Why intent sent by LocalBroadCastManager from IntentService is not received by BroadCastReceiver within Activity class?

Question

ChooseLanguageFragment.java

Intent explicitGetNumberServiceIntentUSA = new Intent(getActivity(), GetNumberService.class);
explicitGetNumberServiceIntentUSA.putExtra("country", "USA");
getActivity().startService(explicitGetNumberServiceIntentUSA);

This is how the GetNumberService is called.

This is how the arraylist is passed from GetNumberService.java

Intent mobileNumbersIntent = new Intent();
mobileNumbersIntent.putStringArrayListExtra("mobileNumbers", mobileNumberList);
mobileNumbersIntent.setAction(ChooseNumber1.MobileNumberBroadcastReceiver.MOBILE_NO_RECEIVER);
mobileNumbersIntent.addCategory(Intent.CATEGORY_DEFAULT);
mobileNumbersIntent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK); //this is needed when callling startActivity() outisde an Activity            
sendBroadcast(mobileNumbersIntent);

in onHandleIntent() method.

GetNumberService does its job perfectly.

ChooseNumber1.java

public class ChooseNumber1 extends AppCompatActivity {
    private MobileNumberBroadcastReceiver receiver;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        IntentFilter intentFilter = new IntentFilter(MobileNumberBroadcastReceiver.MOBILE_NO_RECEIVER);
        intentFilter.addCategory(Intent.CATEGORY_DEFAULT);
        receiver = new MobileNumberBroadcastReceiver();
        registerReceiver(receiver, intentFilter);
        setContentView(R.layout.activity_choose_number1);
        Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
        setSupportActionBar(toolbar);
        getSupportActionBar().setDisplayHomeAsUpEnabled(true);
    }

    @Override
    protected void onDestroy(){
        unregisterReceiver(receiver);
        super.onDestroy();
    }

    public class MobileNumberBroadcastReceiver extends BroadcastReceiver {

        public static final String MOBILE_NO_RECEIVER = "abcd";
        ArrayList<String> mobileNumbersList = new ArrayList<>();
        ListView mobileNumberListView;
        ArrayAdapter<String> mobileNumberAdapter;

        @Override
        public void onReceive(Context context, Intent intent) {
          //  if(intent.getAction().equals(GetNumberService.MOBILE_NUMBER_LIST_PASS_ACTION)){
                mobileNumbersList = intent.getStringArrayListExtra("mobileNumberList");
         //   }
            mobileNumberAdapter = new ArrayAdapter<String>(new ChooseNumbers(),
                    R.layout.list_item_numbers, R.id.list_item_number_textview, mobileNumbersList);

            mobileNumberListView = (ListView) findViewById(R.id.listViewNumberList);
            mobileNumberListView.setAdapter(mobileNumberAdapter);
        }
    }

}

activity_choose_number1.xml

<?xml version="1.0" encoding="utf-8"?>
<android.support.design.widget.CoordinatorLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:fitsSystemWindows="true"
    tools:context="com.a2ndnumber.a2ndnumber.ChooseNumbers">

    <android.support.design.widget.AppBarLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:theme="@style/AppTheme.AppBarOverlay">

        <android.support.v7.widget.Toolbar
            android:id="@+id/toolbar"
            android:layout_width="match_parent"
            android:layout_height="?attr/actionBarSize"
            android:background="?attr/colorPrimary"
            app:popupTheme="@style/AppTheme.PopupOverlay" />

    </android.support.design.widget.AppBarLayout>

    <include layout="@layout/content_choose_number1" />

</android.support.design.widget.CoordinatorLayout>

content_choose_number1.xml

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:paddingBottom="@dimen/activity_vertical_margin"
    android:paddingLeft="@dimen/activity_horizontal_margin"
    android:paddingRight="@dimen/activity_horizontal_margin"
    android:paddingTop="@dimen/activity_vertical_margin"
    app:layout_behavior="@string/appbar_scrolling_view_behavior"
    tools:context="com.a2ndnumber.a2ndnumber.ChooseNumber1"
    tools:showIn="@layout/activity_choose_number1">

    <ListView
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:id="@+id/listViewNumberList"/>

</RelativeLayout>

PS 2:

Problem is, I am not able to receive the mobileNumbersIntent in ChooseNumber1.java or ChooseNumbersFragment.java. I think the issue is with BroadcastManager.java. If I debug, it goes to Handler.java and few other classes and finally mId=-1 and no error in stack trace. I am struck

PS: AndroidManifest.xml

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.a2ndnumber.a2ndnumber">

    <!-- TODO : Add permissions -->
    <uses-permission android:name="android.permission.INTERNET" />

    <!-- Contacts -->
    <application
        android:allowBackup="true"
        android:icon="@mipmap/ic_launcher"
        android:label="@string/app_name"
        android:supportsRtl="true"
        android:theme="@style/AppTheme">
        <activity
            android:name=".ChooseLanguage"
            android:label="@string/app_name"
            android:theme="@style/AppTheme.NoActionBar">
        </activity>
        <activity
            android:name=".Choose_Country"
            android:label="@string/app_name"
            android:parentActivityName=".ChooseLanguage"
            android:theme="@style/AppTheme.NoActionBar">
            <meta-data
                android:name="android.support.PARENT_ACTIVITY"
                android:value="com.a2ndnumber.a2ndnumber.ChooseLanguage" />
        </activity>
        <activity
            android:name=".MainActivity"
            android:noHistory="true">
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />

                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>

        <service android:name=".service.GetNumberService" />

        <activity
            android:name=".ChooseNumber1"
            android:label="@string/title_activity_choose_number1"
            android:parentActivityName=".Choose_Country"
            android:theme="@style/AppTheme.NoActionBar">
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />
                <category android:name="android.intent.category.DEFAULT" />
            </intent-filter>
            <meta-data
                android:name="android.support.PARENT_ACTIVITY"
                android:value="com.a2ndnumber.a2ndnumber.Choose_Country" />
        </activity>
    </application>

</manifest>

PS: I have modified my code a lot after going through tons of examples and answers in Stackoverflow. This is my latest code. Look like the issue is with intent-filter and/or getting intent using action. Please help me. Thanks.

Answer 1

The desired flow doesn't require a broadcast and Receiver setup. Since the ChooseNumber1 Activity is to be started after the Service has completed its work, you simply need to attach the ArrayList to the Intent used to start ChooseNumber1. The list can then be retrieved in onCreate(), and your ListView and its Adapter can be immediately initialized, rather than trying to wait for a broadcast.

For example, in your Service, after the list has been assembled:

Intent mobileNumbersIntent = new Intent(this, ChooseNumber1.class);
mobileNumbersIntent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
mobileNumbersIntent.putStringArrayListExtra("mobileNumbers", mobileNumberList);
startActivity(mobileNumbersIntent);

Then, in the Activity:

public class ChooseNumber1 extends AppCompatActivity {

    private ArrayAdapter<String> mobileNumberAdapter;
    private ArrayList<String> mobileNumbersList = new ArrayList<>();
    private ListView mobileNumberListView;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_choose_number1);

        ...

        mobileNumberListView = (ListView) findViewById(R.id.listViewNumberList);

        mobileNumbersList = getIntent().getStringArrayListExtra("mobileNumbers");
        if(mobileNumbersList != null) {
            mobileNumberAdapter = new ArrayAdapter<String>(this,
                                                           R.layout.list_item_numbers,
                                                           R.id.list_item_number_textview,
                                                           mobileNumbersList);
            mobileNumberListView.setAdapter(mobileNumberAdapter);
        }
    }
}

Answer 2

Your findViewById() is just fine and returns a non-null.

The problem is with the adapter as seen in the stacktrace: The mobileNumbersList list you're passing to it is null at the time when the adapter is assigned. ArrayAdapter needs a non-null array.

(There are a number of other problems with the code - this is just the NPE.)

Answer 3

I would suggest to inspect whether works this simple code:

inside Activity:

@Override
      protected void onResume() {
        super.onResume();
        IntentFilter intFilt = new IntentFilter(MYBROADCASTINGSTRING);
        registerReceiver(updbr,intFilt);
      }
    @Override
      protected void onPause() {
        super.onPause();
        unregisterReceiver(updbr);
      }


        private BroadcastReceiver updbr = new BroadcastReceiver() {
                @Override
                public void onReceive(Context context, Intent intent2) {
                    try {
Log.d("MYLOG", "gotcha!");
                    } catch (Exception e) {

                    }
                }
            };

Cast broadbast in the service while catching:

Intent intentBR = new Intent(MYBROADCASTINGSTRING);
        intentBR.putExtra(somestring, "teststring");
        sendBroadcast(intentBR);

Where the MYBROADCASTINGSTRING is some constant. E.g. public final static String MYBROADCASTINGSTRING = "MYBROADCASTINGSTRING"; It doesn't not need to improve AndroidManifest.xml. Does it work?

Answer 4

When you are sending the broadcast you are passing an extra like this

mobileNumbersIntent.putStringArrayListExtra("mobileNumbers", mobileNumberList);

And when you are reading that extra in the BroadcastReceiver, you're doing this.

mobileNumbersList = intent.getStringArrayListExtra("mobileNumberList");

You should be using the same key for extras. I would recommend using a constant in IntentService for this purpose.

public static final string EXTRA_MOBILE_NUMBERS = "mobile_numbers";

Then you could do stuff like:

mobileNumbersIntent.putStringArrayListExtra(MyIntentService.EXTRA_MOBILE_NUMBERS, mobileNumberList);

and

mobileNumbersList = intent.getStringArrayListExtra(MyIntentService.EXTRA_MOBILE_NUMBERS);

Answer 5

For handling result from IntentService, Use ResultReciver instead of the broadcast receiver.

Like this,

Step 1: Create the result handler using ResultReceiver inside activity

public ResultReceiver downloadReceiver = new ResultReceiver(new Handler()) {
    @Override
    protected void onReceiveResult(int resultCode, Bundle resultData) {
        super.onReceiveResult(resultCode, resultData);
        //Broadcast /send the result code in intent service based on your logic(success/error) handle with switch
        switch (resultCode) {
            case 1: {
                //Get the resultData and do your logic here
                //Update your list view item here
                break;
            }
            case 2: {
                //Get the resultData and do your logic here
                //Update your list view item here
                break;
            }
        }
    }
}; 

Step 2: Put the result handler inside the intent and start the intent service

Intent intent = new Intent(getContext(), DownloadService.class);
intent.putExtra("receiver",downloadReceiver);

Step 3: Handle the intent in service class(get the value of result handler)

final ResultReceiver receiver;

@Override
protected void onHandleIntent(Intent intent) {
    receiver = intent.getParcelableExtra("receiver");
}

Step 4: Send/Broadcast the data to the result handler

//based on your logic, change the result code and data

//Add your result data (success scenario)
Bundle bundle = new Bundle();
bundle.putString("result","Some text");
receiver.send(1,bundle);

//Add your result data (failure scenario)
receiver.send(0,bundle);