPermissions(MainActivity.this,new String[]{android.Manifest.permission.WRITE_EXTERNAL_STORAGE},REQUEST_PERM_WRITE_STORAGE);
}
else
{
takePhoto(); // calls this method
}
}
});
}
I have included in my Manifest.xml:
<uses-permission android:name="android.permission.CAMERA"/>
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"/>
I get this error:
cannot find symbol method requestPermissions(MainActivity,String[])
cannot find symbol method checkSelfPermission(Context,String)
What is it that I am doing wrong. Thanks

For the request camera part try this
final int RequestCameraPermissionID = 1001;
ActivityCompat.requestPermissions(this,
new String[]{android.Manifest.permission.CAMERA},RequestCameraPermissionID);

Test interstitial ads not showing. Error code 3- no fill

So i want to implement a interstitial ad into my app. I am starting testing with the test ads and they don't work. I get error code 3 from onAdFailedToLoad() method.Also i've tried showing an interstitial from this example and it didn't work aswell https://github.com/googleads/googleads-mobile-android-examples. I tried to run it from a nougat os btw
Here is my code:
The setupAds()method is called in onCreate()
private void setupAds() {
//MobileAds.initialize(this, "AD_ID");
MobileAds.initialize(this,
"AD_ID");
mInterstitial=new InterstitialAd(this);
mInterstitial.setAdUnitId("AD_ID");
mInterstitial.setAdListener(new AdListener() {
#Override
public void onAdLoaded() {
Toast.makeText(PopupActivity.this, "onAdlOOADED", Toast.LENGTH_SHORT).show();
}
#Override
public void onAdFailedToLoad(int errorCode) {
Toast.makeText(PopupActivity.this, "onAdfailedtoload" + errorCode, Toast.LENGTH_SHORT).show();
}
#Override
public void onAdOpened() {
Toast.makeText(PopupActivity.this, "onAdOpened", Toast.LENGTH_SHORT).show();
}
#Override
public void onAdLeftApplication() {
Toast.makeText(PopupActivity.this, "onAdleftaplication", Toast.LENGTH_SHORT).show();
}
#Override
public void onAdClosed() {
Toast.makeText(PopupActivity.this, "onAdcLOASED", Toast.LENGTH_SHORT).show();
}
});
AdRequest request = new AdRequest.Builder().
addTestDevice(AdRequest.DEVICE_ID_EMULATOR)
.build();
mInterstitial.loadAd(request);
((Button) mView.findViewById(R.id.test_ad_button)).setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
if (mInterstitial.isLoaded()){
mInterstitial.show();
}
}
});
}
And i show the ad here :
if (!isFirstStarted()){
if (mInterstitial.isLoaded()){
mInterstitial.show();
}
}
And here is a snippet of the manifest:
<uses-permission android:name="com.android.launcher.permission.INSTALL_SHORTCUT" />
<uses-permission android:name="android.permission.INTERNET"/>
<uses-permission android:name="android.permission.ACCESS_NETWORK_STATE"/>
<application
android:allowBackup="true"
android:icon="#mipmap/ic_launcher_round"
android:label="#string/app_name"
android:roundIcon="#mipmap/ic_launcher_round"
android:supportsRtl="true"
android:theme="#style/AppTheme">
<meta-data
android:name="com.google.android.gms.ads.APPLICATION_ID"
android:value="ID"/>

This code works for me !
Note : In this example i used testing ads id and testing interstitial id.
MobileAds.initialize(LoginActivity.this, "ca-app-pub-3940256099942544~3347511713");
mInterstitialAd = new InterstitialAd(LoginActivity.this);
mInterstitialAd.setAdUnitId("ca-app-pub-3940256099942544/1033173712");
mInterstitialAd.loadAd(new AdRequest.Builder()
//.addTestDevice(AdRequest.DEVICE_ID_EMULATOR)
.build());
mInterstitialAd.setAdListener(new com.google.android.gms.ads.AdListener() {
#Override
public void onAdLoaded() {
mInterstitialAd.show();
super.onAdLoaded();
}
});

Check this Link .
ERROR_CODE_NO_FILL : The ad request was successful, but no ad was returned due to lack of ad inventory.

The errorCode 3 means that AdMob cannot fulfill your AD request.
According to the document of onAdFailedToLoad() method, there are 4 types of error.
errorCode 0: ERROR_CODE_INTERNAL_ERROR - Something happened internally; for instance, an invalid response was received from the ad server.
errorCode 1: ERROR_CODE_INVALID_REQUEST - The ad request was invalid; for instance, the ad unit ID was incorrect.
errorCode 2: ERROR_CODE_NETWORK_ERROR - The ad request was unsuccessful due to network connectivity.
errorCode 3: ERROR_CODE_NO_FILL - The ad request was successful, but no ad was returned due to lack of ad inventory. According to the AdMob Help Community, a policy violation also leads to errorCode 3.
Case 1 only happens by a careless developer. It should not happen. It is not user trigger-able.
Case 2 occurs when a user uses an AD-blocker or network connection is down. It is user trigger-able.
Case 0, case 2 and case 3 are not controllable by developers. I suggest that you need to deal with these cases in your app.

Allowing microphone access(permission) in WebView [Android Studio] [Java]

I am currently working on a music tuner that uses html5 and a webview to display the 'application'. I've written the all the permission required in manifest and I think for webview there's another permission required.
I am using this https://jbergknoff.github.io/guitar-tuner/ as a sample redirect page for now
Here's my manifest.xml
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.raynordev.projectrosin">
<uses-permission android:name="android.permission.INTERNET" />
<uses-permission android:name="android.permission.MICROPHONE" />
<uses-permission android:name="android.permission.RECORD_AUDIO" />
<uses-permission android:name="android.permission.INTERNET" />
<uses-feature android:name="android.hardware.audio.low_latency" />
<uses-feature android:name="android.hardware.audio.pro" />
<uses-feature android:name="android.hardware.microphone" android:required="true"/>
<application
android:allowBackup="true"
android:icon="#mipmap/ic_launcher"
android:label="#string/app_name"
android:supportsRtl="true"
android:theme="#style/AppTheme">
<activity
android:name=".MainActivity"
android:theme="#style/Theme.AppCompat.Light.NoActionBar">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
<activity android:name="com.raynordev.projectrosin.HomeActivity">
</activity>
</application>
</manifest>
Here's my .java
public class HomeActivity extends AppCompatActivity {
private WebView wv;
private String TAG = "HomeActivity";
private static final int REQUEST_INTERNET = 200;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_home);
WebView wv = (WebView) findViewById(R.id.webView);
wv.getSettings().setJavaScriptEnabled(true);
wv.getSettings().setJavaScriptCanOpenWindowsAutomatically(true);
wv.setWebViewClient(new WebViewClient());
wv.setWebChromeClient(new WebChromeClient());
wv.loadUrl("https://jbergknoff.github.io/guitar-tuner/");
}
}
If require more information from me, please let me know.
Thank you everyone!!

<uses-permission android:name="android.permission.MODIFY_AUDIO_SETTINGS" />
Example:
MainActivity
public class MainActivity extends AppCompatActivity {
private static final int MY_PERMISSIONS_REQUEST_RECORD_AUDIO = 101;
private ActivityMainBinding mBinding;
private PermissionRequest myRequest;
#Override
protected void onCreate(#Nullable Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
mBinding = DataBindingUtil.setContentView(this, R.layout.activity_main);
setWebView();
}
private void setWebView() {
mBinding.webView.getSettings().setJavaScriptEnabled(true);
mBinding.webView.getSettings().setJavaScriptCanOpenWindowsAutomatically(true);
mBinding.webView.setWebViewClient(new WebViewClient());
mBinding.webView.getSettings().setSaveFormData(true);
mBinding.webView.getSettings().setSupportZoom(false);
mBinding.webView.getSettings().setCacheMode(WebSettings.LOAD_NO_CACHE);
mBinding.webViemBinding.webView.getSettings().setPluginState(WebSettings.PluginState.ON);
mBinding.webView.setWebChromeClient(new WebChromeClient() {
#Override
public void onPermissionRequest(final PermissionRequest request) {
myRequest = request;
for (String permission : request.getResources()) {
switch (permission) {
case "android.webkit.resource.AUDIO_CAPTURE": {
askForPermission(request.getOrigin().toString(), Manifest.permission.RECORD_AUDIO, MY_PERMISSIONS_REQUEST_RECORD_AUDIO);
break;
}
}
}
}
});
mBinding.webView.loadUrl("<your url");
}
#Override
public void onBackPressed() {
if (mBinding.webView.canGoBack()) {
mBinding.webView.goBack();
} else {
super.onBackPressed();
}
}
#Override
public void onRequestPermissionsResult(int requestCode,
String permissions[], int[] grantResults) {
switch (requestCode) {
case MY_PERMISSIONS_REQUEST_RECORD_AUDIO: {
Log.d("WebView", "PERMISSION FOR AUDIO");
if (grantResults.length > 0
&& grantResults[0] == PackageManager.PERMISSION_GRANTED) {
// permission was granted, yay! Do the
// contacts-related task you need to do.
myRequest.grant(myRequest.getResources());
mBinding.webView.loadUrl("<your url>");
} else {
// permission denied, boo! Disable the
// functionality that depends on this permission.
}
}
// other 'case' lines to check for other
// permissions this app might request
}
}
public void askForPermission(String origin, String permission, int requestCode) {
Log.d("WebView", "inside askForPermission for" + origin + "with" + permission);
if (ContextCompat.checkSelfPermission(getApplicationContext(),
permission)
!= PackageManager.PERMISSION_GRANTED) {
// Should we show an explanation?
if (ActivityCompat.shouldShowRequestPermissionRationale(MainActivity.this,
permission)) {
// Show an expanation to the user *asynchronously* -- don't block
// this thread waiting for the user's response! After the user
// sees the explanation, try again to request the permission.
} else {
// No explanation needed, we can request the permission.
ActivityCompat.requestPermissions(MainActivity.this,
new String[]{permission},
requestCode);
}
} else {
myRequest.grant(myRequest.getResources());
}
}
}
Mainfest.xml:
<uses-permission android:name="android.permission.INTERNET" />
<uses-permission android:name="android.permission.MICROPHONE" />
<uses-permission android:name="android.permission.RECORD_AUDIO" />
<uses-permission android:name="android.permission.INTERNET" />
<uses-feature android:name="android.hardware.audio.low_latency" />
<uses-permission android:name="android.permission.MODIFY_AUDIO_SETTINGS" />
<uses-feature android:name="android.hardware.audio.pro" />
<uses-feature android:name="android.hardware.microphone"/>
Build.gradle:
android {
compileSdkVersion 26
defaultConfig {
applicationId "myapp.example.com.myapplication"
minSdkVersion 21
targetSdkVersion 21
versionCode 1
versionName "1.0"
}
buildTypes {
release {
minifyEnabled false
proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
}
}

Summarising, you need the following components:
The MODIFY_AUDIO_SETTINGS permission.
A WebChromeClient and listen to callbacks for onPermissionRequest
Inside this callback, check for the the resources coming in the request object, create a global variable of this request object, iterate and look for specific permission inside the PermissionRequest class, ex. PermissionRequest.RESOURCE_VIDEO_CAPTURE which translates to the Manifest.permission.CAMERA permission, check if your app has this permission or not, using any mechanism you wish if not, request, if yes do 4.
In the permission callback or if the permission is granted, use the request object to grant the permission ex. request.grant(new String[]{PermissionRequest.RESOURCE_VIDEO_CAPTURE}) and you're good to go.
snippet:
webView.webChromeClient = object: WebChromeClient(){
override fun onPermissionRequest(request: PermissionRequest?) {
super.onPermissionRequest(request)
webkitPermissionRequest = request
request?.resources?.forEach {
when(it){
PermissionRequest.RESOURCE_AUDIO_CAPTURE-> {
askForWebkitPermission(it, Manifest.permission.RECORD_AUDIO, REQUEST_CODE_PERMISSION_AUDIO)
}
PermissionRequest.RESOURCE_VIDEO_CAPTURE->{
askForWebkitPermission(it, Manifest.permission.CAMERA, REQUEST_CODE_PERMISSION_CAMERA)
}
}
}
}
}
private fun askForWebkitPermission(webkitPermission: String, androidPermission: String, requestCode: Int){
val context = activity?: return
if (context.hasPermission(androidPermission)){
webkitPermissionRequest!!.grant(arrayOf(webkitPermission))
}else{
requestPermissions(arrayOf(androidPermission), requestCode)
}
}
Hope this helps.
Google's sample for the same: https://github.com/googlesamples/android-PermissionRequest

its problems for reload the webview , after too much research , found this code and create this below code :-
mwebView.setWebChromeClient(new WebChromeClient() {
#Override
public void onPermissionRequest(final PermissionRequest request) {
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP) {
myRequest = request;
for (String permission : request.getResources()) {
if (permission.equals("android.webkit.resource.AUDIO_CAPTURE")) {
demandForPermission(request.getOrigin().toString(), Manifest.permission.RECORD_AUDIO, MY_PERMISSIONS_REQUEST_RECORD_AUDIO);
} else {
myRequest.grant(request.getResources());
}
}
}
}
#Override
public void onPermissionRequestCanceled(PermissionRequest request) {
super.onPermissionRequestCanceled(request);
}
more info in this link Android Webview

How handle the microphone mute?

I want to use ContentObserver for handling microphone state. But it's doesn't work. Nothing comes in method onChange.
public class MainActivity extends Activity implements OnClickListener{
AudioManager amAudioManager;
#Override
protected void onCreate(Bundle savedInstanceState) {
amAudioManager = (AudioManager)getSystemService(Context.AUDIO_SERVICE);
getContentResolver().registerContentObserver(
System.getUriFor(System.MUTE_STREAMS_AFFECTED),
false, mMuteObserver);
}
private ContentObserver mMuteObserver = new ContentObserver(new Handler()) {
#Override
public void onChange(boolean selfChange) {
super.onChange(selfChange);
amAudioManager.setMicrophoneMute(false);
}
};
#Override
public void onClick(View v) {
int id = v.getId();
//just for test functional
amAudioManager.setMicrophoneMute(true);
}
}
Android manifest file permissions:
<uses-permission android:name="android.permission.INTERNET" />
<uses-permission android:name="android.permission.WRITE_CONTACTS" />
<uses-permission android:name="android.permission.READ_PHONE_STATE" />
<uses-permission android:name="android.permission.MODIFY_AUDIO_SETTINGS" />
<uses-permission android:name="android.permission.RECORD_AUDIO" />**