I've been working on an app where I need to get the location of the device. The thing is, I want to try at least 5 or 10 times and I want a delay in between each try, in order to show a error message in the screen after each try (FailedLocationMSG). The reason why I want this delay is because some times it takes some time to the gps start working and get the actual location. I've tried so many things and I can't make it work. The idea is to have an interface similar to a 'terminal' where I will display a message (Error, trying again 1/5.. Error 2/5....) after each try. The problem is, I've tried using Handler and Thread.sleep but I always get my screen locked and I can't see the error message displayed on the screen after each try.
This is the method where I get the location:
int breakloop=0;
private void GetLocation(){
locationmanager=(LocationManager)getSystemService(Context.LOCATION_SERVICE);
Criteria cri=new Criteria();
String provider=locationmanager.getBestProvider(cri,false);
if(provider!=null & !provider.equals("")){
//Get location
final Location location=locationmanager.getLastKnownLocation(provider);
locationmanager.requestLocationUpdates(provider,2000,10,this);
while(breakloop<10){
breakloop++;
if(location!=null)
onLocationChanged(location);
else
FailedLocationMSG(breakloop);
}
}else
Toast.makeText(getApplicationContext(),"Provider is null",Toast.LENGTH_LONG).show();
}
You could use a FutureTask and a Callable for your location check and wait for its return value.
public class LocationChecker implements Callable<Location> {
#Override
public Location call() throws Exception {
//do your stuff for location check
return location;
}
}
in your method you do something like
LocationChecker lc = new LocationChecker();
FutureTask<Location> ft = new FutureTask<Location>(lc);
ExecutorService es = Executors.newCachedThreadPool();
es.execute(ft);
Location loc;
int attempts = 0;
while(attempts < 10) {
if(ft.isDone() && loc != null) {
es.shutdown();
break;
}
else if(ft.isDone() && loc == null) {
ft = new FutureTask<Location>(lc);
es.execute(ft);
attempts++;
}
loc = ft.get();
}
This will check your location and will wait for the result (ten times).
Related
I'm working on a sketch that is receiving network events from an external program (specifically, an OpenFrameworks sketch), using the processing.net library.
Inside the draw method, I have the following code to parse the incoming data, and assign it appropriately to display a value of text in a text label:
void draw()
{
// check for incoming data
Client client = server.available();
if (client != null) {
// check for a full line of incoming data
String line = client.readStringUntil('\n');
if (line != null) {
//println(line);
int val = int(trim(line)); // extract the predicted class
//println(val);
if (val == 1) {
messageText = "EVENT 1";
} else if (val == 2) {
messageText = "EVENT 2";
} else if (val == 3) {
messageText = "EVENT 3";
}
}
}
// draw
background(0);
textFont(f,64);
fill(255);
textAlign(CENTER);
text(messageText, width/2, height/2);
}
Through logging, I have verified that the data is being received properly
However, I'm experiencing a very annoying bug - the text of my messageText label is VERY slow to update...after a new event has occurred (and is shown as such through logging), the messageText will still display the value of the last event for several seconds.
Anyone have any pointers on how to speed up performance here?
Thanks!
EDIT: Below is the full, complete sketch code:
import processing.net.*; // include the networking library
Server server; // will receive predictions
String messageText;
PFont f;
void setup()
{
fullScreen();
//size(200,200);
server = new Server(this, 5204); // listen on port 5204
messageText = "NO HAND";
f = createFont("Arial",16,true); // Arial, 16 point, anti-aliasing on
}
void draw()
{
// check for incoming data
Client client = server.available();
if (client != null) {
// check for a full line of incoming data
String line = client.readStringUntil('\n');
if (line != null) {
//println(line);
int val = int(trim(line)); // extract the predicted class
//println(val);
if (val == 1) {
messageText = "EVENT 1";
} else if (val == 2) {
messageText = "EVENT 2";
} else if (val == 3) {
messageText = "EVENT 3";
}
}
}
// draw
background(0);
textFont(f,64);
fill(255);
textAlign(CENTER);
text(messageText, width/2, height/2);
}
EDIT2 As Kevin pointed out below, my solution is rather hacky. I'm attempting to use the Message Events methods from the Networking library, rather than stuffing all my networking code inside of the draw() method.
So, I tried implementing the clientEvent method as such. However, I think I may be misunderstanding something...even though my original, hacky code seems to work OK now, my new code below using this delegate method doesn't seem to work at all. Basically, I have to run my sketch first, which creates a server, that my external program connects to. That program then sends out data that's received by my Processing sketch.
Here's what my full sketch looks like - anyone know where my misunderstanding may be coming from?
import processing.net.*; // include the networking library
Server server; // will receive predictions
Client client;
String messageText;
int dataIn;
PFont f;
void setup() {
fullScreen(P3D);
frameRate(600);
server = new Server(this, 5204); // listen on port 5204
client = server.available();
messageText = "NO HAND";
textAlign(CENTER);
fill(255);
f = createFont("Arial",48,true); // Arial, 16 point, anti-aliasing on
textFont(f, 120);
}
void draw() {
// draw
background(0);
text(messageText, width/2, height/2);
}
// If there is information available to read
// this event will be triggered
void clientEvent(Client client) {
String msg = client.readStringUntil('\n');
// The value of msg will be null until the
// end of the String is reached
if (msg != null) {
int val = int(trim(line)); // extract the predicted class
println(val);
if (val == 1) {
messageText = "A";
} else if (val == 2) {
messageText = "B";
} else if (val == 3) {
messageText = "C";
} else if (val == 4) {
messageText = "D";
}
}
}
}
So, the answer ended up having to do with the framerate and renderer used in the project. Since the network update code was being called in my sketch's draw method, the speed at which it was called was dependent on the framerate/renderer used.
After a bit of experimentation / trial-and-error, changing the sketch to use the FX2D renderer, and a framerate of 600, significantly improved performance to the degree at which I needed.
void setup()
{
fullScreen(FX2D);
frameRate(600);
...
}
EDIT:
After a conversation with one of the Processing core team members, I'm considering my networking code correct and complete. Changing the renderer to FX2D significantly improved performance.
In my very specific use case, I'm running the sketch full-screen on a MacBookPro with Retina display. Bumping the framerate value high, and changing the renderer, gave me the performance I required for my quick prototype sketches.
I found the demo code here: https://github.com/googlesamples/android-vision/blob/master/visionSamples/FaceTracker/app/src/main/java/com/google/android/gms/samples/vision/face/facetracker/FaceTrackerActivity.java
and my question is how to take picture when face detected and save it to device, and when we take 1st picture next picture will be take after 5s when face detected because we can't save to many picture to device.
You have to add FaceDetectionListener in camera API then call startFaceDetection() method,
CameraFaceDetectionListener fDListener = new CameraFaceDetectionListener();
mCamera.setFaceDetectionListener(fDetectionListener);
mCamera.startFaceDetection();
Implement Camera.FaceDetectionListener, you receive the detected face in onFaceDetection override method,
private class MyFaceDetectionListener
implements Camera.FaceDetectionListener {
#Override
public void onFaceDetection(Face[] faces, Camera camera) {
if (faces.length == 0) {
Log.i(TAG, "No faces detected");
} else if (faces.length > 0) {
Log.i(TAG, "Faces Detected = " +
String.valueOf(faces.length));
public List<Rect> faceRects;
faceRects = new ArrayList<Rect>();
for (int i=0; i<faces.length; i++) {
int left = faces[i].rect.left;
int right = faces[i].rect.right;
int top = faces[i].rect.top;
int bottom = faces[i].rect.bottom;
Rect uRect = new Rect(left0, top0, right0, bottom0);
faceRects.add(uRect);
}
// add function to draw rects on view/surface/canvas
}
}
As per your case, new Handler().postDelayed(new Runnable,long seconds) take 2nd picture inside runnable after 5 seconds.
Please let me know if you have any queries.
I've got a problem similar to the question/answer posed here: https://stackoverflow.com/a/22461014. However, the difference is that the I'm trying to decode from the UnityMain thread (Unity's main loop). Calling from Update(), I pass a byte array and a textureId to MediaCodec's decoder.
public void decodeFrameToTexture(BytePointer pixels, int len, int textureID) {
if ( this.textureID != textureID) {
Log.d(TAG, "TextureID changed: " + textureID);
this.textureID = textureID;
SurfaceTexture surfaceTexture = new SurfaceTexture(textureID);
mSurface = new Surface(surfaceTexture);
outputSurface = new CodecOutputSurface(width, height, textureID);
}
... then we do the decoding (basically a copy of the code at http://bigflake.com/mediacodec/ExtractMpegFramesTest.java.txt but without the while loop, as this is frame-by-frame. Also copied the CodecOutputSurface and supporting classes basically verbatim).
Finally we have this code:
decoder.releaseOutputBuffer(decoderStatus, info.size != 0 && outputSurface != null /*render*/);
if ( outputSurface != null ) {
outputSurface.awaitNewImage();
outputSurface.drawImage(true);
}
The trouble is, awaitNewImage() always times out without getting a frame, leading back to the problem referenced here, that the onFrameAvailable() callback is never getting called.
For reference, UnityMain does not have a Looper component. When running this code:
Looper looper;
if ((looper = Looper.myLooper()) != null) {
mEventHandler = new EventHandler(looper);
} else if ((looper = Looper.getMainLooper()) != null) {
mEventHandler = new EventHandler(looper);
} else {
mEventHandler = null;
}
the assigned looper from that thread is the MainLooper looper. Any ideas would be appreciated. As stated by #fadden, "the trick is to make sure that frame-available events arrive on a different thread from the one sitting in awaitNewImage()". Given that we're running
mSurfaceTexture.setOnFrameAvailableListener(this);
from UnityMain, I think this satisfies this requirement? The callback should be called from the "main" thread?
I'm loading local Couchbase instance with application specific json objects.
Relevant code is:
CouchbaseClient getCouchbaseClient()
{
List<URI> uris = new LinkedList<URI>();
uris.add(URI.create("http://localhost:8091/pools"));
CouchbaseConnectionFactoryBuilder cfb = new CouchbaseConnectionFactoryBuilder();
cfb.setFailureMode(FailureMode.Retry);
cfb.setMaxReconnectDelay(1500); // to enqueue an operation
cfb.setOpTimeout(10000); // wait up to 10 seconds for an operation to succeed
cfb.setOpQueueMaxBlockTime(5000); // wait up to 5 seconds when trying to
// enqueue an operation
return new CouchbaseClient(cfb.buildCouchbaseConnection(uris, "my-app-bucket", ""));
}
Method to store entry (I'm using suggestions from Bulk Load and Exponential Backoff):
void continuosSet(CouchbaseClient cache, String key, int exp, Object value, int tries)
{
OperationFuture<Boolean> result = null;
OperationStatus status = null;
int backoffexp = 0;
do
{
if (backoffexp > tries)
{
throw new RuntimeException(MessageFormat.format("Could not perform a set after {0} tries.", tries));
}
result = cache.set(key, exp, value);
try
{
if (result.get())
{
break;
}
else
{
status = result.getStatus();
LOG.warn(MessageFormat.format("Set failed with status \"{0}\" ... retrying.", status.getMessage()));
if (backoffexp > 0)
{
double backoffMillis = Math.pow(2, backoffexp);
backoffMillis = Math.min(1000, backoffMillis); // 1 sec max
Thread.sleep((int) backoffMillis);
LOG.warn("Backing off, tries so far: " + tries);
}
backoffexp++;
}
}
catch (ExecutionException e)
{
LOG.error("ExecutionException while doing set: " + e.getMessage());
}
catch (InterruptedException e)
{
LOG.error("InterruptedException while doing set: " + e.getMessage());
}
}
while (status != null && status.getMessage() != null && status.getMessage().indexOf("Temporary failure") > -1);
}
When continuosSet method called for a large amount of objects to store (single thread) e.g.
CouchbaseClient cache = getCouchbaseClient();
do
{
SerializableData data = queue.poll();
if (data != null)
{
final String key = data.getClass().getSimpleName() + data.getId();
continuosSet(cache, key, 0, gson.toJson(data, data.getClass()), 100);
...
it generates CheckedOperationTimeoutException inside of continuosSet method in result.get() operation.
Caused by: net.spy.memcached.internal.CheckedOperationTimeoutException: Timed out waiting for operation - failing node: 127.0.0.1/127.0.0.1:11210
at net.spy.memcached.internal.OperationFuture.get(OperationFuture.java:160) ~[spymemcached-2.8.12.jar:2.8.12]
at net.spy.memcached.internal.OperationFuture.get(OperationFuture.java:133) ~[spymemcached-2.8.12.jar:2.8.12]
Can someone shed light into this how to overcome and recover from this situation? Is there a good technique/workaround on how to bulk load in Java client for Couchbase? I already explored documentation Performing a Bulk Set which is unfortunately for PHP Couchbase client.
My suspicion is that you may be running this in a JVM spawned from the command line that doesn't have that much memory. If that's the case, you could hit longer GC pauses which could cause the timeout you're mentioning.
I think the best thing to do is to try a couple of things. First, raise the -Xmx argument to the JVM to use more memory. See if the timeout happens later or goes away. If so, then my suspicion about memory is correct.
If that doesn't work, raise the setOpTimeout() and see if that reduces the error or makes it go away.
Also, make sure you're using the latest client.
By the way, I don't think this is directly bulk loading related. It may happen owing to a lot of resource consumption during bulk loading, but it looks like the regular backoff must be working or you're not ever hitting it.
My requirement is to parse two urls at application start point, these two urls have data that is required to be displayed in my application. I am doing this by keeping two urls in a array and running a for loop in the background thread and then insert the values into database in background thread, is it correct way of approaching the problem?
I have posted my code below, help of any kind is welcomed :)
public StartConnecton(SplashScreen splashScreen)
{
urls = new String[2];
urls[0] = "http:xxxxxx.com";
urls[1] = "http:yyy.com";
_dbIRef = new ClassDatabase(1);
_dbIRef.setSID(46);
_splashScreen = (SplashScreen)splashScreen;
_classDatabase = new ClassDatabase();
}
public void run()
{
int size = urls.length;
for(int i = 0; i < size;i++)
{
if(i==0)
{
_id= 1;
}else if(i==1)
{
_id = 0;
}
try{
String conn = this.getConnectionString();
con = (HttpConnection)Connector.open(urls[i]+getConnectionString());
con.setRequestMethod(HttpConnection.GET);
con.setRequestProperty("User-Agent","Profile/MIDP-1.0 Confirguration/CLDC- 1.0");
System.out.println("CONNECTION!!!!!!!!!!!"+con);
code = con.getResponseCode();
System.out.println("CODE!!!!!!!!!!!"+code+"ID"+_id);
if ( code == HttpConnection.HTTP_OK)
{
is = con.openInputStream();
int length = (int) con.getLength();
new Parser(is,_id);
is.close();
con.close();
}
}catch(Exception e)
{
System.out.println("EXCEPTION!!!!!!!!!!"+e);
}
}
_classDatabase.delete("Delete from topnews where sid = 46");
_classDatabase.insertTopNews();
_classDatabase.insertTabBar();
_classDatabase.insertGalleryInfo();
_topNewsScreen = new TopNewsScreen("TopNews");
_splashScreen.swapScreen(_topNewsScreen);
}
Help of any kind is welcomed
A Y
The problems you have at the moment are:
1. The connections are instantiated sequentially.
If the first one fails (server not there, BlackBerry MDS servers down, etc) then you'll have to wait around 30 seconds for the connection.open request to timeout before the second connection is tried.
2. The UI will freeze during connection attempts. I'm guessing you're doing this on the event thread as well, which means the app will freeze whilst the Connection.open is running because this method blocks.
The solution to both of the above problems is to wrap each connection attempt into a separate Thread. Here's a nice example: http://mnarinsky.blogspot.com/2011/03/blackberry-sending-http-request-in.html
3. Redundant code What is that if(i==0) block of code doing? If all you're trying to do is make _id = 1 when i == 0, then just do _id = (i==0) ? 1 : 0;. Alternatively reverse the order which you put the URLs into your array and just use i, and remove the _id variable entirely.