AlertDialog from within BroadcastReceiver?? Can it be done?

Question

AlertDialog from within BroadcastReceiver? Can it be done? I am working on a app that will pop up a Dialog box if I get SMS message. I am trying to code this within a BroadcaseReceiver. But I cant use this line of code AlertDialog.Builder builder = new AlertDialog.Builder(this);. Can someone please help me with a hint!

public class SMSPopUpReceiver extends BroadcastReceiver {

    private static final String LOG_TAG = "SMSReceiver";
    public static final int NOTIFICATION_ID_RECEIVED = 0x1221;
    static final String ACTION = "android.provider.Telephony.SMS_RECEIVED";

    public void onReceive(Context context, Intent intent) {
        Log.i(LOG_TAG, "onReceive");

        if (intent.getAction().equals(SMSPopUpReceiver.ACTION)) {
            StringBuilder sb = new StringBuilder();
            Bundle bundle = intent.getExtras();
            if (bundle != null) {
            Object[] pdus = (Object[]) bundle.get("pdus");

            for (Object pdu : pdus){
                    SmsMessage messages =
            SmsMessage.createFromPdu((byte[]) pdu);

            sb.append("Received SMS\nFrom: ");
            sb.append(messages.getDisplayOriginatingAddress());
            sb.append("\n----Message----\n");
            sb.append( messages.getDisplayMessageBody());
            }
            }
            Log.i(SMSPopUpReceiver.LOG_TAG,
            "[SMSApp] onReceiveIntent: " + sb);
            Toast.makeText
            (context, sb.toString(), Toast.LENGTH_LONG).show();
            }

        AlertDialog.Builder builder = new AlertDialog.Builder(this);
        builder.setMessage("Are you sure you want to exit?")
               .setCancelable(false)
               .setPositiveButton("Yes", new DialogInterface.OnClickListener() {
                   public void onClick(DialogInterface dialog, int id) {
                       dialog.cancel();
                   }
               })
               .setNegativeButton("No", new DialogInterface.OnClickListener() {
                   public void onClick(DialogInterface dialog, int id) {
                        dialog.cancel();
                   }
               });
        AlertDialog alert = builder.create();
    }

}

Answer 1

Principal issue: try to avoid placing time consuming functionalities into BroadcastReceiver. It should just receive and initiate further processing in bound Activity/Service.

UPDATE:

Please check following sources that might be helpful:

Similar questions on StackOverflow:

How to send data from BroadcastReceiver to an Activity in android?

Android SMS receiver not working

Android SDK demo example:

android-sdk-windows\samples\android-8\ApiDemos\src\com\example\android\apis\os\SmsMessagingDemo.java

And of course standard Android API documentation: http://developer.android.com/reference/android/content/BroadcastReceiver.html

UPDATE2:

Added app skeleton as it should look. Please note that no content view is defined. It is because your app will have transparent screen. To achieve that

@android:style/Theme.Translucent

is entered under Theme tag for this activity in AndroidManifest.xml.

public class NotifySMSReceived extends Activity 
{
    private static final String LOG_TAG = "SMSReceiver";
    public static final int NOTIFICATION_ID_RECEIVED = 0x1221;
    static final String ACTION = "android.provider.Telephony.SMS_RECEIVED";

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);

        IntentFilter filter = new IntentFilter(ACTION);
        this.registerReceiver(mReceivedSMSReceiver, filter);
    }

    private void displayAlert()
    {
        AlertDialog.Builder builder = new AlertDialog.Builder(this);
        builder.setMessage("Are you sure you want to exit?").setCancelable(
                false).setPositiveButton("Yes",
                new DialogInterface.OnClickListener() {
                    public void onClick(DialogInterface dialog, int id) {
                        dialog.cancel();
                    }
                }).setNegativeButton("No",
                new DialogInterface.OnClickListener() {
                    public void onClick(DialogInterface dialog, int id) {
                        dialog.cancel();
                    }
                });
        AlertDialog alert = builder.create();
        alert.show();
    }

    private final BroadcastReceiver mReceivedSMSReceiver = new BroadcastReceiver() {
        @Override
        public void onReceive(Context context, Intent intent) {
            String action = intent.getAction();

            if (ACTION.equals(action)) 
            {
                //your SMS processing code
                displayAlert();
            }
        }
    };    
}

Answer 2

I've been looking into it and the documentation of the BroadcastReceiver actually says:

public abstract void onReceive (Context context, Intent intent)

Since: API Level 1 This method is called when the BroadcastReceiver is receiving an Intent broadcast. During this time you can use the other methods on BroadcastReceiver to view/modify the current result values. The function is normally called within the main thread of its process, so you should never perform long-running operations in it (there is a timeout of 10 seconds that the system allows before considering the receiver to be blocked and a candidate to be killed). You cannot launch a popup dialog in your implementation of onReceive().

You cannot launch a popup dialog in your implementation of onReceive()

So it seems it is not possible

Answer 3

This is late but this may help someone.

You cannot use alert dialog inside broadcast receiver, we can use this only in activity or service. Try like this

In your onReceive method of broadcastreceiver add

Intent i = new Intent(context, yourclass.class);
                i.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
                context.startActivity(i);

and in yourclass set your dialog message, so that it will appear when you trigger the receiver event. I tried this and it worked me. Hope this may help some one :-)

Answer 4

you can create a new transparent activity and then create Alert Dialog in that activity, whenever your alert is to be displayed call that activity from your broadcast reciever ,this could work, not tested

Answer 5

replace the word "this" inside the AlertDilaog with "context" -- the first parameter on you onRecieve method.

 public void onReceive(Context context, Intent intent)