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How to make multiple okhttp3 requests at the same time Android Studio

Good Afternoon, I am still very new to ESP32/android studio coding so I apologize for my beginner terminology. I am currently coding a project where I can control multiple stepper motors at the same exact time from the press of a button on my android application and the motors are connected to certain ESP32 GPIO pins, I am using the okhttp3 client as well. My code is below.
public class Connectivity {
public static String geturl (String url_esp32){
OkHttpClient client = new OkHttpClient();
Request request = new Request.Builder()
.url(url_esp32)
.build();
try
{
Response response = client.newCall(request).execute();
return response.body().string();
} catch(IOException error) {
return error.toString();
}
}
}
above is my connectivity page for connecting to the requests for the esp32.
PBNow.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
// request information from esp32
// PB sandwich now, disable jelly motor
request_to_url("STEP");
request_to_url("DIR");
request_to_url("STEP2");
request_to_url("DIR2");
request_to_url("STEP4");
request_to_url("DIR4");
request_to_url("ledRED");
request_to_url("ledGREEN");
}
});
above is how im calling the requests for the esp32.
The problem I am having is that when these request_to_url lines are going line by line but I want them to all run at the exact same time. Is this possible.
Below are also my request_to_url function and request_data function.
public void request_to_url (String command) {
ConnectivityManager connMgr = (ConnectivityManager)
getSystemService(Context.CONNECTIVITY_SERVICE);
NetworkInfo networkInfo = connMgr.getActiveNetworkInfo();
if(networkInfo != null && networkInfo.isConnected()) {
new request_data().execute("http://" + ip_address + "/" + command);
}else {
Toast.makeText(activity_2.this, "Not connected ", Toast.LENGTH_LONG).show();
}
}
private class request_data extends AsyncTask<String, Void, String> {
#Override
protected String doInBackground(String... url)
{
return Connectivity.geturl(url[0]);
}
#Override
protected void onPostExecute(String result_data) {
if(result_data != null)
{
}else{
Toast.makeText(activity_2.this, "Null data", Toast.LENGTH_LONG).show();
}
}
}
I apologize if the code is very sloppy, I am still very new. Thank you very much.

Besides the messy code in your app required to fire off multiple requests, the ESP32 has very limited network stack and resources, and cannot handle many simultaneous connections. If your app opens too many HTTP connections to the ESP32 at once, some will likely fail or have to wait for others to close.
Instead, you can do it all in a single request and tell the ESP32 to do multiple things at once. Pass the requests as parameters in the URL, like so:
http://ip-address/cmd?step=1&dir=0&ledGREEN=0&ledRED=1
Just have the handler on the ESP32 for the path /cmd look for the presence of each possible parameter and respond to it appropriately.

Fail whe i try to connect my app to webServices

Actully i working in a app, but i have problems to connect my Web services, i have this code:
try{
HttpServices post = new HttpServices ("http://sotem.com.mx/WebServices/controller.php");
post.add("funcion", "test");
System.out.println("Si lo mande///////////////////Jhgfdsa");
String respuesta = post.getRespueta();
System.out.println(respuesta);
Toast.makeText(getApplicationContext(),"Cool: "+respuesta, Toast.LENGTH_SHORT).show();
}catch (Exception ex) {
Toast.makeText(getApplicationContext(),"error: "+ex.toString(), Toast.LENGTH_SHORT).show();
}
but i can make connection, i try to make other thinks, but i can make the thread, i'am new in this part, the app launcher this error:
android os network on main thread exception

It is not okay to do the Network Operation on main thread.. You can use AsyncTask to perform such operations and handle the result in onPostExecute method.
class YourNetworkingTasks extends AsyncTask<Void, Void, Void> {
#Override
protected Void doInBackground(Void... voids) {
try{
HttpServices post = new HttpServices ("http://sotem.com.mx/WebServices/controller.php");
post.add("funcion", "test");
String respuesta = post.getRespueta();
Log.d("Output", respuesta);
// DON'T DO ANY UI CHANGES LIKE TOAST FROM BACKGROUND THREAD.. Toast.makeText(getApplicationContext(),"Cool: "+respuesta, Toast.LENGTH_SHORT).show();
}catch (Exception ex) {
// DON'T DO ANY UI CHANGES LIKE TOAST FROM BACKGROUND THREAD.. Toast.makeText(getApplicationContext(),"error: "+ex.toString(), Toast.LENGTH_SHORT).show();
}
return null;
}
protected void onPostExecute(RSSFeed feed) {
// TODO: YOU CAN MAKE U.I. Changes Like Display text in TextView, TOAST HERE.
// TODO: do something with the result
}
}
And write new YourNetworkingTasks().execute(); to run that code in background thread.
Please also not that since you are using http and not https you may get Network Security Exception and may not get any output due to recent security change in android.

Sending DataMap in a background service android

I'm trying to send the content of a DataMap from an Android device to a wearable. It works fine when the app is in the foreground on my app but once I lock the mobile device it gets stuck at the pendingResult.await() and the wearable doesn't receive any data where as it normal would if I keep the app open.
public void send(final DataMap dataMap) {
new Thread(new Runnable() {
#Override
public void run() {
PutDataMapRequest putDMR = PutDataMapRequest.create(WEARABLE_DATA_PATH);
putDMR.getDataMap().putAll(dataMap);
PendingResult<DataApi.DataItemResult> pendingResult = Wearable.DataApi.putDataItem(googleClient, request);
DataApi.DataItemResult result = pendingResult.await();
if(result.getStatus().isSuccess()) {
Log.d("qwe", "Data item set: " + result.getDataItem().getUri());
}
}
}).start();
}
This method is in a class which extends WearableListenerService and I have added the XML in the AndroidMainfest for the service also. Am I doing something completely wrong or missing something?
Thanks

try to check google api client status for each send.
use blockingConnect when google api client is not connected.

Found out I was doing googleClient.disconnect() in my main activity onStop() which was causing it to hang as googleClient wasn't connected once my app was in the background.

How to force app uninstall in order to update?

I did a mistake that apparently can be solved only by uninstalling and then installing my app again.
I delivered a message to the users, but no-one seems to uninstall it.
AFAIK, if I change the certificate file, the play store won't let me upload the application, and
obviously I don't want to upload a new app.
Is there a way to force uninstall in order to update?
Thanks!

There's no killswitch to remotely force uninstalls (that'd be a security nightmare). What you can do is publish a fixed version on Google Play, and wait for users to upgrade.

I don't know if this can help you but i had the same problem. The solution for me is that i check the app version every time the user opens it and compare it with a version code stored on apache server (in a checkversion.php file).
If versions doesn't match, i show a not cancelable dialog that ask the user to go to market and download the update.
Here is an example (keep in mind that i use Volley library to handle connections):
public class UpdateManager {
private Activity ac;
private HashMap<String,String> params;
public UpdateManager(Activity ac) {
this.ac = ac;
}
public void checkForUpdates() {
Log.d("UpdateManager","checkForUpdates() - Started...");
params = new HashMap<String,String>();
params.put("request","checkforupdates");
try {
params.put("versioncode", String.valueOf(ac.getPackageManager().getPackageInfo(ac.getPackageName(), 0).versionCode));
} catch (NameNotFoundException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
if (Helper.isInternetAvailable(ac)) { //this is a class i made to check internet connection availability
checkAppVersion();
} else { Log.d("UpdateManager","CheckForUpdates(): Impossible to update version due to lack of connection"); }
}
private void checkAppVersion() {
Log.d("UpdateManager","checkAppVersion() - Request started...");
JsonObjectRequest req = new JsonObjectRequest("http://yourserver/checkappversion.php", new JSONObject(params),
new Response.Listener<JSONObject>() {
#Override
public void onResponse(JSONObject response) {
if (response != null && response.has("result")) {
try {
Log.d("UpdateManager","checkAppVersion() - Request finished - Response: "+response.getString("result"));
if (response.getString("result").matches("updaterequested")) { //Update requested. Show the relative dialog
Log.d("UpdateManager","Update requested");
askUserForUpdate();
}
else if (response.getString("result").matches("current")) { //Same version. Do nothing
Log.d("UpdateManager","Version is up to date");
}
else if (response.getString("result").matches("error")) { //You can return an error message if error occurred on server
Log.d("UpdateManager","checkappversion Error - "+response.getString("error"));
}
VolleyLog.v("Response:%n %s", response.toString(4));
} catch (JSONException e) {
e.printStackTrace();
}
}
}
}, new Response.ErrorListener() {
#Override
public void onErrorResponse(VolleyError error) {
Log.e("UpdateManager","Volley Error - "+error.getMessage());
}
});
req.setRetryPolicy(new DefaultRetryPolicy(60000,0,DefaultRetryPolicy.DEFAULT_BACKOFF_MULT));
ConnectionController.getInstance().addToRequestQueue(req);
}
public void askUserForUpdate() {
final Dialog diag = new Dialog(ac);
diag.requestWindowFeature(Window.FEATURE_NO_TITLE);
diag.setContentView(R.layout.updatemanager_requestupdate_dialog);
diag.setCancelable(false);
diag.getWindow().setBackgroundDrawable(new ColorDrawable(android.graphics.Color.TRANSPARENT));
TextView t = (TextView)diag.findViewById(R.id.requestupdate_dialog_main_text);
ImageView im_ok = (ImageView)diag.findViewById(R.id.requestupdate_dialog_ok);
ImageView im_canc = (ImageView)diag.findViewById(R.id.requestupdate_dialog_canc);
t.setText(ac.getResources().getString(R.string.update_manager_askuserforupdate));
im_canc.setOnClickListener(new OnClickListener() {
#Override
public void onClick(View v) {
diag.dismiss();
ac.finish();
}
});
im_ok.setOnClickListener(new OnClickListener() {
#Override
public void onClick(View v) {
Intent intent = new Intent(Intent.ACTION_VIEW);
intent.setData(Uri.parse("market://details?id="+ac.getPackageName()));
diag.dismiss();
ac.startActivity(intent);
ac.finish();
}
});
diag.show();
}
}
You can then use it when your main activity (or maybe login activity) starts like this:
UpdateManager updateManager = new UpdateManager(MainActivity.this); //i assume MainActicity as the calling activity
updateManager.checkForUpdates();
Obviously this has to be implemented into the application code so, the first time, you have to rely only on the user to manually upgrade it. But this can help if you have the same problem in the future.
This is an extract from my personal code so you have to rearrange it to your needings. Hope this helps someone.

Users should be able to go to Settings > Applications > Manage Applications and select the application to be removed. I've never seen a case where the application can't be removed this way, except in the case of built-in applications which require a rooted device to remove.

How can I invoke a method every 5 seconds in android?

I'm working in an application which must send a GPS location every 5 seconds to the server when I choose (auto send button on). I'm new with android so I don't know how I can make an on/off button and how can I invoke the method that sends the data every 5 seconds when the button is on.
The method which it must invoke every 5 seconds:
public void postData() throws ClientProtocolException, IOException, Exception {
String longitude="UK";
String latitude="UK";
String altitiude="UK";
String time="";
String speed="";
getCurrentLocation(); // gets the current location and update mobileLocation variables
if (mobileLocation != null) {
locManager.removeUpdates(locListener); // This needs to stop getting the location data and save the battery power.
longitude = ""+mobileLocation.getLongitude();
latitude = "" + mobileLocation.getLatitude();
altitiude = "" + mobileLocation.getAltitude();
String accuracy = "Accuracy" + mobileLocation.getAccuracy();
time = "" + mobileLocation.getTime();
speed =""+ (int)(4*mobileLocation.getSpeed());
editTextShowLocation.setText(longitude + "\n" + latitude + "\n"
+ altitiude + "\n" + accuracy + "\n" + time+ "\n" + speed);
} else {
editTextShowLocation.setText("Sorry, location is not determined");
}
String url = "http://www.itrack.somee.com/post.aspx?id="+"f1"+"&long="+longitude+"&lat="+latitude+"&alt="+altitiude+"&speed="+speed;
// Create a new HttpClient and Post Header
HttpClient httpclient = new DefaultHttpClient();
HttpPost httppost = new HttpPost(url);
try {
// Execute HTTP Post Request
HttpResponse response = httpclient.execute(httppost);
} catch (ClientProtocolException e) {
// TODO Auto-generated catch block
} catch (IOException e) {
// TODO Auto-generated catch block
}
}

I have faced exactly the same problem, sending location periodically. I've used a handler and its postDelayed method.
The periodic call part of my code looks like this:
private final int FIVE_SECONDS = 5000;
public void scheduleSendLocation() {
handler.postDelayed(new Runnable() {
public void run() {
sendLocation(); // this method will contain your almost-finished HTTP calls
handler.postDelayed(this, FIVE_SECONDS);
}
}, FIVE_SECONDS);
}
Then you just need to call scheduleSendLocation when you want to start your period calls.

Ridcully is right, there is probably no reason to send the current location every 5 seconds. Here is the rational behind that:
You really only care about 2 things about the users location:
Where are they right now?
Have they moved since I got their first location?
So once you get a satisfactory initial location, you can just register to get callbacks whenever the users moves like this:
private LocationListener mLocationListener;
#Override
public void onCreate(final Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
mLocationListener = new LocationListener() {
#Override
public void onLocationChanged(final Location location) {
updateLocation(location);
}
#Override
public void onStatusChanged(final String provider,
final int status, final Bundle extras) {
}
#Override
public void onProviderEnabled(final String provider) {
}
#Override
public void onProviderDisabled(final String provider) {
}
};
}
That being said, you could obviously do what these others have said and run the timer every 5 seconds. The thing is, most good locations take 10-20 seconds to run, so you might only want to run it in that interval. Also FYI, this WILL kill battery

Look at the AlarmManager class http://developer.android.com/reference/android/app/AlarmManager.html and particularly the setRepeating function. Its going to be a bit more complicated than you'd like though.

You can use a Timer. But I think it would be better if you only send the position of it has changed a certain distance from the last one you sent. This way you'd send way less data without losing any information.