In my android project I need to detect and read SMS texts as they come in, then call a function from another class.
How can I put the below code in a class and define it properly in the manifest. If I put this on another Java file, then I don't know how to call a function from another Java file.
I tried putting this code in my main class but in my app, it just crashed.
public class SMSReceiverActivity extends BroadcastReceiver {
#Override
public void onReceive(Context context, Intent intent) {
// Parse the SMS.
Bundle bundle = intent.getExtras();
SmsMessage[] msgs = null;
String str = "";
if (bundle != null)
{
// Retrieve the SMS.
Object[] pdus = (Object[]) bundle.get("pdus");
msgs = new SmsMessage[pdus.length];
for (int i=0; i<msgs.length; i++)
{
msgs[i] = SmsMessage.createFromPdu((byte[])pdus[i]);
// In case of a particular App / Service.
//if(msgs[i].getOriginatingAddress().equals("+91XXX"))
//{
//str += "SMS from " + msgs[i].getOriginatingAddress();
//str += " :";
str += msgs[i].getMessageBody().toString();
str += "\n";
//}
}
if (str != "") { // remove the last \n
str = str.substring(0, str.length()-1);
}
Reusable_CodeActivity.alert(my_ViewActivity.this, "AAAAAAAAAAA");
try {
//my_ViewActivity.this.handle_incoming_message(str);
} catch(Exception e) {
}
}
}
}
Your code for receiving SMS is correct. but when you are using BroadCastReceiver in Activity class you need to unregister it as follows in onStop() method. I think this is the reason your activity was crushing.
#Override
protected void onStop()
{
unregisterReceiver(mReceiver);
super.onStop();
}
If I understand your question correctly you want to receive broadcasts (when an SMS arrives) while your Activity is showing.
If so I found a nice pattern to do this a while back (Cant remember where I got it from, would be nice to give credit to the original author).
First, create an interface:
public interface Receiver {
public void onReceive(Context context, Intent intent);
}
Now create a subclass of BroadcastReceiver which we can dynamically register at runtime:
public class PortableReceiver extends BroadcastReceiver {
private Receiver mReceiver;
public void setReceiver(Receiver receiver) {
mReceiver = receiver;
}
public Receiver getReceiver() {
return mReceiver;
}
#Override
public void onReceive(Context context, Intent intent) {
if (mReceiver != null)
mReceiver.onReceive(context, intent);
else
Log.w("PortableReceiver", "Dropping received Result");
}
}
Now we can use a PortableReceiver in the activity class:
public class MyActivity implements Receiver {
private PortableReceiver mReceiver;
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
mReceiver = new PortableReceiver();
mReceiver.setReceiver(this);
}
#Override
public void onResume() {
super.onResume();
// Register the receiver
IntentFilter filter = new IntentFilter();
filter.addAction("_my_intent_action"); //TODO: add actions to filter just as you would in your AndroidManifest
registerReceiver(mReceiver, filter, null, null);
}
#Override
public void onPause() {
super.onPause();
unregisterReceiver(mReceiver);
}
#Override
public void onReceive(Context context, Intent intent) {
//TODO: Your code goes here!
}
}
Now you have your Activity class directly handling the Broadcast, so you can access all the functionality it has available.
Note that if you want to start an activity from a BroadcastReceiver, thats a little different. If thats the case, I recommend you check out http://www.vogella.com/articles/AndroidServices/article.html#pre_broadcastreceiver
Related
In my application where the app receives a new sms message, I want the listview to update it it immediately with the new message shown in the listview. I tried using the example code of the broadcast receiver code but it didn't work, so I'm now trying to use a timer to update the listview every second and show the latest message received but this isn't working either.
final Handler handler = new Handler();
handler.postDelayed(new Runnable()
{
#Override
public void run()
{
inboxArrayAdapter.notifyDataSetChanged();
((BaseAdapter)inboxmessages.getAdapter()).notifyDataSetChanged();
handler.postDelayed(this, 1000 );
}
}, 1000);
return view;
Original attempt of using BroadcastReceiver to update listview when new SMS message recieved.
SmSBroadcastReceiver.java
public class SmsBroadcastReceiver extends BroadcastReceiver
{
public static final String SMS_BUNDLE = "pdus";
// https://javapapers.com/android/android-receive-sms-tutorial/
public void onReceive(Context context, Intent intent)
{
Bundle intentExtras = intent.getExtras();
if (intentExtras != null)
{
Object[] sms = (Object[]) intentExtras.get(SMS_BUNDLE);
String smsMessageStr = "";
for (int i = 0; i < sms.length; i++)
{
// Get sms message
SmsMessage smsMessage = SmsMessage.createFromPdu((byte[]) sms[i]);
// Get content and number
String smsBody = smsMessage.getMessageBody().toString();
String address = smsMessage.getOriginatingAddress();
// Create display message
smsMessageStr += "SMS From: " + address + "\n";
smsMessageStr += smsBody + "\n";
// Add it to the list
CommandsFragment inst = CommandsFragment.instance();
inst.updateList(smsMessageStr);
}
CommandsFragment inst = CommandsFragment.instance();
inst.updateList(smsMessageStr);
}
}
}
CommandsFragment.java
public static CommandsFragment instance()
{
return inst;
}
#Override
public void onStart() {
super.onStart();
inst = this;
}
public static CommandsFragment newInstance()
{
CommandsFragment fragment = new CommandsFragment();
return fragment;
}
public void updateList(final String smsMessage)
{
inboxArrayAdapter.insert(smsMessage, 0);
inboxArrayAdapter.notifyDataSetChanged();
}
Put the listview update code inside a method in the Activity where the listview belongs, and call that method from broadcast receiver's onReceive. It would definitely work. Also check the code for whether you are updating the list view properly.
public class SmsBroadcastReceiver extends BroadcastReceiver {
#Override
public void onReceive(Context paramContext, Intent intent) { // change the parameters depending upon your requirements
// do something here with the sms received if necessary
// then call the listview update method here
}
}
Also to add to the answer don't forget to have this below in the AndroidManifest.xml file
</activity>
<receiver android:name=".SmsBroadcastReceiver">
<intent-filter>
<action android:name="android.provider.Telephony.SMS_RECEIVED" />
</intent-filter>
</receiver>
</application>
This above also fixed the solution for me. Thanks for your help guys.
I need to check if my registered receiver is still registered if not how do i check it any methods?
There is no API function to check if a receiver is registered. The workaround is to put your code in a try catch block as done below.
try {
//Register or UnRegister your broadcast receiver here
} catch(IllegalArgumentException e) {
e.printStackTrace();
}
I am not sure the API provides directly an API, if you consider this thread:
I was wondering the same thing.
In my case I have a BroadcastReceiver implementation that calls
Context#unregisterReceiver(BroadcastReceiver) passing itself as the argument after handling the Intent that it receives.
There is a small chance that the receiver's onReceive(Context, Intent) method is called
more than once, since it is registered with multiple IntentFilters, creating the potential for an IllegalArgumentException being thrown from Context#unregisterReceiver(BroadcastReceiver).
In my case, I can store a private synchronized member to check before calling Context#unregisterReceiver(BroadcastReceiver), but it would be
much cleaner if the API provided a check method.
simplest solution
in receiver:
public class MyReceiver extends BroadcastReceiver {
public boolean isRegistered;
/**
* register receiver
* #param context - Context
* #param filter - Intent Filter
* #return see Context.registerReceiver(BroadcastReceiver,IntentFilter)
*/
public Intent register(Context context, IntentFilter filter) {
try {
// ceph3us note:
// here I propose to create
// a isRegistered(Contex) method
// as you can register receiver on different context
// so you need to match against the same one :)
// example by storing a list of weak references
// see LoadedApk.class - receiver dispatcher
// its and ArrayMap there for example
return !isRegistered
? context.registerReceiver(this, filter)
: null;
} finally {
isRegistered = true;
}
}
/**
* unregister received
* #param context - context
* #return true if was registered else false
*/
public boolean unregister(Context context) {
// additional work match on context before unregister
// eg store weak ref in register then compare in unregister
// if match same instance
return isRegistered
&& unregisterInternal(context);
}
private boolean unregisterInternal(Context context) {
context.unregisterReceiver(this);
isRegistered = false;
return true;
}
// rest implementation here
// or make this an abstract class as template :)
...
}
in code:
MyReceiver myReceiver = new MyReceiver();
myReceiver.register(Context, IntentFilter); // register
myReceiver.unregister(Context); // unregister
ad 1
-- in reply to:
This really isn't that elegant because you have to remember to set the
isRegistered flag after you register. – Stealth Rabbi
-- "more ellegant way" added method in receiver to register and set flag
this won't work If you restart the device or if your app got killed by
OS. – amin 6 hours ago
#amin - see lifetime of in code (not system registered by manifest entry) registered receiver :)
I am using this solution
public class ReceiverManager {
private WeakReference<Context> cReference;
private static List<BroadcastReceiver> receivers = new ArrayList<BroadcastReceiver>();
private static ReceiverManager ref;
private ReceiverManager(Context context) {
cReference = new WeakReference<>(context);
}
public static synchronized ReceiverManager init(Context context) {
if (ref == null) ref = new ReceiverManager(context);
return ref;
}
public Intent registerReceiver(BroadcastReceiver receiver, IntentFilter intentFilter) {
receivers.add(receiver);
Intent intent = cReference.get().registerReceiver(receiver, intentFilter);
Log.i(getClass().getSimpleName(), "registered receiver: " + receiver + " with filter: " + intentFilter);
Log.i(getClass().getSimpleName(), "receiver Intent: " + intent);
return intent;
}
public boolean isReceiverRegistered(BroadcastReceiver receiver) {
boolean registered = receivers.contains(receiver);
Log.i(getClass().getSimpleName(), "is receiver " + receiver + " registered? " + registered);
return registered;
}
public void unregisterReceiver(BroadcastReceiver receiver) {
if (isReceiverRegistered(receiver)) {
receivers.remove(receiver);
cReference.get().unregisterReceiver(receiver);
Log.i(getClass().getSimpleName(), "unregistered receiver: " + receiver);
}
}
}
You have several options
You can put a flag into your class or activity. Put a boolean variable into your class and look at this flag to know if you have the Receiver registered.
Create a class that extends the Receiver and there you can use:
Singleton pattern for only have one instance of this class in your project.
Implement the methods for know if the Receiver is register.
You have to use try/catch:
try {
if (receiver!=null) {
Activity.this.unregisterReceiver(receiver);
}
} catch (IllegalArgumentException e) {
e.printStackTrace();
}
You can do it easy....
1) create a boolean variable ...
private boolean bolBroacastRegistred;
2) When you register your Broadcast Receiver, set it to TRUE
...
bolBroacastRegistred = true;
this.registerReceiver(mReceiver, new IntentFilter(BluetoothDevice.ACTION_FOUND));
....
3) In the onPause() do it...
if (bolBroacastRegistred) {
this.unregisterReceiver(mReceiver);
bolBroacastRegistred = false
}
Just it, and now, you will not receive more exception error message on onPause().
Tip1: Always use the unregisterReceiver() in onPause() not in onDestroy()
Tip2: Dont forget to set the bolBroadcastRegistred variable to FALSE when run the unregisterReceive()
Success!
If you put this on onDestroy or onStop method. I think that when the activity has been created again the MessageReciver wasn't being created.
#Override
public void onDestroy (){
super.onDestroy();
LocalBroadcastManager.getInstance(context).unregisterReceiver(mMessageReceiver);
}
Personally I use the method of calling unregisterReceiver and swallowing the exception if it's thrown. I agree this is ugly but the best method currently provided.
I've raised a feature request to get a boolean method to check if a receiver is registered added to the Android API. Please support it here if you want to see it added:
https://code.google.com/p/android/issues/detail?id=73718
I used Intent to let Broadcast Receiver know about Handler instance of main Activity thread and used Message to pass a message to Main activity
I have used such mechanism to check if Broadcast Receiver is already registered or not. Sometimes it is needed when you register your Broadcast Receiver dynamically and do not want to make it twice or you present to the user if Broadcast Receiver is running.
Main activity:
public class Example extends Activity {
private BroadCastReceiver_example br_exemple;
final Messenger mMessenger = new Messenger(new IncomingHandler());
private boolean running = false;
static class IncomingHandler extends Handler {
#Override
public void handleMessage(Message msg) {
running = false;
switch (msg.what) {
case BroadCastReceiver_example.ALIVE:
running = true;
....
break;
default:
super.handleMessage(msg);
}
}
}
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
IntentFilter filter = new IntentFilter();
filter.addAction("pl.example.CHECK_RECEIVER");
br_exemple = new BroadCastReceiver_example();
getApplicationContext().registerReceiver(br_exemple , filter); //register the Receiver
}
// call it whenever you want to check if Broadcast Receiver is running.
private void check_broadcastRunning() {
/**
* checkBroadcastHandler - the handler will start runnable which will check if Broadcast Receiver is running
*/
Handler checkBroadcastHandler = null;
/**
* checkBroadcastRunnable - the runnable which will check if Broadcast Receiver is running
*/
Runnable checkBroadcastRunnable = null;
Intent checkBroadCastState = new Intent();
checkBroadCastState .setAction("pl.example.CHECK_RECEIVER");
checkBroadCastState .putExtra("mainView", mMessenger);
this.sendBroadcast(checkBroadCastState );
Log.d(TAG,"check if broadcast is running");
checkBroadcastHandler = new Handler();
checkBroadcastRunnable = new Runnable(){
public void run(){
if (running == true) {
Log.d(TAG,"broadcast is running");
}
else {
Log.d(TAG,"broadcast is not running");
}
}
};
checkBroadcastHandler.postDelayed(checkBroadcastRunnable,100);
return;
}
.............
}
Broadcast Receiver:
public class BroadCastReceiver_example extends BroadcastReceiver {
public static final int ALIVE = 1;
#Override
public void onReceive(Context context, Intent intent) {
// TODO Auto-generated method stub
Bundle extras = intent.getExtras();
String action = intent.getAction();
if (action.equals("pl.example.CHECK_RECEIVER")) {
Log.d(TAG, "Received broadcast live checker");
Messenger mainAppMessanger = (Messenger) extras.get("mainView");
try {
mainAppMessanger.send(Message.obtain(null, ALIVE));
} catch (RemoteException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
.........
}
}
i put this code in my parent activity
List registeredReceivers = new ArrayList<>();
#Override
public Intent registerReceiver(BroadcastReceiver receiver, IntentFilter filter) {
registeredReceivers.add(System.identityHashCode(receiver));
return super.registerReceiver(receiver, filter);
}
#Override
public void unregisterReceiver(BroadcastReceiver receiver) {
if(registeredReceivers.contains(System.identityHashCode(receiver)))
super.unregisterReceiver(receiver);
}
I get your problem, I faced the same problem in my Application. I was calling registerReceiver() multiple time within the application.
A simple solution to this problem is to call the registerReceiver() in your Custom Application Class. This will ensure that your Broadcast receiver will be called only one in your entire Application lifecycle.
public class YourApplication extends Application
{
#Override
public void onCreate()
{
super.onCreate();
//register your Broadcast receiver here
IntentFilter intentFilter = new IntentFilter("MANUAL_BROADCAST_RECIEVER");
registerReceiver(new BroadcastReciever(), intentFilter);
}
}
This is how I have done it, it is a modified version of the answer given by ceph3us and edited by slinden77 (among other things I have removed return values of methods which I did not need):
public class MyBroadcastReceiver extends BroadcastReceiver{
private boolean isRegistered;
public void register(final Context context) {
if (!isRegistered){
Log.d(this.toString(), " going to register this broadcast receiver");
context.registerReceiver(this, new IntentFilter("MY_ACTION"));
isRegistered = true;
}
}
public void unregister(final Context context) {
if (isRegistered) {
Log.d(this.toString(), " going to unregister this broadcast receiver");
context.unregisterReceiver(this);
isRegistered = false;
}
}
#Override
public void onReceive(final Context context, final Intent intent) {
switch (getResultCode()){
//DO STUFF
}
}
}
Then on an Activity class:
public class MyFragmentActivity extends SingleFragmentActivity{
MyBroadcastReceiver myBroadcastReceiver;
#Override
protected void onCreate(Bundle savedInstanceState){
super.onCreate(savedInstanceState);
registerBroacastReceiver();
}
#Override
protected Fragment createFragment(){
return new MyFragment();
}
//This method is called by the fragment which is started by this activity,
//when the Fragment is done, we also register the receiver here (if required)
#Override
public void receiveDataFromFragment(MyData data) {
registerBroacastReceiver();
//Do some stuff
}
#Override
protected void onStop(){
unregisterBroacastReceiver();
super.onStop();
}
void registerBroacastReceiver(){
if (myBroadcastReceiver == null)
myBroadcastReceiver = new MyBroadcastReceiver();
myBroadcastReceiver.register(this.getApplicationContext());
}
void unregisterReceiver(){
if (MyBroadcastReceiver != null)
myBroadcastReceiver.unregister(this.getApplicationContext());
}
}
For me the following worked:
if (receiver.isOrderedBroadcast()) {
requireContext().unregisterReceiver(receiver);
}
Here's what I did to check if the Broadcaster is already registered, even if you close you application (finish())
Firstime running your application, send a broadcast first it will return true/false depends on if your broadcaster in still running or not.
My Broadcaster
public class NotificationReceiver extends BroadcastReceiver {
#Override
public void onReceive(Context context, Intent intent) {
if(intent.getExtras() != null && intent.getStringExtra("test") != null){
Log.d("onReceive","test");
return;
}
}
}
My MainActivity
// init Broadcaster
private NotificationReceiver nr = new NotificationReceiver();
Intent msgrcv = new Intent("Msg");
msgrcv.putExtra("test", "testing");
boolean isRegistered = LocalBroadcastManager.getInstance(this).sendBroadcast(msgrcv);
if(!isRegistered){
Toast.makeText(this,"Starting Notification Receiver...",Toast.LENGTH_LONG).show();
LocalBroadcastManager.getInstance(this).registerReceiver(nr,new IntentFilter("Msg"));
}
if( receiver.isOrderedBroadcast() ){
// receiver object is registered
}
else{
// receiver object is not registered
}
Just check NullPointerException. If receiver does not exist, then...
try{
Intent i = new Intent();
i.setAction("ir.sss.smsREC");
context.sendBroadcast(i);
Log.i("...","broadcast sent");
}
catch (NullPointerException e)
{
e.getMessage();
}
I am creating an application in which I am sending SMS automatically on button click.When SMS is sent I get a response from server in form of SMS.I read that message and perform task on it. Now problem is that when I receive SMS I want to consider only messages received within one minute after button click. What to do.?
public class IncomingSms extends BroadcastReceiver {
#Override
public void onReceive(Context context, Intent intent)
{
Global mApplication = ((Global)context.getApplicationContext());
String getPPN=mApplication.getPPN();
String getStatus=mApplication.getvStatus();
String ClientId=mApplication.getvClientId();
String MobileNo=mApplication.getvStrMobile();
String LocationId=mApplication.getVstrLocation();
String IMEI=mApplication.getVstrIMEI();
final Bundle bundle = intent.getExtras();
try {
if (bundle != null)
{
final Object[] pdusObj = (Object[]) bundle.get("pdus");
for (int i = 0; i < pdusObj .length; i++)
{
SmsMessage currentMessage = SmsMessage.createFromPdu((byte[]) pdusObj[i]);
String phoneNumber = currentMessage.getDisplayOriginatingAddress();
String senderNum = phoneNumber ;
String message = currentMessage .getDisplayMessageBody();
mApplication.setvSenderNumber(senderNum);
mApplication.setvMessageBody(message);
String IsBroadCast=mApplication.getvAuthenticatedUser();
try
{
if(IsBroadCast=="1")
{
context.sendBroadcast(new Intent("Message_Recived"));
}
}
catch(Exception e){}
}
}
} catch (Exception e)
{
}
}
}
This class is called when SMS received and take me to Arming Activity's on receive method.
But I need that..Broadcast receiver only receive message only within 1 minute after sendinf SMS
ArmingActivity:
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_arming);
registerReceiver(broadcastReceiver, new IntentFilter("Message_Recived"));}
BroadcastReceiver broadcastReceiver = new BroadcastReceiver() {
#Override
public void onReceive(Context context, Intent intent) {
// internet lost alert dialog method call from here...
// if(strPPN.equals())
Global globalVariable = (Global) getApplicationContext();
String vvSenderNumber=globalVariable.getvSenderNumber();
String vvMessageBody=globalVariable.getvMessageBody();
String vvPPN=strPPN;
};
public void sendSms(String PPN, String smsBody) {
try {
SmsManager smsManager = SmsManager.getDefault();
smsManager.sendTextMessage(PPN, null, smsBody, null, null);
} catch (Exception e) {
e.printStackTrace();
}
}
if (strActionText.equals("1"))
{
sendSms(strPPN, MsgBody);
}
Here when send SMS start Broadcast receiver to start receiving SMS for 1 minute.
What to do?
you can do this with the Handler
for that start/register receiver and also start the Handler for the one minute
//start your broadcast here.
new Handler().postDelayed(new Runnable() {
#Override
public void run() {
// write code to stop/unregister receiver.
}
}, 60*1000);
for further display time you can use CountDownTimer class.
MainActivity.java
public class MainActivity extends Activity {
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.anaekran);
Thread t = new Thread(new Runnable() {
public void run() {
String smsMsj = getIntent().getStringExtra("sms");
if(smsMsj != null){
Toast.makeText(getApplication(), smsMsj, 2).show();
}
try {
Thread.sleep(4000);
} catch (InterruptedException e) {
e.printStackTrace();
}
}
});
t.start();
}
}
SmsReceiver.java
public class SmsReceiver extends BroadcastReceiver {
public void onReceive(Context context, Intent intent) {
Bundle mesaj = intent.getExtras();
SmsMessage[] smsMessage = null;
String msj = "";
if(mesaj!= null){
Object[] pdus = (Object[])mesaj.get("pdus");
smsMessage = new SmsMessage[pdus.length];
for(int i = 0; i < pdus.length; i++){
smsMessage[i] = SmsMessage.createFromPdu((byte[])pdus[i]);
msj = smsMessage[i].getMessageBody();
}
Intent mIntent = new Intent(context, SmsReceiver.class);
mIntent.putExtra("sms", msj);
}
}
}
My receiver working correctly but i have one problem when message coming i want to show on my MainAcitivty toast, so i create mIntent in receiver class, and then im use putExtra method.
But not working, sory for my bad english and thank you :)
Perhaps using explicit Intent and starting it could help you, hm? :)
Intent mIntent = new Intent(context, MainActivity.class);
mIntent.putExtra("sms", msj);
context.startActivity(mIntent);
Your mistake is that you construct your new Intent with SmsReceiver.class (but you need to launch MainActivity) and that you do not start any activity with such an intent.
Edit 1: Also, pay attention - you are trying to run a toast inside your worker thread. This is not possible. Remove your anonymous Thread and move your toast code to your onCreate(Bundle):
protected void onCreate(Bundle saveState){
....
String smsMsj = getIntent().getStringExtra("sms");
if(smsMsj != null){
Toast.makeText(getApplication(), smsMsj, 2).show();
}
....
}
Edit 2: Moreover, your duration parameter in Toast.makeText(..) is set to 2. This does not correspond to any magic constant in Toast class. You have to use one of the constants: Toast.LENGTH_LONG or Toast.LENGTH_SHORT. So, rewrite your code to:
Toast.makeText(getApplication(), smsMsj, Toast.LENGTH_SHORT);
I need to check if my registered receiver is still registered if not how do i check it any methods?
There is no API function to check if a receiver is registered. The workaround is to put your code in a try catch block as done below.
try {
//Register or UnRegister your broadcast receiver here
} catch(IllegalArgumentException e) {
e.printStackTrace();
}
I am not sure the API provides directly an API, if you consider this thread:
I was wondering the same thing.
In my case I have a BroadcastReceiver implementation that calls
Context#unregisterReceiver(BroadcastReceiver) passing itself as the argument after handling the Intent that it receives.
There is a small chance that the receiver's onReceive(Context, Intent) method is called
more than once, since it is registered with multiple IntentFilters, creating the potential for an IllegalArgumentException being thrown from Context#unregisterReceiver(BroadcastReceiver).
In my case, I can store a private synchronized member to check before calling Context#unregisterReceiver(BroadcastReceiver), but it would be
much cleaner if the API provided a check method.
simplest solution
in receiver:
public class MyReceiver extends BroadcastReceiver {
public boolean isRegistered;
/**
* register receiver
* #param context - Context
* #param filter - Intent Filter
* #return see Context.registerReceiver(BroadcastReceiver,IntentFilter)
*/
public Intent register(Context context, IntentFilter filter) {
try {
// ceph3us note:
// here I propose to create
// a isRegistered(Contex) method
// as you can register receiver on different context
// so you need to match against the same one :)
// example by storing a list of weak references
// see LoadedApk.class - receiver dispatcher
// its and ArrayMap there for example
return !isRegistered
? context.registerReceiver(this, filter)
: null;
} finally {
isRegistered = true;
}
}
/**
* unregister received
* #param context - context
* #return true if was registered else false
*/
public boolean unregister(Context context) {
// additional work match on context before unregister
// eg store weak ref in register then compare in unregister
// if match same instance
return isRegistered
&& unregisterInternal(context);
}
private boolean unregisterInternal(Context context) {
context.unregisterReceiver(this);
isRegistered = false;
return true;
}
// rest implementation here
// or make this an abstract class as template :)
...
}
in code:
MyReceiver myReceiver = new MyReceiver();
myReceiver.register(Context, IntentFilter); // register
myReceiver.unregister(Context); // unregister
ad 1
-- in reply to:
This really isn't that elegant because you have to remember to set the
isRegistered flag after you register. – Stealth Rabbi
-- "more ellegant way" added method in receiver to register and set flag
this won't work If you restart the device or if your app got killed by
OS. – amin 6 hours ago
#amin - see lifetime of in code (not system registered by manifest entry) registered receiver :)
I am using this solution
public class ReceiverManager {
private WeakReference<Context> cReference;
private static List<BroadcastReceiver> receivers = new ArrayList<BroadcastReceiver>();
private static ReceiverManager ref;
private ReceiverManager(Context context) {
cReference = new WeakReference<>(context);
}
public static synchronized ReceiverManager init(Context context) {
if (ref == null) ref = new ReceiverManager(context);
return ref;
}
public Intent registerReceiver(BroadcastReceiver receiver, IntentFilter intentFilter) {
receivers.add(receiver);
Intent intent = cReference.get().registerReceiver(receiver, intentFilter);
Log.i(getClass().getSimpleName(), "registered receiver: " + receiver + " with filter: " + intentFilter);
Log.i(getClass().getSimpleName(), "receiver Intent: " + intent);
return intent;
}
public boolean isReceiverRegistered(BroadcastReceiver receiver) {
boolean registered = receivers.contains(receiver);
Log.i(getClass().getSimpleName(), "is receiver " + receiver + " registered? " + registered);
return registered;
}
public void unregisterReceiver(BroadcastReceiver receiver) {
if (isReceiverRegistered(receiver)) {
receivers.remove(receiver);
cReference.get().unregisterReceiver(receiver);
Log.i(getClass().getSimpleName(), "unregistered receiver: " + receiver);
}
}
}
You have several options
You can put a flag into your class or activity. Put a boolean variable into your class and look at this flag to know if you have the Receiver registered.
Create a class that extends the Receiver and there you can use:
Singleton pattern for only have one instance of this class in your project.
Implement the methods for know if the Receiver is register.
You have to use try/catch:
try {
if (receiver!=null) {
Activity.this.unregisterReceiver(receiver);
}
} catch (IllegalArgumentException e) {
e.printStackTrace();
}
You can do it easy....
1) create a boolean variable ...
private boolean bolBroacastRegistred;
2) When you register your Broadcast Receiver, set it to TRUE
...
bolBroacastRegistred = true;
this.registerReceiver(mReceiver, new IntentFilter(BluetoothDevice.ACTION_FOUND));
....
3) In the onPause() do it...
if (bolBroacastRegistred) {
this.unregisterReceiver(mReceiver);
bolBroacastRegistred = false
}
Just it, and now, you will not receive more exception error message on onPause().
Tip1: Always use the unregisterReceiver() in onPause() not in onDestroy()
Tip2: Dont forget to set the bolBroadcastRegistred variable to FALSE when run the unregisterReceive()
Success!
If you put this on onDestroy or onStop method. I think that when the activity has been created again the MessageReciver wasn't being created.
#Override
public void onDestroy (){
super.onDestroy();
LocalBroadcastManager.getInstance(context).unregisterReceiver(mMessageReceiver);
}
Personally I use the method of calling unregisterReceiver and swallowing the exception if it's thrown. I agree this is ugly but the best method currently provided.
I've raised a feature request to get a boolean method to check if a receiver is registered added to the Android API. Please support it here if you want to see it added:
https://code.google.com/p/android/issues/detail?id=73718
I used Intent to let Broadcast Receiver know about Handler instance of main Activity thread and used Message to pass a message to Main activity
I have used such mechanism to check if Broadcast Receiver is already registered or not. Sometimes it is needed when you register your Broadcast Receiver dynamically and do not want to make it twice or you present to the user if Broadcast Receiver is running.
Main activity:
public class Example extends Activity {
private BroadCastReceiver_example br_exemple;
final Messenger mMessenger = new Messenger(new IncomingHandler());
private boolean running = false;
static class IncomingHandler extends Handler {
#Override
public void handleMessage(Message msg) {
running = false;
switch (msg.what) {
case BroadCastReceiver_example.ALIVE:
running = true;
....
break;
default:
super.handleMessage(msg);
}
}
}
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
IntentFilter filter = new IntentFilter();
filter.addAction("pl.example.CHECK_RECEIVER");
br_exemple = new BroadCastReceiver_example();
getApplicationContext().registerReceiver(br_exemple , filter); //register the Receiver
}
// call it whenever you want to check if Broadcast Receiver is running.
private void check_broadcastRunning() {
/**
* checkBroadcastHandler - the handler will start runnable which will check if Broadcast Receiver is running
*/
Handler checkBroadcastHandler = null;
/**
* checkBroadcastRunnable - the runnable which will check if Broadcast Receiver is running
*/
Runnable checkBroadcastRunnable = null;
Intent checkBroadCastState = new Intent();
checkBroadCastState .setAction("pl.example.CHECK_RECEIVER");
checkBroadCastState .putExtra("mainView", mMessenger);
this.sendBroadcast(checkBroadCastState );
Log.d(TAG,"check if broadcast is running");
checkBroadcastHandler = new Handler();
checkBroadcastRunnable = new Runnable(){
public void run(){
if (running == true) {
Log.d(TAG,"broadcast is running");
}
else {
Log.d(TAG,"broadcast is not running");
}
}
};
checkBroadcastHandler.postDelayed(checkBroadcastRunnable,100);
return;
}
.............
}
Broadcast Receiver:
public class BroadCastReceiver_example extends BroadcastReceiver {
public static final int ALIVE = 1;
#Override
public void onReceive(Context context, Intent intent) {
// TODO Auto-generated method stub
Bundle extras = intent.getExtras();
String action = intent.getAction();
if (action.equals("pl.example.CHECK_RECEIVER")) {
Log.d(TAG, "Received broadcast live checker");
Messenger mainAppMessanger = (Messenger) extras.get("mainView");
try {
mainAppMessanger.send(Message.obtain(null, ALIVE));
} catch (RemoteException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
.........
}
}
i put this code in my parent activity
List registeredReceivers = new ArrayList<>();
#Override
public Intent registerReceiver(BroadcastReceiver receiver, IntentFilter filter) {
registeredReceivers.add(System.identityHashCode(receiver));
return super.registerReceiver(receiver, filter);
}
#Override
public void unregisterReceiver(BroadcastReceiver receiver) {
if(registeredReceivers.contains(System.identityHashCode(receiver)))
super.unregisterReceiver(receiver);
}
I get your problem, I faced the same problem in my Application. I was calling registerReceiver() multiple time within the application.
A simple solution to this problem is to call the registerReceiver() in your Custom Application Class. This will ensure that your Broadcast receiver will be called only one in your entire Application lifecycle.
public class YourApplication extends Application
{
#Override
public void onCreate()
{
super.onCreate();
//register your Broadcast receiver here
IntentFilter intentFilter = new IntentFilter("MANUAL_BROADCAST_RECIEVER");
registerReceiver(new BroadcastReciever(), intentFilter);
}
}
This is how I have done it, it is a modified version of the answer given by ceph3us and edited by slinden77 (among other things I have removed return values of methods which I did not need):
public class MyBroadcastReceiver extends BroadcastReceiver{
private boolean isRegistered;
public void register(final Context context) {
if (!isRegistered){
Log.d(this.toString(), " going to register this broadcast receiver");
context.registerReceiver(this, new IntentFilter("MY_ACTION"));
isRegistered = true;
}
}
public void unregister(final Context context) {
if (isRegistered) {
Log.d(this.toString(), " going to unregister this broadcast receiver");
context.unregisterReceiver(this);
isRegistered = false;
}
}
#Override
public void onReceive(final Context context, final Intent intent) {
switch (getResultCode()){
//DO STUFF
}
}
}
Then on an Activity class:
public class MyFragmentActivity extends SingleFragmentActivity{
MyBroadcastReceiver myBroadcastReceiver;
#Override
protected void onCreate(Bundle savedInstanceState){
super.onCreate(savedInstanceState);
registerBroacastReceiver();
}
#Override
protected Fragment createFragment(){
return new MyFragment();
}
//This method is called by the fragment which is started by this activity,
//when the Fragment is done, we also register the receiver here (if required)
#Override
public void receiveDataFromFragment(MyData data) {
registerBroacastReceiver();
//Do some stuff
}
#Override
protected void onStop(){
unregisterBroacastReceiver();
super.onStop();
}
void registerBroacastReceiver(){
if (myBroadcastReceiver == null)
myBroadcastReceiver = new MyBroadcastReceiver();
myBroadcastReceiver.register(this.getApplicationContext());
}
void unregisterReceiver(){
if (MyBroadcastReceiver != null)
myBroadcastReceiver.unregister(this.getApplicationContext());
}
}
For me the following worked:
if (receiver.isOrderedBroadcast()) {
requireContext().unregisterReceiver(receiver);
}
Here's what I did to check if the Broadcaster is already registered, even if you close you application (finish())
Firstime running your application, send a broadcast first it will return true/false depends on if your broadcaster in still running or not.
My Broadcaster
public class NotificationReceiver extends BroadcastReceiver {
#Override
public void onReceive(Context context, Intent intent) {
if(intent.getExtras() != null && intent.getStringExtra("test") != null){
Log.d("onReceive","test");
return;
}
}
}
My MainActivity
// init Broadcaster
private NotificationReceiver nr = new NotificationReceiver();
Intent msgrcv = new Intent("Msg");
msgrcv.putExtra("test", "testing");
boolean isRegistered = LocalBroadcastManager.getInstance(this).sendBroadcast(msgrcv);
if(!isRegistered){
Toast.makeText(this,"Starting Notification Receiver...",Toast.LENGTH_LONG).show();
LocalBroadcastManager.getInstance(this).registerReceiver(nr,new IntentFilter("Msg"));
}
if( receiver.isOrderedBroadcast() ){
// receiver object is registered
}
else{
// receiver object is not registered
}
Just check NullPointerException. If receiver does not exist, then...
try{
Intent i = new Intent();
i.setAction("ir.sss.smsREC");
context.sendBroadcast(i);
Log.i("...","broadcast sent");
}
catch (NullPointerException e)
{
e.getMessage();
}