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How can I update Recyclerview with Broadcast Receiver from Service class?

I am working on music player app and I have included the basic functionality like Play, Pause, next and Previous tracks using service class.
Now I want to update myrecyclerview UI according to the action that user clicks(eg: on the play, there should be an image of the selected element in recyclerview).
I thought to use Broadcast Receiver that service class will broadcast on different actions and then recyclerview can update according to the broadcast action. But how do I add such functionality?

You'd need an in-activity broadcast receiver. Such receivers are registered when your activity is shown and unregistered once it's hidden.
public class MainActivity extends Activity {
private final BroadcastReceiver mReceiver = new BroadcastReceiver() {
#Override
public void onReceive(Context context, Intent intent) {
// Here update your RecyclerView
}
};
#Override
protected void onResume() {
super.onResume();
IntentFilter filter = new IntentFilter(YourService.YOUR_CUSTOM_ACTION);
registerReceiver(mReceiver, filter);
}
#Override
protected void onPause() {
super.onPause();
unregisterReceiver(mReceiver);
}
}
And in your service, simply send broadcasts:
Intent intent = new Intent(YOUR_CUSTOM_ACTION);
// put extras in the intent as you wish
sendBroadcast(intent);

Closing running Application from BroadcastReceiver

In my App, there is a condition which check every day and if it gets true then I want my App get close in between the run like a crash and stack also gets clear .
I have try and tested many solutions but didn't find the one that works the way i wanted .
My BroadcastReceiver:
public void onReceive(Context context, Intent intent) {
PreferenceForApp prefs = new PreferenceForApp(context);
Bundle bundle = intent.getExtras();
if (bundle!=null){
if(bundle.containsKey("exception")) {
// String e = bundle.getString("exception")
if(bundle.get("exception").toString().equalsIgnoreCase("http request failed with error_msg No Match Found")) {
prefs.setIsDeviceValidated(false);
prefs.setIsLogIn(false);
Log.i("Time", "Exception Occur");
Intent CSPIntent=new Intent(context,CSPLoginActivity.class);
CSPIntent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK|Intent.FLAG_ACTIVITY_CLEAR_TOP);
CSPIntent.putExtra("close_activity", true);
Log.i("Time", "IntentExit");
context.startActivity(CSPIntent);
}
}
}
}
}
And code to finish in an Activity I am calling from broadcastReceiver:
if (getIntent().getBooleanExtra("close_activity",false)) {
Log.i("Time", "ExitCSPLogin");
this.finish();
}
This code is not closing App in between the run.

You need to register BroadcastReceiver in your activity and send broadcast to BroadcastReceiver when you want to close application.
In your Activity try this:
IntentFilter intentFilter = new IntentFilter();
intentFilter.addAction("com.package.ACTION_CLOSE");;
BroadcastReceiver Receiver = new BroadcastReceiver() {
#Override
public void onReceive(Context context, Intent intent) {
finish();
}
};
registerReceiver(Receiver, intentFilter);
in onDestroy() method of you Activity unregister BroadcastReceiver:
#Override
protected void onDestroy() {
unregisterReceiver(Receiver);
super.onDestroy();
}
Now when you want close application send broadcast to BroadcastReceiver:
Intent broadcastIntent = new Intent();
broadcastIntent.setAction("com.package.ACTION_CLOSE");
sendBroadcast(broadcastIntent);
Hope this helps!

you have to check below condition in your app's mainActivity's onCreate method every time when user enter in your app. or in onResume if you want to to close your app immediately
if (!prefs.getIsDeviceValidated()) {
Log.i("Time", "ExitCSPLogin");
this.finish();
}
i assume you have more then one activity in your app, so insted of check above flag in every activity we 'll put it in main activity. allow user to use your app until he/she come at mainActivity
Note: create Broadcast Receiver for your App(add in manifest), not for specific activity

Android: how to send object from BroadcastReceiver to running Activity

I have a class that extends BroadcastReceiver that reads new sms
public class SmsReceiver extends BroadcastReceiver
{
// reading sms
// I want to send the sms text to my main activity
}
And have another class in the same app that is my main Activity.
So when I receive new sms, I want to send its content to my main Activity that is already running and display it.
How can I do that?
I would be thankful for some code samples :)

i can suggest you two possibilities
send new broadcasts from this receiver to a new receiver which is registered inside your activity
register this receiver inside your activity and reduce the hassle
i guess option two is more suitable
this is how you may register a broadcast receiver inside your activity class:
IntentFilter filter = new IntentFilter();
public void onResume(){
filter.addAction("action_string_1");
filter.addAction("action_string_2");
registerReceiver(receiver, filter);
}
public void onPause(){
unregisterReceiver(receiver);
}
BroadcastReceiver receiver = new BroadcastReceiver() {
#Override
public void onReceive(Context context, Intent intent) {
String action = intent.getAction();
if(action.equals("action_string_1")){
//do something here
}
else if(action.equals("action_string_2")){
//do somethign here
}
}
};

service displays points on map android

i have a android service running in the background which receives the coordinates from the server every few seconds. i am not sure how do i display the coordinates on a map every time the service receives a response from the server. kindly help or give an idea.
thanks

I don't know any tutorials on this, but here's a version of mine:
To send a broadcast, you use the 'sendBroadcast(Intent i)' method of the Context class. The Service class extends Context, so you can access it from your implementation.
So in your Service goes:
public static final String BROADCAST_ACTION="com.yourservice.update";
public void onStart( Intent intent, int startId ) {
...
Intent broadcastIntent = new Intent(BROADCAST_ACTION);
sendBroadcast(broadcastIntent);
...
}
You have to register a receiver for this broadcast in you Activity (possibly before you start boradcasting them), like this:
private BroadcastReceiver receiver=new BroadcastReceiver() {
public void onReceive(Context context, Intent intent) {
//Here goes handling the stuff you got from the service
Bundle extras = intent.getExtras();
if(extras != null)processUIUpdate(extras);
}
};
public void onResume() {
...
//Register for the update broadcasts from the torrent service
registerReceiver(receiver, new IntentFilter(YourService.BROADCAST_ACTION));
...
}
Don't forget to deregister when the Activity goes background:
public void onPause() {
...
//Deregister for the update broadcast from the torrent service
unregisterReceiver(receiver);
...
}
This should work.

Your service could broadcast intents whenever it wants to update the displayed location on the map. The Activity displaying the map should register a receiver for that boradcast, and the boradcast's intent can hold the values for lat. and long.

Android - Sending data from an activity to a service

I've a local service that is started in my main activity. The service is responsible for network I/O. It also interacts with other activities in my application. Till, now the service was only "providing" data to activity (using callbacks and not Intents.)
Now I need to send data (custom objects) from my activities to the service. I understand one way to do it using Intents. I know it is possible to receive an Intent in the service by overriding the onStartCommand() in my service. But it's not clear to me if the onStartCommand will be invoked every time I broadcast an Intent from my sending activity. Can a Service also be BroadcastReceiver ? If yes - how ?
Thanks.

You can create a BroadcastReceiver object in the service and register it to listen to any broadcast event you want. It's something like this:
BroadcastReceiver mScreenStateReceiver = new BroadcastReceiver() {
#Override
public void onReceive(Context context, Intent intent) {
//handle the broadcast event here
}
};
#Override
public void onCreate() {
super.onCreate();
IntentFilter filter = new IntentFilter(Intent.ACTION_SCREEN_OFF);
filter.addAction(Intent.ACTION_SCREEN_ON);
registerReceiver(mScreenStateReceiver, filter);
}
#Override
public void onDestroy() {
super.onDestroy();
unregisterReceiver(mScreenStateReceiver);
}
Regards,