Develop Reference

Android telecom Connection private function (supportedAudioRoutes)

Why google dont provide this function for normal use (android.telecom.Connection)?
I need this function for disable bluetooth selection for my call. I think that in java we can use reflection for get this function, but im using Xamarin and its impossivel using reflection
/**
* Sets the supported audio routes.
*
* #param supportedAudioRoutes the supported audio routes as a bitmask.
* See {#link CallAudioState}
* #hide
*/
public final void setSupportedAudioRoutes(int supportedAudioRoutes) {
if ((supportedAudioRoutes
& (CallAudioState.ROUTE_EARPIECE | CallAudioState.ROUTE_SPEAKER)) == 0) {
throw new IllegalArgumentException(
"supported audio routes must include either speaker or earpiece");
}
if (mSupportedAudioRoutes != supportedAudioRoutes) {
mSupportedAudioRoutes = supportedAudioRoutes;
for (Listener l : mListeners) {
l.onSupportedAudioRoutesChanged(this, mSupportedAudioRoutes);
}
}
}

The answer ist simple and easy. You are not supposed to use it.
Please read the specification and understand that Represents does not mean Controls.

How to get my Android device's CPU and processor information programatically?

Hope you all are safe and doing well.Currently i integrated some SDK for auto capturing the documents.SDK team now updated their minimum hardware requirements for auto capture feature,if these requirement does not meet, user have to manually capture documents.Those requirements are1. RAM should be at least 2GB.
2. Systemt chip              1. Qualcomm Snapdragon 800 series, minimum 820 or equivalent.              2. Qualcomm Snapdragon 600 series, minimum 630 or equivalent.             3. Qualcomm Snapdragon 700 series, minimum 710 or equivalent.3. CPU with              64-bit, quad-core
2.0 GHzHow to check these configurations programmatically in Android, so that i can navigate user appropriately in my application.Thanks in advanceCheers

With this method you can retrieve the information that you need.
try {
var holder = ""
val data = arrayOf("/system/bin/cat", "/proc/cpuinfo")
val byteArray = ByteArray(1024)
val processBuilder = ProcessBuilder(*data)
val process = processBuilder.start()
val inputStream = process.inputStream
while (inputStream.read(byteArray) != -1) {
holder += String(byteArray)
}
inputStream.close()
print(holder)
} catch (ex: IOException) {
ex.printStackTrace()
}

How to transfer images via Bluetooth (LE) to a desktop application

We are currently trying to implement the transmission of images from a mobile device (in this case an IPhone) to a desktop application. We tried already the Bluetooth Serial plugin which works fine for Android but does not list any devices when scanning for our desktop application.
To cover iOS support (AFAIK iOS only supports BluetoothLE), we reimplemented our desktop application to use BluetoothLE and behave like a peripheral. Also we altered our Ionic application to use BLE plugin.
Now BluetoothLE only supports the transmission of packages with the size of 20 Byte whilst our image is about 500kb big. So we could obviously split our image into chunks and transmit it with the following function (taken from this gist):
function writeLargeData(buffer) {
console.log('writeLargeData', buffer.byteLength, 'bytes in',MAX_DATA_SEND_SIZE, 'byte chunks.');
var chunkCount = Math.ceil(buffer.byteLength / MAX_DATA_SEND_SIZE);
var chunkTotal = chunkCount;
var index = 0;
var startTime = new Date();
var transferComplete = function () {
console.log("Transfer Complete");
}
var sendChunk = function () {
if (!chunkCount) {
transferComplete();
return; // so we don't send an empty buffer
}
console.log('Sending data chunk', chunkCount + '.');
var chunk = buffer.slice(index, index + MAX_DATA_SEND_SIZE);
index += MAX_DATA_SEND_SIZE;
chunkCount--;
ble.write(
device_id,
service_uuid,
characteristic_uuid,
chunk,
sendChunk, // success callback - call sendChunk() (recursive)
function(reason) { // error callback
console.log('Write failed ' + reason);
}
)
}
// send the first chunk
sendChunk();
}
Still this would mean for us that we would have to launch about 25k transmissions which I assume will take a long time to complete. Now I wonder why is that the data transmission via Bluetooth is that handicapped.

If you want to try out L2CAP your could modify your Central desktop app somehow like this:
private let characteristicUUID = CBUUID(string: CBUUIDL2CAPPSMCharacteristicString)
...
Then advertize and publish a L2CAP channel:
let service = CBMutableService(type: peripheralUUID, primary: true)
let properties: CBCharacteristicProperties = [.read, .indicate]
let permissions: CBAttributePermissions = [.readable]
let characteristic = CBMutableCharacteristic(type: characteristicUUID, properties: properties, value: nil, permissions: permissions)
self.characteristic = characteristic
service.characteristics = [characteristic]
self.manager.add(service)
self.manager.publishL2CAPChannel(withEncryption: false)
let data = [CBAdvertisementDataLocalNameKey : "Peripherial-42", CBAdvertisementDataServiceUUIDsKey: [peripheralUUID]] as [String : Any]
self.manager.startAdvertising(data)
In your
func peripheralManager(_ peripheral: CBPeripheralManager, central: CBCentral, didSubscribeTo characteristic: CBCharacteristic) {
respective your
func peripheralManager(_ peripheral: CBPeripheralManager, didPublishL2CAPChannel PSM: CBL2CAPPSM, error: Error?) {
offer the PSM value (= kind of socket handle (UInt16), for Bluetooth stream connections):
let data = withUnsafeBytes(of: PSM) { Data($0) }
if let characteristic = self.characteristic {
characteristic.value = data
self.manager.updateValue(data, for: characteristic, onSubscribedCentrals: self.subscribedCentrals)
}
finally in
func peripheralManager(_ peripheral: CBPeripheralManager, didOpen channel: CBL2CAPChannel?, error: Error?)
open an input stream:
channel.inputStream.delegate = self
channel.inputStream.schedule(in: RunLoop.current, forMode: .default)
channel.inputStream.open()
where the delegate could look something like this:
func stream(_ aStream: Stream, handle eventCode: Stream.Event) {
switch eventCode {
case Stream.Event.hasBytesAvailable:
if let stream = aStream as? InputStream {
...
//buffer is some UnsafeMutablePointer<UInt8>
let read = stream.read(buffer, maxLength: capacity)
print("\(read) bytes read")
}
case ...
}
iOS app with Central Role
Assuming you have something like that in your iOS code:
func sendImage(imageData: Data) {
self.manager = CBCentralManager(delegate: self, queue: nil)
self.imageData = imageData
self.bytesToWrite = imageData.count
NSLog("start")
}
then you can modify your peripheral on your iOS client to work with the L2Cap channel like this:
func peripheral(_ peripheral: CBPeripheral, didUpdateValueFor characteristic: CBCharacteristic, error: Error?) {
...
if let characteristicValue = characteristic.value {
let psm = characteristicValue.withUnsafeBytes {
$0.load(as: UInt16.self)
}
print("using psm \(psm) for l2cap channel!")
peripheral.openL2CAPChannel(psm)
}
}
and as soon as you are notified of the opened channel, open the output stream on it:
func peripheral(_ peripheral: CBPeripheral, didOpen channel: CBL2CAPChannel?, error: Error?)
...
channel.outputStream.delegate = self.streamDelegate
channel.outputStream.schedule(in: RunLoop.current, forMode: .default)
channel.outputStream.open()
Your supplied stream delegate might look like this:
func stream(_ aStream: Stream, handle eventCode: Stream.Event) {
switch eventCode {
case Stream.Event.hasSpaceAvailable:
if let stream = aStream as? OutputStream, let imageData = self.imageData {
if self.bytesToWrite > 0 {
let bytesWritten = imageData.withUnsafeBytes {
stream.write(
$0.advanced(by: totalBytes),
maxLength: self.bytesToWrite
)
}
self.bytesToWrite -= bytesWritten
self.totalBytes += bytesWritten
print("\(bytesWritten) bytes written, \(bytesToWrite) remain")
} else {
NSLog("finished")
}
}
case ...
There is a cool WWDC video from 2017, What's New in Core Bluetooth, see here https://developer.apple.com/videos/play/wwdc2017/712/
At around 14:45 it starts to discuss how L2Cap channels are working.
At 28:47, the Get the Most out of Core Bluetooth topic starts, in which performance-related things are discussed in detail. That's probably exactly what you're interested in.
Finally, at 37:59 you will see various possible throughputs in kbps.
Based on the data shown on the slide, the maximum possible speed with L2CAP + EDL (Extended Data Length) + 15ms interval is 394 kbps.

Please have a look at this comment
The following snippet is taken from there
ble.requestMtu(yourDeviceId, 512, () => {
console.log('MTU Size ok.');
}, error => {
console.log('MTU Size failed.');
});
It is suggesting that you need to request the Mtu after connection and then I think you can break your message into chunks of 512 bytes rather than 20 bytes.
They have done this for android specific issue

First I should say that there are already tons of blog posts and Q&As on the exact same topic, so please read them first.
If you run iPhone 7, you have the LE Data Length Extension. The default MTU is also 185 bytes, which means you can send notifications or write without response commands with 182 bytes of payload. And please make sure you absolutely not use Write With Response or Indications since that will almost stall the transfer. When you run iOS in central mode you are restricted to 30 ms connection interval. Using a shorter connection interval can have benefits, so I would suggest you to run iOS in peripheral mode instead so you from the central side can set a connection interval of something short, say 12 ms. Since iPhone X and iPhone 8, you can also switch to the 2MBit/s PHY to get increased transfer speed. So to answer your actual question why BLE data transfer is handicapped: it's not, at least if you follow best practice.
You also haven't told anything about the system that runs your desktop application. If it supports 2 MBit/s PHY, LE Data Length Extension and a MTU of at least 185, then you should be happy and make sure your connections use all those features. If not, you should still get higher performance if you enable at least one of them.

example of AlwaysOnHotwordDetector in Android

Can someone provide an example of how to use the new AlwaysOnHotwordDetector class in Android?
I'd like to build an app, that when the app is running in the background, can detect a hotword like "next", or "back", or "pause".

Unless I have a huge blind spot, I don't think third-party applications can make use of this API. Its strange that AlwaysOnHotwordDetector (and related classes VoiceInteractionService etc.) have been granted public access.
If you are building a privileged app, look through these test projects from AOSP:
Voice Interaction - Basic AlwaysOnHotwordDetector usage/implementation
http://androidxref.com/5.0.0_r2/xref/frameworks/base/tests/VoiceInteraction/
Voice Enrollment - http://androidxref.com/5.0.0_r2/xref/frameworks/base/tests/VoiceEnrollment/
While trying to make this work, I came upon this:
AlwaysOnHotwordDetector's constructor:
/**
* #param text The keyphrase text to get the detector for.
* #param locale The java locale for the detector.
* #param callback A non-null Callback for receiving the recognition events.
* #param voiceInteractionService The current voice interaction service.
* #param modelManagementService A service that allows management of sound models.
*
* #hide
*/
public AlwaysOnHotwordDetector(String text, Locale locale, Callback callback,
KeyphraseEnrollmentInfo keyphraseEnrollmentInfo,
IVoiceInteractionService voiceInteractionService,
IVoiceInteractionManagerService modelManagementService) {
mText = text;
mLocale = locale;
mKeyphraseEnrollmentInfo = keyphraseEnrollmentInfo;
mKeyphraseMetadata = mKeyphraseEnrollmentInfo.getKeyphraseMetadata(text, locale);
mExternalCallback = callback;
mHandler = new MyHandler();
mInternalCallback = new SoundTriggerListener(mHandler);
mVoiceInteractionService = voiceInteractionService;
mModelManagementService = modelManagementService;
new RefreshAvailabiltyTask().execute();
}
The statement of interest here is:
mKeyphraseMetadata = mKeyphraseEnrollmentInfo.getKeyphraseMetadata(text, locale);
What does KeyphraseEnrollmentInfo#getKeyphraseMetadata(String, Locale) do?
/**
* Gets the {#link KeyphraseMetadata} for the given keyphrase and locale, null if any metadata
* isn't available for the given combination.
*
* #param keyphrase The keyphrase that the user needs to be enrolled to.
* #param locale The locale for which the enrollment needs to be performed.
* This is a Java locale, for example "en_US".
* #return The metadata, if the enrollment client supports the given keyphrase
* and locale, null otherwise.
*/
public KeyphraseMetadata getKeyphraseMetadata(String keyphrase, Locale locale) {
if (mKeyphrases == null || mKeyphrases.length == 0) {
Slog.w(TAG, "Enrollment application doesn't support keyphrases");
return null;
}
for (KeyphraseMetadata keyphraseMetadata : mKeyphrases) {
// Check if the given keyphrase is supported in the locale provided by
// the enrollment application.
if (keyphraseMetadata.supportsPhrase(keyphrase)
&& keyphraseMetadata.supportsLocale(locale)) {
return keyphraseMetadata;
}
}
Slog.w(TAG, "Enrollment application doesn't support the given keyphrase/locale");
return null;
}
At this point, my example project kept telling me: Enrollment application doesn't support keyphrases. So, digging a bit further - to support keyphrases, we need to provide additional meta-data:
// Taken from class KeyphraseEnrollmentInfo
/**
* Name under which a Hotword enrollment component publishes information about itself.
* This meta-data should reference an XML resource containing a
* <code><{#link
* android.R.styleable#VoiceEnrollmentApplication
* voice-enrollment-application}></code> tag.
*/
private static final String VOICE_KEYPHRASE_META_DATA = "android.voice_enrollment";
Additionally, we will need the android.permission.MANAGE_VOICE_KEYPHRASES permission. This is where the example project gets stuck:
<!-- Must be required by hotword enrollment application,
to ensure that only the system can interact with it.
#hide <p>Not for use by third-party applications.</p> -->
<permission android:name="android.permission.MANAGE_VOICE_KEYPHRASES"
android:label="#string/permlab_manageVoiceKeyphrases"
android:description="#string/permdesc_manageVoiceKeyphrases"
android:protectionLevel="signature|system" />
The permission required to support hotword detection is not available to third-party applications. I still can't figure out why package android.service.voice package has public access. Perhaps I am missing something here.

Add ambient light sensor into cordova-2.5.0.js - phonegap

I have to develop an Android application using phongap that retrieves the sensors data from the device.
One of the sensors I have to listen to is the ambient light sensor. This sensor has no implementation in phoneGap, so I have to add it as a plugin to PhoneGap.
I know how to add plugin and I know how to access the ALS data from Java - but in order to be sure that I am implementing it well I want to implement it as PhoneGap implements other sensors like Accelerometer. Therefor I wrote a ALSManager class in java that I implemented as I found the Accelerometer was implemented here:
https://github.com/apache/cordova-android/blob/master/framework/src/org/apache/cordova/AccelListener.java
and added lightSensor and lightValues modules like the acceleromter and acceleration modules.
But when I run this application I got following error message:
TypeError: Object # has no method 'getCurrentLight'
(and in the lightSensor module I have getCurrentLight method).
does any one can please suggest me what I am missing? or what do I have to do?
Thanks in advance,
The code I added in the cordova-2.5.0.js. Let me know if it's not enough:
// file: lib/common/plugin/LightValues.js
define("cordova/plugin/LightValues", function(require, exports, module) {
var Acceleration = function(lux, timestamp) {
this.lux = lux;
this.timestamp = timestamp || (new Date()).getTime();
};
module.exports = LightValues;
});
// file: lib/common/plugin/lightSensor.js
define("cordova/plugin/lightSensor", function(require, exports, module) {
/**
* This class provides access to device accelerometer data.
* #constructor
*/
var argscheck = require('cordova/argscheck'),
utils = require("cordova/utils"),
exec = require("cordova/exec"),
LightValues = require('cordova/plugin/LightValues');
// Is the accel sensor running?
var running = false;
// Keeps reference to watchAcceleration calls.
var timers = {};
// Array of listeners; used to keep track of when we should call start and stop.
var listeners = [];
// Last returned acceleration object from native
var light = null;
// Tells native to start.
function start() {
exec(function(a) {
var tempListeners = listeners.slice(0);
light = new LightValues(a.lux, a.timestamp);
for (var i = 0, l = tempListeners.length; i < l; i++) {
tempListeners[i].win(light);
}
}, function(e) {
var tempListeners = listeners.slice(0);
for (var i = 0, l = tempListeners.length; i < l; i++) {
tempListeners[i].fail(e);
}
}, "Light", "start", []);
running = true;
}
// Tells native to stop.
function stop() {
exec(null, null, "Light", "stop", []);
running = false;
}
// Adds a callback pair to the listeners array
function createCallbackPair(win, fail) {
return {win:win, fail:fail};
}
// Removes a win/fail listener pair from the listeners array
function removeListeners(l) {
var idx = listeners.indexOf(l);
if (idx > -1) {
listeners.splice(idx, 1);
if (listeners.length === 0) {
stop();
}
}
}
var lightSensor = {
/**
* Asynchronously acquires the current acceleration.
*
* #param {Function} successCallback The function to call when the acceleration data is available
* #param {Function} errorCallback The function to call when there is an error getting the acceleration data. (OPTIONAL)
* #param {AccelerationOptions} options The options for getting the accelerometer data such as timeout. (OPTIONAL)
*/
getCurrentLight: function(successCallback, errorCallback, options) {
//argscheck.checkArgs('fFO', 'lightSensor.getCurrentLight', arguments);
var p;
var win = function(a) {
removeListeners(p);
successCallback(a);
};
var fail = function(e) {
removeListeners(p);
errorCallback && errorCallback(e);
};
p = createCallbackPair(win, fail);
listeners.push(p);
if (!running) {
start();
}
},
/**
* Asynchronously acquires the acceleration repeatedly at a given interval.
*
* #param {Function} successCallback The function to call each time the acceleration data is available
* #param {Function} errorCallback The function to call when there is an error getting the acceleration data. (OPTIONAL)
* #param {AccelerationOptions} options The options for getting the accelerometer data such as timeout. (OPTIONAL)
* #return String The watch id that must be passed to #clearWatch to stop watching.
*/
watchLight: function(successCallback, errorCallback, options) {
//argscheck.checkArgs('fFO', 'lightSensor.watchLight', arguments);
// Default interval (10 sec)
var frequency = (options && options.frequency && typeof options.frequency == 'number') ? options.frequency : 10000;
// Keep reference to watch id, and report accel readings as often as defined in frequency
var id = utils.createUUID();
var p = createCallbackPair(function(){}, function(e) {
removeListeners(p);
errorCallback && errorCallback(e);
});
listeners.push(p);
timers[id] = {
timer:window.setInterval(function() {
if (light) {
successCallback(light);
}
}, frequency),
listeners:p
};
if (running) {
// If we're already running then immediately invoke the success callback
// but only if we have retrieved a value, sample code does not check for null ...
if (light) {
successCallback(light);
}
} else {
start();
}
return id;
},
/**
* Clears the specified accelerometer watch.
*
* #param {String} id The id of the watch returned from #watchAcceleration.
*/
clearWatch: function(id) {
// Stop javascript timer & remove from timer list
if (id && timers[id]) {
window.clearInterval(timers[id].timer);
removeListeners(timers[id].listeners);
delete timers[id];
}
}
};
module.exports = lightSensor;
});

I think maybe the problem is that you are adding your plugin code to cordova-2.5.0.js file. Instead what you should do is create a standalone JS file for each of your JavaScript files and then cordova.require() those files in the HTML page where you want to use that functionality.
So, create LightValues.js and LightSensor.js as separate files somewhere in your www folder. Then in your HTML file, make sure to include the JS file: <script type="text/javascript" src="path-to-lightSensor.JS-file"> (You'd only need to include this one file since it require()s the second one.)
Next, in deviceReady() function, you can call the light sensor with var lightSensor = cordova.require("cordova/plugin/lightSensor"). Notice that the cordova/plugin/lightSensor is not the path to the JS file but the name of it module that you declared in the define() section when you wrote the plugin.
After this you should be able to call lightSensor.getCurrentLight(). If you console.log(lightSensor) you would expect to see all of the available methods that you wrote.
Note that I'm not positive that cordova.require and cordova.define work in cordova-2.5. I'd hope that they do but this page sort of suggests it may not be supported until 2.6. If you are having problems after splitting the files out, maybe it is because of this.

I have just developed a light sensor plugin and fortunately succeed. I have just read the code above and found some small mistakes about identifier e.g "var Acceleration = function(lux, timestamp)" the variable should be LightValues instead of Acceleration. So please check the code first to void some essential mistakes. Then, I first use "lux" as the name of the variable but I got an undefined value of light when debugging the program. So I change "lux" into "x" and it did work!
There are 6 files should be paid attention to: the "LightListener.java", "LightValues.js", "LightSensor.js","cordova_plugin.js", "index.html" and "config.xml". If you configure all the 6 files, the program should work.