how to access com.android.internal.telephony.CallManager?

Question

I am trying to access CallManager class object from com.android.internal.telephony package.

Here is my code:

ClassLoader classLoader = TestActivity.class.getClassLoader();
final ClassLoader classLoader = this.getClass().getClassLoader();
try {
    final Class<?> classCallManager =
        classLoader.loadClass("com.android.internal.telephony.CallManager");
    Log.i("TestActivity", classCallManager);
} catch (final ClassNotFoundException e) {
    Log.e("TestActivity", e);
}

Unfortunately, this is throwing a ClassNotFoundException. The same approach allows me to access PhoneFactory, but apparently I'm not allowed to access CallManager.

If I could reach the class, then I'd want to proceed using the class as follows:

Method method_getInstance;
method_getInstance = classCallManager.getDeclaredMethod("getInstance");
method_getInstance.setAccessible(true);
Object callManagerInstance = method_getInstance.invoke(null);

Can anyone help me on this?

Thanks in advance,
Harsha C

Answer 1

I could successfully load CallManager and its methods. However, when I invoke getState(), getActiveFgCallState(), it always return IDLE even when the app receives different call states from TelephonyManager, i.e. TelephonyManager.CALL_STATE_IDLE, TelephonyManager.CALL_STATE_OFFHOOK, TelephonyManager.CALL_STATE_RINGING.

I used the following code to load the class and its methods:

final Class<?> classCallManager = classLoader.loadClass("com.android.internal.telephony.CallManager");
Log.i(TAG, "Class loaded " + classCallManager.toString());

Method methodGetInstance = classCallManager.getDeclaredMethod("getInstance");
Log.i(TAG, "Method loaded " + methodGetInstance.getName());

Object objectCallManager = methodGetInstance.invoke(null);
Log.i(TAG, "Object loaded " + objectCallManager.getClass().getName());


Method methodGetState = classCallManager.getDeclaredMethod("getState");
Log.i(TAG, "Method loaded " + methodGetState.getName());

Log.i(TAG, "Phone state = " + methodGetState.invoke(objectCallManager));

Btw, what I am trying to do is detecting when the phone starts ringing. I saw in the source code that ALERTING is the internal event that I should listen to. Therefore, I tried to use CallManager to get Call.State, rather than Phone.State. I also tried to use registerForPreciseCallStateChanges() of CallManager class but none of approached worked so far.