Logo Questions Linux Laravel Mysql Ubuntu Git Menu
 

How to use getApplicationContext in BroadcastReceiver class?

I am using the broadcaster class to listen to sms messages using this code

package com.escortme.basic;

import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.Intent;
import android.os.Bundle;
import android.telephony.SmsMessage;
import android.widget.Toast;

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";
                //}
            }
            // Display the SMS as Toast.
            Toast.makeText(context, str, Toast.LENGTH_SHORT).show();


            Pol_ViewActivity appState = ((Pol_ViewActivity)getApplicationContext()); // ERROR
            appState.move_map_to("33.786047","-59.187287");
        }
    }
}

and it's defined in manifest like so

    <receiver 
      android:name="com.escortme.basic.SMSReceiverActivity"
      android:enabled="true">
      <intent-filter>
        <action android:name="android.provider.Telephony.SMS_RECEIVED" />
      </intent-filter>
    </receiver>

But the problem is it says "The method getApplicationContext() is undefined for the type SMSReceiverActivity".

Does anyone know why this is happening and how to fix it? Thanks

like image 864
omega Avatar asked Jul 03 '12 01:07

omega


People also ask

When would you call getApplicationContext () and why?

This method is generally used for the application level and can be used to refer to all the activities. For example, if we want to access a variable throughout the android app, one has to use it via getApplicationContext().

What is the role of the onReceive () method in the BroadcastReceiver?

Retrieve the current result extra data, as set by the previous receiver. This can be called by an application in onReceive(Context, Intent) to allow it to keep the broadcast active after returning from that function.

Which of the following method is used to add a broadcast receiver?

We have added broadcastIntent() method to broadcast a custom intent. You can try implementing other BroadcastReceiver to intercept system generated intents like system boot up, date changed, low battery etc.

How pass data from BroadcastReceiver to activity in Android?

Step 1. Open your project where you want to implement this. Step 2. Open your BroadcastReceiver class from where you pass data to activity inside your onReceive() you need to start intent and pass data inside intent and start sendBroadcast() as shown bellow.


3 Answers

One reason for getting the application context would be to get the the WIFI_SERVICE as it must be looked up on the Application context or memory will leak on devices < Android N.

As Someone Somewhere once said, within onReceive(), just use context.getApplicationContext().

like image 132
jpihl Avatar answered Oct 19 '22 17:10

jpihl


Look at the method signature for onReceive()

public void onReceive(Context context, Intent intent) {

You are being passed a context as a parameter. You should be using that context when you need one.

Pol_ViewActivity appState = ((Pol_ViewActivity)context); 

EDIT: also I don't know exactly what it is you are trying to do. But you probably shouldn't be trying to obtain an Activity object and call a method on it like you seem to be doing.

like image 40
FoamyGuy Avatar answered Oct 19 '22 18:10

FoamyGuy


I hope this may help you my frnd.

Try importing this package (import android.telephony.gsm.SmsManager;)

//---sends a SMS message to another device--- private void sendSMS(String phoneNumber, String message) {
String SENT = "SMS_SENT"; String DELIVERED = "SMS_DELIVERED";

    PendingIntent sentPI = PendingIntent.getBroadcast(this, 0,
        new Intent(SENT), 0);

    PendingIntent deliveredPI = PendingIntent.getBroadcast(this, 0,
        new Intent(DELIVERED), 0);

    //---when the SMS has been sent---
    registerReceiver(new BroadcastReceiver(){
        @Override
        public void onReceive(Context arg0, Intent arg1) {
            switch (getResultCode())
            {
                case Activity.RESULT_OK:
                    Toast.makeText(getBaseContext(), "SMS sent", 
                            Toast.LENGTH_SHORT).show();
                    break;
                case SmsManager.RESULT_ERROR_GENERIC_FAILURE:
                    Toast.makeText(getBaseContext(), "Generic failure", 
                            Toast.LENGTH_SHORT).show();
                    break;
                case SmsManager.RESULT_ERROR_NO_SERVICE:
                    Toast.makeText(getBaseContext(), "No service", 
                            Toast.LENGTH_SHORT).show();
                    break;
                case SmsManager.RESULT_ERROR_NULL_PDU:
                    Toast.makeText(getBaseContext(), "Null PDU", 
                            Toast.LENGTH_SHORT).show();
                    break;
                case SmsManager.RESULT_ERROR_RADIO_OFF:
                    Toast.makeText(getBaseContext(), "Radio off", 
                            Toast.LENGTH_SHORT).show();
                    break;
            }
        }
    }, new IntentFilter(SENT));

    //---when the SMS has been delivered---
    registerReceiver(new BroadcastReceiver(){
        @Override
        public void onReceive(Context arg0, Intent arg1) {
            switch (getResultCode())
            {
                case Activity.RESULT_OK:
                    Toast.makeText(getBaseContext(), "SMS delivered", 
                            Toast.LENGTH_SHORT).show();
                    break;
                case Activity.RESULT_CANCELED:
                    Toast.makeText(getBaseContext(), "SMS not delivered", 
                            Toast.LENGTH_SHORT).show();
                    break;                      
            }
        }
    }, new IntentFilter(DELIVERED));        

    SmsManager sms = SmsManager.getDefault();
    sms.sendTextMessage(phoneNumber, null, message, sentPI, deliveredPI);               
}    
like image 22
sathish Avatar answered Oct 19 '22 19:10

sathish