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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

send action from receiver to activity?

I am using broadcast receiver in my app to detect incomming call and it works fine. But problem is I can not send action to activity. I mean.. I want do something in activity not in receiver. I read many tutorial but they all are performing action in receiver. Any idea ?

You can declare a BroadcastReceiver as inner class of the Activity. In this case you can directly call activity's methods:
public class MyActivity extends Activity {
private final BroadcastReceiver receiver = new BroadcastReceiver() {
#Override
public void onReceive(Context context, Intent intent) {
activityMethod();
}
};
private final IntentFilter filter = new IntentFilter("android.intent.action.PHONE_STATE");
#Override
protected void onStart() {
super.onResume();
registerReceiver(receiver, filter);
}
#Override
protected void onStop() {
super.onPause();
unregisterReceiver(receiver);
}
private void activityMethod() {
}
}

You can start the Activity using an Intent and put a command code in the Intent extra fields. In your Activity you can then decide the behaviour based on the command code or resort to a default behaviour if none is present.

You can start an activity from your receiver via the normal means:
#Override
public void onReceive(Context context, Intent intent) {
Intent i = new Intent(context, YourActivity.class);
startActivity(i);
}
Note though that the user is going to expect that the phone application starts up since they are receiving a phone call. It is very likely a bad idea to hijack the phone call by dumping your own activity on top of the stock dialer app.

Android - Broadcast Receiver launch a singletask Activity

I have a broadcast receiver which will launch an Activity onReceive.
When launched, this activity will perform a long task and call finish() at the end.
I do not want to trigger another launch of Activity when the previous Activity is still performing the long task. How can I launch only a singletask activity? I have set this in the manifest.
android:launchMode="singleTask"
In my onReceive method,
public void onReceive(Context context, Intent intent) {
Intent activity = new Intent(context, Preview.class);
activity.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
context.startActivity(activity);
}
Don't seems to work.
The Activity class actually is a MediaRecorder which will record a video clip (say 10 sec). Thus I do not want to trigger another Activity while this recording is still incomplete.

You just need to have some way for your activity to communicate to your receiver to let it know whether or not it is already running. If you have that then you can make an if statement in the receiver that will keep it from launching multiples.
One option is a static boolean in your activity that indicates whether or not you are currently running. Then you can check that boolean from the receiver, and if it is true, then don't call startActivity().
your activity would need something like this:
public YourActivity extends Activity{
public static isRunning = false;
public void onStart(){
...
isRunning = true;
}
public void onStop(){
...
isRunning = false;
}
}
now in your receiver you can make a simple if statement that will check the value of isRunning:
public void onReceive(Context context, Intent intent) {
if(YourActivity.isRunning == false){
Intent activity = new Intent(context, Preview.class);
activity.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
context.startActivity(activity);
}
}

Please add these flags.
public void onReceive(Context context, Intent intent) {
Intent activity = new Intent(context, Preview.class);
activity.addFlags(Intent.FLAG_ACTIVITY_REORDER_TO_FRONT | Intent.FLAG_ACTIVITY_CLEAR_TOP |Intent.FLAG_ACTIVITY_BROUGHT_TO_FRONT);
context.startActivity(activity);
}

Finishing an Activity from a Broadcast Receiver

I have an Activity that I display as modeless when the phone rings (over the phone app). I would like to finish the Activity when either of the following events occur. The first is if I touch anywhere outside the Activity (this is not a problem), the second is if the ringing stops. I am listening for IDLE_STATE in the broadcast receiver but I am not sure on how to call the finish on the activity when I see it. The receiver is not registered by the activity but by the Manifest.xml

write the code in your receiving broadcast now this will send another broad cast with the intent named "com.hello.action"
Intent local = new Intent();
local.setAction("com.hello.action");
sendBroadcast(local);
Now catch this intent in the activity with you want to finish it and then call the super.finish() on the onReceive method of your receiver
like this
public class fileNamefilter extends Activity {
ArrayAdapter<String> adapter;
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
IntentFilter filter = new IntentFilter();
filter.addAction("com.hello.action");
registerReceiver(receiver, filter);
}
BroadcastReceiver receiver = new BroadcastReceiver() {
#Override
public void onReceive(Context context, Intent intent) {
finish();
}
};
public void finish() {
super.finish();
};
}
this will finish the activity

What if you register another broadcast receiver from the activity. Then, when you want to kill it, send a broadcast message from the broadcast receiver that you mentioned.

I actually ended up adding a PhoneStateListener in the Activity to listen for IDLE_STATE.

After a long R&D over internet i have solved my problem. The below code is helpful if you start an activity from broadcast receiver and
clear all activity stack instance.
#Override
public void onBackPressed() {
if (drawer.isDrawerOpen(GravityCompat.START)) {
drawer.closeDrawer(GravityCompat.START);
} else {
moveTaskToBack(true);
}
}

I used this code to solve my problem. finish is the method of Activity, so call Activity and context like:
if (state.equals(TelephonyManager.EXTRA_STATE_IDLE)) {
Log.e(TAG, "Inside EXTRA_STATE_IDLE");
((Activity) arg0).finish();
}