I have developed an Android App which runs on both a smartphone and a smartwatch in parallel. On both devices, (let's say) it reads certain sensor data, processes that data (calculate its mean), and then store that results. The watch sends this result to the phone so all storing takes place on the phone. I used buffer writer to write a number into a text file every 5 seconds.
Now after every 320 data items exchanges from watch to the phone, my app on the phone gets killed and I get "the name of the app" is unfortunately stopped as a message. I can't figure it what why they stop exactly after this time? The app running on the watch continues to work fine. However, I cannot store its data because it cannot communicate to the phone version so I get this message "the app is unfortunately stopped as a message" every time the watch sends a number to phone for storing. The app has one activity which has a service (foreground).
Could it be that there is a limit on the amount of data being shared?
The code on watch:
// Create a data map and put data in it
private void increaseCounter() {
PutDataMapRequest putDataMapReq = PutDataMapRequest.create("/count");
putDataMapReq.getDataMap().putInt(COUNT_KEY, count++); // I add current time here as well
PutDataRequest putDataReq = putDataMapReq.asPutDataRequest();
PendingResult<DataApi.DataItemResult> pendingResult =
Wearable.DataApi.putDataItem(mGoogleApiClient, putDataReq);
}
Code on phone (possible problematic area):
#Override
public void onDataChanged(DataEventBuffer dataEvents) {
for (DataEvent event : dataEvents) {
if (event.getType() == DataEvent.TYPE_CHANGED) {
// DataItem changed
DataItem item = event.getDataItem();
if (item.getUri().getPath().compareTo("/count") == 0) {
DataMap dataMap = DataMapItem.fromDataItem(item).getDataMap();
updateCount(dataMap.getInt(COUNT_KEY));
}
} else if (event.getType() == DataEvent.TYPE_DELETED) {
// DataItem deleted
}
}
}
You have to use Service with StartForeground notification to be sure app is always working.
and try to use START_STICKY flag while staring.
UPDATE
You have to dealloc memory of dataevent:
#Override
public void onDataChanged(DataEventBuffer dataEvents) {
try{
for(DataEvent dataEvent: dataEvents){
if(dataEvent.getType() != DataEvent.TYPE_CHANGED){
continue;
}
////... code
dataEvents.release();
}catch (Exception e){
Log.v("SunshineWatchFace",e.getMessage());
}
}
Related
I am currently trying to communicate with a Zebra printer via a react-native application, on mobile I am trying to send my ZPL code (instructions for the printer to print the content i want) from my application to the printer via PrintConnect, Zebra also provides a pdf file guiding people on how to communicate to the app via intents available here however the examples dislpayed on the guide are using a different language.
My question then is how would i go about replicating this (Page 96, Passthrough Intent example) :
Intent intent = new Intent();
intent.setComponent(new ComponentName("com.zebra.printconnect",
"com.zebra.printconnect.print.PassthroughService"));
intent.putExtra("com.zebra.printconnect.PrintService.PASSTHROUGH_DATA", passthroughBytes);
intent.putExtra("com.zebra.printconnect.PrintService.RESULT_RECEIVER", buildIPCSafeReceiver(new
ResultReceiver(null) {
#Override
protected void onReceiveResult(int resultCode, Bundle resultData) {
if (resultCode == 0) { // Result code 0 indicates success
// Handle successful print
} else {
// Handle unsuccessful print
// Error message (null on successful print)
String errorMessage = resultData.getString("com.zebra.printconnect.PrintService.ERROR_MESSAGE");
}
}
}));
Into something acceptable by the react-native-send-intent package such as this:
SendIntentAndroid.openApp("com.mycorp.myapp", {
"com.mycorp.myapp.reason": "just because",
"com.mycorp.myapp.data": "must be a string",
}).then(wasOpened => {});
Thank you for the time you took to read my question.
I am running into a issue that is the opposite problem of this thread:
AltBeacon not detect beacon when app is closed
I have an app that uses altbeacon (http://altbeacon.org/)
The app initializes the alt-beacon implementing the interfaces at the application level as below (details omitted)
public class MyApp extends Application implements
BootstrapNotifier,
BeaconConsumer {
//some code
#Override
public void onCreate() {
super.onCreate();
initBeacons();
}
public void initBeacons() {
mBackgroundPowerSaver = new BackgroundPowerSaver(this);
org.altbeacon.beacon.BeaconManager altBeaconManager = org.altbeacon.beacon.BeaconManager.getInstanceForApplication(this);
altBeaconManager.getBeaconParsers().add(new BeaconParser().setBeaconLayout("m:2-3=0215,i:4-19,i:20-21,i:22-23,p:24-24"));
// estimote
altBeaconManager.setBackgroundScanPeriod(5000);
altBeaconManager.setBackgroundBetweenScanPeriod(25000);
mBeaconManager = MyBeaconManager.getInstance(this, altBeaconManager);
mRegionBootstrap = new RegionBootstrap(this, MyBeaconManager.getRegions());
altBeaconManager.bind(this);
}
#Override
public void onBeaconServiceConnect() {
Thread thread = new Thread() {
public void run() {
// Try range the beacons
rangeMyBeacons();
}
};
thread.start();
}
#Override
public void didEnterRegion(Region region) {
// Some code
}
#Override
public void didExitRegion(Region region) {
// Some code
}
#Override
public void didDetermineStateForRegion(int i, Region region) {
// Some code
}
public class MyBeaconManager implements
RangeNotifier {
// some code
However, If I kill the app or restart the phone, without any special broadcasts or app permissions the alt-beacon service comes back alive. Alt-beacon re-starts itself all the time, in other words. Notice that I don't have any foreground services running. Here' is a screenshot of the app after several hours (and I rebooted the phone), with all apps closed. You can see the alt-beacon is alive and scanning the beacons.
yet when I look at alt-beacon code, it is not a foreground service
#Override
public int onStartCommand(Intent intent, int flags, int startId) {
LogManager.i(TAG,
intent == null ?
"starting with null intent"
:
"starting with intent " + intent.toString()
);
return super.onStartCommand(intent, flags, startId);
}
I did search inside the library and I see not hits to START_REDELIVER_INTENT or START_STICKY.
My question is how does alt-beacon keep the service alive when the app is killed?
The reason I want to understand this feature is that I am writing a similar service but I can only get it do work as alt-beacon if I wrap it into a foreground service. Everything else I tried, the service gets killed as soon as the app closes.
thank you.
The Android Beacon Library uses an AlarmManager to keep the scanning service running in the background. It periodically sets an alarm for 5 minutes in the future, which causes the operating system to deliver it a BroadcastIntent which will start the scanning service if stopped. When running, the library continually reschedules this alarm.
You can see the code that does that here:
https://github.com/AltBeacon/android-beacon-library/blob/master/src/main/java/org/altbeacon/beacon/service/scanner/CycledLeScanner.java#L339
// In case we go into deep sleep, we will set up a wakeup alarm when in the background to kickoff
// off the scan cycle again
protected void setWakeUpAlarm() {
// wake up time will be the maximum of 5 minutes, the scan period, the between scan period
long milliseconds = 1000l * 60 * 5; /* five minutes */
if (milliseconds < mBetweenScanPeriod) {
milliseconds = mBetweenScanPeriod;
}
if (milliseconds < mScanPeriod) {
milliseconds = mScanPeriod;
}
AlarmManager alarmManager = (AlarmManager) mContext.getSystemService(Context.ALARM_SERVICE);
alarmManager.set(AlarmManager.ELAPSED_REALTIME_WAKEUP, SystemClock.elapsedRealtime() + milliseconds, getWakeUpOperation());
LogManager.d(TAG, "Set a wakeup alarm to go off in %s ms: %s", milliseconds, getWakeUpOperation());
}
This design ensures that if the app needs to be terminated due to low memory, scanning will be restarted five minutes in the future. This allows the phone time to complete the memory intensive operation, while still allowing beacon detections in a reasonable time frame.
I have an older implementation using NAudio 1.6 to play a ring tone signalling an incoming call in an application. As soon as the user acceptes the call, I stop the playback.
Basically the follwing is done:
1. As soon as the I get an event that a call must be signalled, a timer is started
2. Inside this timer Play() on the player
3. When the timer starts again, a check is performed if the file is played by checking the CurrentTime property against the TotalTime propery of the WaveStream
4. When the user accepts the call, Stop() is called on the player and also stop the timer
The point is, that we run sometimes in cases where the playback is still repeated although the timer is stopped and the Stop() was called on the player.
In the following link I read that the classes BufferedWaveProvider and WaveChannel32 which are used in the code are always padding the buffer with zero.
http://mark-dot-net.blogspot.com/2011/05/naudio-and-playbackstopped-problem.html
Is it possible that the non-stopping playback is due to usage of the classes BufferedWaveProvider and WaveChannel32?
In NAudio 1.7 the AudioFileReader class is there. Is this class also padding with zeros? I did not find a property like PadWithZeroes in this class. Does it make to use AudioFileReader in this case of looped playback?
Below the code of the current implementation of the TimerElapsed
void TimerElapsed(object sender, ElapsedEventArgs e)
{
try
{
WaveStream stream = _audioStream as WaveStream;
if (stream != null && stream.CurrentTime >= stream.TotalTime )
{
StartPlayback();
}
}
catch (Exception ex)
{
//do some actions here
}
}
The following code creates the input stream:
private WaveStream CreateWavInputStream(string path)
{
WaveStream readerStream = new WaveFileReader(path);
if (readerStream.WaveFormat.Encoding != WaveFormatEncoding.Pcm)
{
readerStream = WaveFormatConversionStream.CreatePcmStream(readerStream);
readerStream = new BlockAlignReductionStream(readerStream);
}
if (readerStream.WaveFormat.BitsPerSample != 16)
{
var format = new WaveFormat(readerStream.WaveFormat.SampleRate, 16, readerStream.WaveFormat.Channels);
readerStream = new WaveFormatConversionStream(format, readerStream);
}
WaveChannel32 inputStream = new WaveChannel32(readerStream);
return inputStream;
}
I want to use CMSensorRecorder to continuously collect the Accelerometer data, also if user didn't open my app on watch\phone.
What I want to do is - "whenever possible" (i.e. watch is awake and I can execute code), do the following:
call recordAccelerometerForDuration to tell watch to keep collecting data for as long as possible
call accelerometerDataFromDate to get data collected so far (or from last time I got the data)
My question is - how to implement the "whenever possible", i.e. how can I cause my watch application to wake up and execute these apis whenever the watch itself wakes up ?
CMSensorRecorder- to recored data continuously use ExtentionDelegate to triger CMSensorRecorder to invoke start recording and reading data.
func applicationDidBecomeActive() {
print("Active")
// Restart any tasks that were paused (or not yet started) while the application was inactive. If the application was previously in the background, optionally refresh the user interface.
AccelorometerDataReader.sharedReader.sessionEndDate = Date()
AccelorometerDataReader.sharedReader.getRecordedData()
}
func applicationWillResignActive() {
// Sent when the application is about to move from active to inactive state. This can occur for certain types of temporary interruptions (such as an incoming phone call or SMS message) or when the user quits the application and it begins the transition to the background state.
// Use this method to pause ongoing tasks, disable timers, etc.
print("inactive")
AccelorometerDataReader.sharedReader.startReadingAccelorometerData()
AccelorometerDataReader.sharedReader.sessionStartDate = Date()
}
//AccelorometerReaderCode
func startReadingAccelorometerData()
{
if CMSensorRecorder.isAccelerometerRecordingAvailable()
{
if CMSensorRecorder.isAuthorizedForRecording()
{
print("Authorized.......")
DispatchQueue.global(qos: .background).async
{
self.recorder?.recordAccelerometer(forDuration: 3 * 60) // Record for 3 minutes
}
}
else
{
print("not authorized")
}
}
else
{
print("NOt available for recording")
}
}
func getRecordedData()
{
DispatchQueue.global(qos: .background).async
{
if self.sessionStartDate < self.sessionEndDate
{
if let list = self.recorder?.accelerometerData(from: self.sessionStartDate, to:self.sessionEndDate)
{
for record in list
{
let data = record as! CMRecordedAccelerometerData
print("x: \(data.acceleration.x) y: \(data.acceleration.y) z: \(data.acceleration.z) time :\(data.startDate.getFormattedDate())")
}
}
}
}
}
}
It doesn't seem you can. I have tried the following but none of these really work.
Register for backgroundApplicationRefresh (watchOS 3) and make sure the app is saved to the Dock. Dock apps can rely on getting one call an hour to update themselves.
On completion of the period query for the accelerometer data and archive the result to file and then transfer the file to the iOS companion app. The file transfer will occur in the background independent of the watch kit app assuming you get enough CPU time to write the accelerometer data to file.
Try using ProcessInfo API to keep the process running.
To date the only success I have had is in running an async thread to extract the data and keeping the watch kit app active by tapping on the screen each time the screen blanks.
Hope this helps and please post any better solution you find.
I have to launch the app on receiving notification. The following piece of code works fine when the app is killed and notification is received (i.e the code inside if condition). But when the app is running in foreground or background, multiple instances of the activity gets created(i.e snippet in else condition). It's not the MainActivity that has to be launched on receiving the notification, instead it's some other activity containing the broadcast Receiver.
I have added the following lines in the onMessage of GCMintentService class.
if (currentPackage.equalsIgnoreCase(context.getPackageName()
.toString())) {
broadcastMessage(context, message);
} else {
Intent mIntent = new Intent(context, MainActivity.class);
mIntent.setAction(Intent.ACTION_MAIN);
mIntent.addCategory(Intent.CATEGORY_LAUNCHER);
mIntent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
context.startActivity(mIntent);
}
In the activity, under onReceive method of BroadcastReceiver, i am starting the activity again.
private final BroadcastReceiver mHandleMessageReceiver = new BroadcastReceiver() {
#Override
public void onReceive(Context context, Intent intent) {
startActivity(getIntent().setFlags(Intent.FLAG_ACTIVITY_REORDER_TO_FRONT));
}
};
I also had this requirement in one of my application. We can achieve it if we call
Intent mIntent = new Intent(context, MainActivity.class);
mIntent.setAction(Intent.ACTION_MAIN);
mIntent.addCategory(Intent.CATEGORY_LAUNCHER);
mIntent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
context.startActivity(mIntent);
broadcastMessage(context, message);
In the main activity use the following in the broadcast receiver that would receive the broadcasted message above.
WakeLock wakeLock = null;
KeyguardManager kgMgr = (KeyguardManager) getSystemService(Context.KEYGUARD_SERVICE);
boolean locked = kgMgr.inKeyguardRestrictedInputMode();
PowerManager pm = (PowerManager) context
.getSystemService(Context.POWER_SERVICE);
if (!pm.isScreenOn()) {
wakeLock = pm.newWakeLock(PowerManager.FULL_WAKE_LOCK
| PowerManager.ACQUIRE_CAUSES_WAKEUP, "MyWakeLock");
wakeLock.acquire();
}
if (locked) {
Window mWindow = getWindow();
mWindow.addFlags(WindowManager.LayoutParams.FLAG_SHOW_WHEN_LOCKED);
mWindow.addFlags(WindowManager.LayoutParams.FLAG_TURN_SCREEN_ON);
}
Personally I feel that this is not the best of the answers and also best of the ideas to open the app directly when received a notification as there will be many functions like onCreate onResume, will be triggered automatically, spoil the users work if they are in a really important work by opening another app directly, also we need to put a lot of flags or use any other method to manage the flow of the application, when user open the app, app comes from background, app opened due notification and all such cases. Avoid it as it spoils the whole user experience.