I have an application which allows to read and write (notify) in BLE. Following the sample example, I created my own read and write functions in the class BluetoothLeService as follows:
public void readCharacteristic()
{
//My function
}
public void writeCustomCharacteristic(int value)
{
//My function
}
I want to keep read and write data when the application is in background. Hence, I must to make a service to do it. A simple structure of a service will be
public class backgroundservice extends Service
{
private static final String TAG = "MyService";
#Override
public void onCreate() {
super.onCreate();
Log.d(TAG, "onCreate");
}
#Override
public IBinder onBind(Intent intent) {
return null;
}
public void onDestroy() {
Log.d(TAG, "onDestroy");
}
#Override
public int onStartCommand(Intent intent, int flags, int startId)
{
return START_NOT_STICKY;
}
}
My question is how can I read/write data when my application is in background? If I use above service, which function do I need to use to call readCharacteristic() and writeCustomCharacteristic(int value)? For example, the writeCustomCharacteristic(int value) is called every 10 seconds. Thank all
Related
I created an app that reads books to the user.
The user needs to be able to continue reading
from the same position as he was in a previous app session.
How do i do something like that, if a process kill can occur anytime?
you can create here a service class in your app like this and create an api with your backend too :-
Service Class OnClearFromRecentService.class:-
public class OnClearFromRecentService extends Service {
#Override
public IBinder onBind(Intent intent) {
return null;
}
#Override
public int onStartCommand(Intent intent, int flags, int startId) {
return START_NOT_STICKY;
}
#Override
public void onDestroy() {
super.onDestroy();
}
#Override
public void onTaskRemoved(Intent rootIntent) {
callApi();
stopSelf();
}
public void callApi(){
//set your api here
}
}
and set this service class in your manifeast :-
<service
android:name=".halper.OnClearFromRecentService"
android:stopWithTask="false" />
and start this service when your video is play :-
OnClearFromRecentService onClearFromRecentService = new OnClearFromRecentService();
or stop your service where your you need to stop service like this:-
onClearFromRecentService.onTaskRemoved(new Intent(LandingScreen.this, OnClearFromRecentService.class));
I am developing App-Locker app and i have background service which is running. But i want the exact solution to trigger one function inside that background service when any application is launch or open in mobile.
I am using the below service which runs continuously.
public class NotificationService extends Service {
public NotificationService() {
}
#Override
public IBinder onBind(Intent intent)
{
Log.e("Noftication serveric ", " Onbinddddd");
return null;
}
#Override
public int onStartCommand(Intent intent, int flags, int startId)
{
super.onStartCommand(intent, flags, startId);
return START_STICKY;
}
#Override
public void onDestroy()
{
super.onDestroy();
//Starting Broadcast on destroy method, where this service is called again to run
Intent restartService = new Intent("RestartService");
sendBroadcast(restartService);
}
public void Trigger_Me_If_Any_App_Launch()
{
//This function should be called if any app launch
}
}
So I have code that I want called when my application is closed. Not just when it is sent to the background or the surface is destroyed. How do I do this? Is there a method that I can override in a SurfaceView or Activity class?
New Edit - current BackgroundService class:
public class BackgroundService extends Service {
private String savedString;
public void onCreate() {
System.out.println("Service created");
super.onCreate();
}
public int onStartCommand(Intent intent, int flags, int startId) {
System.out.println("start command: ");
savedString = intent.getStringExtra("myString);
return super.onStartCommand(intent, flags, startId);
}
public IBinder onBind(Intent intent) {
return null;
}
public void onTaskRemoved(Intent rootIntent) {
System.out.println("the saved string was: " + savedString);
super.onTaskRemoved(rootIntent);
}
public void onDestroy() {
System.out.println("destroyed service");
super.onDestroy();
}
}
Where I then have this in my other class:
Intent serviceIntent = new Intent(activity.getApplicationContext(), BackgroundService.class);
serviceIntent.putExtra("myString", "this is my saved string");
activity.startService(serviceIntent);
you need to add a background service
public class BackgroundServices extends Service
{
#Override
public void onCreate() {
Toast.makeText(this, "start", Toast.LENGTH_SHORT).show();
super.onCreate();
}
#Override
public int onStartCommand(Intent intent, int flags, int startId) {
}
#Nullable
#Override
public IBinder onBind(Intent intent) {
return null;
}
#Override
public void onDestroy() {
super.onDestroy();
}
}
then in your activity. where you want to trigger this service
use
startService(new Intent(getBaseContext(), BackgroundServices.class));
in your case it will be call on onDestory function of that activity
Yes when the process is terminated
That is not possible in general. Nothing in your app is called when the process is terminated.
For example when you open the running apps screen, and swipe away the app to stop it from running
That is a task removal. It may result in your process being terminated, and there are many ways in which your process can be terminated that has nothing to do with task removal.
To detect task removal, override onTaskRemoved() in a Service.
I have a function in a service as follows:
public class ServiceA extends Service {
#Override
public void onCreate() {
super.onCreate();
Log.d(TAG, "onCreate");
}
#Override
public int onStartCommand(Intent intent, int flags, int startId) {
return START_NOT_STICKY;
}
private final IBinder mBinder = new LocalBinder();
public void readFunc() {
//I have a function in here
}
}
I want to call the readFunc() in the service B. Could I do it in Android? Thank all. This is my service B
public class serviceB extends Service {
#Override
public void onCreate() {
super.onCreate();
Log.d(TAG, "onCreate");
}
#Override
public IBinder onBind(Intent intent) {
return null;
}
#Override
public int onStartCommand(Intent intent, int flags, int startId)
{
IntentFilter intentFilter = new IntentFilter();
intentFilter.addAction("A");
intentFilter.addAction("B");
registerReceiver(broadcastReceiver, intentFilter);
return START_STICKY;
}
BroadcastReceiver broadcastReceiver = new BroadcastReceiver() {
#Override
public void onReceive(Context context, Intent intent) {
switch (intent.getAction()) {
case "A":
Log.d(TAG,"A");
//Call the function here
break;
case "B":
Log.d(TAG,"B");
break;
}
}
};
}
Well, you COULD do it, just instancing a new ServiceA and calling the function, but you should not do it like that. Services are not meant to be instantiated just to call a function which is not even part of the Service functionality. You have different options:
You could make readFunc() static if it does not modify variables of the class and you think it should belong to ServiceA and not to ServiceB. I don't think this is a goog approach in your case.
You could create a class ServiceAB which has readFunc(), and the define both ServiceA and B as "extends ServiceAB". Then both classes would inherit this function and you could just call readFunc() in both of them. I think this would be the correct approach in your case: both classes need some common functionality.
You could have readFunc() in a different class, and the instantiate it to use it in each of your services.
The way I would do it:
public class ServiceAB extends Service {
#Override
public void onCreate() {
super.onCreate();
Log.d(TAG, "onCreate");
}
public void readFunc() {
//I have a function in here
}
}
Then:
public class serviceB extends ServiceAB {
#Override
public IBinder onBind(Intent intent) {
return null;
}
#Override
public int onStartCommand(Intent intent, int flags, int startId)
{
IntentFilter intentFilter = new IntentFilter();
intentFilter.addAction("A");
intentFilter.addAction("B");
registerReceiver(broadcastReceiver, intentFilter);
return START_STICKY;
}
BroadcastReceiver broadcastReceiver = new BroadcastReceiver() {
#Override
public void onReceive(Context context, Intent intent) {
switch (intent.getAction()) {
case "A":
Log.d(TAG,"A");
readFunc(); //Just call the function
break;
case "B":
Log.d(TAG,"B");
break;
}
}
};
}
And ServiceA:
public class ServiceA extends ServiceAB {
#Override
public int onStartCommand(Intent intent, int flags, int startId) {
return START_NOT_STICKY;
}
private final IBinder mBinder = new LocalBinder();
}
Quoting #Kingfisher Phuoc here and #Mr Snowflake here
there are three obvious ways to communicate with services and EventBus:
Using Intents
Using AIDL
Using the service object itself (as singleton)
EventBus
In your case, I'd go with option 3. Make a static reference to the service it self and populate it in onCreate():
void onCreate(Intent i) {
sInstance = this;
}
Make a static function MyService getInstance(), which returns the static sInstance.
Then in Activity.onCreate() you start the service,
asynchronously wait until the service is actually started (you could have your service notify your app it's ready by sending an Intent to the activity.) and get its instance.
When you have the instance, register your service listener object to you service and you are set.
NOTE: when editing Views inside the Activity you should modify them in the UI thread, the service will probably run its own Thread, so you need to call Activity.runOnUiThread().
The last thing you need to do is to remove the reference to you listener object in Activity.onPause(), otherwise an instance of your activity context will leak, not good.
NOTE: This method is only useful when your application/Activity/task is the only process that will access your service. If this is not the case you have to use option 1. or 2.
I have two applications. One run service and second is only small app. I want to put some data to service in first app, but I want to get this data in second app. How can I do that? I need that because when I use home button on second app and return I need check if id was changed. I think about run service with id in first app and second app when onResume check that id.
This is code service class:
public class ServiceId extends Service{
private int id;
#Override
public IBinder onBind(Intent intent) {
// TODO Auto-generated method stub
return null;
}
#Override
public void onCreate() {
}
#Override
public void onDestroy() {
}
#Override
public void onStart(Intent intent, int startid) {
id = MainActivity.getApplicationId();
Log.v("Start", "Webservice started");
}
}
I start service in mainactivity:
startService(new Intent(MainActivity.this, ServiceId.class));
how get that id in other application?