Android, TelephonyManager, the joys of PhoneStateListener and incoming numbers

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Android

telephony

I've very newly gotten into Android development, and decided that my first conquest on this fresh field would be to grasp how the phone reacted to incoming calls.

A little googling later led me to http://www.compiletimeerror.com/2013/08/android-call-state-listener-example.html#.Vi3Ren4vfwM (so my code shares a striking resemblance to his/hers).

My main (and only) activity looks like this:

package com.example.x.telephonymanagertest;

import android.content.Context;
import android.os.Bundle;
import android.support.v7.app.AppCompatActivity;
import android.telephony.PhoneStateListener;
import android.telephony.TelephonyManager;
import android.util.Log;
import android.view.Menu;
import android.widget.Toast;

public class MainActivity extends AppCompatActivity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        TelephonyManager TelephonyMgr = (TelephonyManager) getSystemService(Context.TELEPHONY_SERVICE);
        TelephonyMgr.listen(new TeleListener(), PhoneStateListener.LISTEN_CALL_STATE);
    }

    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        getMenuInflater().inflate(R.menu.activity_main, menu);
        return true;
    }

    class TeleListener extends PhoneStateListener {

        @Override
        public void onCallStateChanged(int state, String incomingNumber) {
            super.onCallStateChanged(state, incomingNumber);
            switch (state) {
                case TelephonyManager.CALL_STATE_IDLE:
                    // CALL_STATE_IDLE;
                    Log.i("WORDS", " I NEED TO HEAR  :" + incomingNumber);
                    Toast.makeText(getApplicationContext(), "CALL_STATE_IDLE",
                            Toast.LENGTH_LONG).show();
                    break;
                case TelephonyManager.CALL_STATE_OFFHOOK:
                    // CALL_STATE_OFFHOOK;
                    Log.i("WORDS", " I NEED TO HEAR  :" + incomingNumber);

                    Toast.makeText(getApplicationContext(), "CALL_STATE_OFFHOOK",
                            Toast.LENGTH_LONG).show();
                    break;
                case TelephonyManager.CALL_STATE_RINGING:
                    // CALL_STATE_RINGING
                    Log.i("WORDS", " I NEED TO HEAR  :" + incomingNumber);
                    Toast.makeText(getApplicationContext(), incomingNumber,
                            Toast.LENGTH_LONG).show();
                    Toast.makeText(getApplicationContext(), "CALL_STATE_RINGING",
                            Toast.LENGTH_LONG).show();
                    break;
                default:
                    break;
            }
        }

    }
}

Now, here's where the fun stops. I got the app running on emulator, and used DDMS to spoof a few phone calls to my emulated device to see where the pieces landed.

And surely enough toast popped up and MyLittleDebugger flared up upon state swaps. The listener was working, however no number was ever being shown in my log or my toast.

It was just blank where the number should have been! Not null or anything, no, but blank!

After a little more googling, I realized that my AndroidManifest.xml might be the problem. It is as follows:

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

    <uses-permission android:name="android.permission.READ_PHONE_STATE" />

    <application
        android:allowBackup="true"
        android:icon="@mipmap/ic_launcher"
        android:label="@string/app_name"
        android:supportsRtl="true"
        android:theme="@style/AppTheme" >
        <activity android:name=".MainActivity" >
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />

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

</manifest>

Now, here's the question: what am I missing?

Clearly, a little fraction of a something has gone wrong somewhere, because I am able to have my TelephonyMgr object .listen() to call states, but I can't get the number to show.