Tigger alertBox from c2dm listener events
<p>I want to add progress and alert dialogs to whatever the active context may be, whenever the listener receives a message. With this code:</p>

<pre><code>public class C2DMMessageReceiver extends BroadcastReceiver {
        @Override
                public void onReceive(Context context, Intent intent) {
                    String action = intent.getAction();
                    Log.w("C2DM", "Message Receiver called");
                    if ("com.google.android.c2dm.intent.RECEIVE".equals(action)) {
                        Log.w("C2DM", "Received message");
                        final String payload = intent.getStringExtra("payload");
                        Log.d("C2DM", "dmControl: payload = " + payload);

                        // Message handling
                        if(payload.equals("DataUpdate")) {
                            progressDialog = ProgressDialog.show(context, "Please wait...", "Synchronizing data ...", true);
                syncData(context);
                progressDialog.dismiss();
                AlertDialog.Builder alertbox = new AlertDialog.Builder(context);
                alertbox.setMessage("Data was updated");
                alertbox.create();
                alertbox.show();
                        }
                    }
                }
    }
</code></pre>

<p>I get the following error when i recieve message:</p>

<pre><code>01-07 08:44:38.190: E/AndroidRuntime(750): Caused by: android.view.WindowManager$BadTokenException: Unable to add window -- token null is not for an application
</code></pre>

<p>Trying to figure out what the best way to handle this would be, do I need to cache the active context in a singleton, and then access said singleton from the listener? Or is there a better way? </p>

<p>Thanks</p>
