telephony - How to hang up outgoing call in Android?

Question

I am developing an application where one of the things we need is to control the outgoing call, at least to be able to stop it from our application.

I've tried using Intent.ACTION_CALL from an existing activity:

Intent callIntent = new Intent(Intent.ACTION_CALL, Uri.parse("tel:" + phoneNumber)); 
startActivity(callIntent); 

But stopping the call seems to be disallowed through the API.

Can you suggest some workaround?

For example: enabling airplane mode during the call? Just an example; this hack didn't work for me.

Answer 1

Capturing the outgoing call in a BroadcastReceiver has been mentioned and is definitely the best way to do it if you want to end the call before dialing.

Once dialing or in-call, however, that technique no longer works. The only way to hang up that I've encountered so far, is to do so through Java Reflection. As it is not part of the public API, you should be careful to use it, and not rely upon it. Any change to the internal composition of Android will effectively break your application.

Prasanta Paul's blog demonstrates how it can be accomplished, which I have summarized below.

Obtaining the ITelephony object:

TelephonyManager tm = (TelephonyManager) context
        .getSystemService(Context.TELEPHONY_SERVICE);
try {
    // Java reflection to gain access to TelephonyManager's
    // ITelephony getter
    Log.v(TAG, "Get getTeleService...");
    Class c = Class.forName(tm.getClass().getName());
    Method m = c.getDeclaredMethod("getITelephony");
    m.setAccessible(true);
    com.android.internal.telephony.ITelephony telephonyService =
            (ITelephony) m.invoke(tm);
} catch (Exception e) {
    e.printStackTrace();
    Log.e(TAG,
            "FATAL ERROR: could not connect to telephony subsystem");
    Log.e(TAG, "Exception object: " + e);
}

Ending the call:

telephonyService.endCall();